Tagged Vaccination and Immunization

Weekly Health Quiz: Exercise, Body Temperature and a Covid Vaccine Mystery

1 of 7

An 11-minute program of calisthenics and rest, done three times a week for six weeeks, had this effect on out-of-shape young men and women:

It increased their fitness levels

It improved their endurance by 7 percent

It increased their leg power slightly

All of the above

2 of 7

Which statement about body temperatures is not true?

Worldwide, average body temperatures seem to be decreasing

Body temperatures tend to rise during and after exercise

Older people tend to have lower body temperatures than younger people

Body temperature tends to be higher in the morning than in the evening

3 of 7

Health authorities are investigating the death of a 56-year-old doctor in Florida who developed this blood clotting disorder days after receiving the Covid vaccine:

Hemophilia

Pernicious anemia

Acute immune thrombocytopenia

Myelodysplastic syndrome

4 of 7

Creutzfeldt-Jakob disease, sometimes called mad cow disease, is thought to be caused by this type of infectious organism:

Bacteria

Virus

Fungus

Prion

5 of 7

Which statement about throat cancers is not true?

Most throat cancers are caused by human papillomavirus, or HPV

Having oral sex at a young age increases the risk of developing throat cancer

HPV-associated throat cancers are more common in women than men

HPV-associated throat cancers are more common in whites than in African-Americans

6 of 7

Being overweight during pregnancy was tied to this fertility issue, Danish researchers report:

Mothers who are overweight during their first pregnancy are at increased risk of fertility problems during subsequent pregnancies

Daughters born to overweight mothers were at increased risk of having fertility problems

Sons born to overweight mothers were at increased risk of being infertile

All of the above

7 of 7

Diets rich in this vitamin were tied to a lower risk of developing Parkinson’s disease:

Vitamin A

B vitamins

Vitamins C and E

Vitamin D

An Appreciation for Vaccines, and How Far They Have Come

The Checkup

An Appreciation for Vaccines, and How Far They Have Come

The DTP vaccine teaches us about how brilliant vaccine technology can be, but also how it can be studied and improved over time.

Credit…Getty Images

  • Jan. 11, 2021, 5:00 a.m. ET

This time of year, my thoughts turn to the DTP vaccine. Last year I wrote about the apocryphal “Christmas miracle” of 1891, in which the newly discovered diphtheria antitoxin may (or more likely, may not) have been used before it had been approved to save a child’s life.

Still, the moral was that bacteriology, that new 19th-century science, had figured out how one of the deadly microscopic bacteria did its damage, with a poison that could choke off children’s airways, and had invented an antidote, and that was miracle enough.

Soon after that column was published, we began to hear about a new microbial threat making it hard for people to breathe in Wuhan, China, and, well, you know the rest of the story. But now, a year later, I am — no surprise — thinking about vaccines, and how far this technology has come.

When I write about diphtheria, I usually mention that I have never seen it; by the time that I went to medical school and trained in pediatrics, it was already a historical disease in this country. My teachers could remember measles, and some of the older ones had seen polio, but no one in the 1980s in Boston was telling war stories about diphtheria.

Pertussis was different — the “P” in the DTP. Pertussis, better known as whooping cough, was still around, still something to worry about when a baby came in with a particularly bad cough, still something we worried we might miss. Once we heard the whoop, our teachers told us, we would never forget it.

And since the immunity did not last forever, either from childhood vaccines or from actual disease, and there was, at that time, no safe adult booster shot for pertussis, there was no way to protect us; whenever a child did turn out to have the disease, all the doctors and nurses and family members who had been exposed to that child would have to take a course of antibiotics, in case they had also been infected, and many pediatric residents ended up taking those antibiotics two or three times.

But you didn’t always know that you’d been exposed. In fact, I managed to catch pertussis in the line of duty and, without knowing it, to expose lots of babies and children, since I went on working when I was sick (in my own not-very-valid defense, I was just behaving in accordance with the fairly idiotic and highly macho rules of medicine, rules we can hope that the experience of Covid-19 will change forever).

The first thing you should know about the DTP vaccine is that all three of the diseases against which it protected a child — diphtheria, tetanus and pertussis — are bacterial diseases, unlike, for example, polio or smallpox, which are viral diseases. And one reason you may have been reading recently about the triumphs of polio vaccine in the 1950s, or the successful campaign to eradicate smallpox worldwide, is that the biological entities that cause those illnesses are more similar to the coronavirus that causes Covid-19 than any bacterial illness.

Still, the story of the DTP vaccine, and in particular the story of vaccinating against pertussis, has some interesting things to tell us, about how brilliant vaccine technology can be, but also how it can be studied and improved over time, and about trade-offs and controversies.

The first pertussis vaccines were developed and tested in the 1920s and 1930s and were in universal use by the end of the 1940s. And they worked. Dr. James Cherry, a distinguished research professor of pediatrics at David Geffen School of Medicine at the University of California, Los Angeles, and an expert on pertussis who has done extensive research both on the disease and on the vaccines, cites more than 36,000 pertussis deaths from 1926 to 1930 in the United States, most in young infants; from 1970 to 1974, there were 52.


Covid-19 Vaccines ›


Answers to Your Vaccine Questions

While the exact order of vaccine recipients may vary by state, most will likely put medical workers and residents of long-term care facilities first. If you want to understand how this decision is getting made, this article will help.

Life will return to normal only when society as a whole gains enough protection against the coronavirus. Once countries authorize a vaccine, they’ll only be able to vaccinate a few percent of their citizens at most in the first couple months. The unvaccinated majority will still remain vulnerable to getting infected. A growing number of coronavirus vaccines are showing robust protection against becoming sick. But it’s also possible for people to spread the virus without even knowing they’re infected because they experience only mild symptoms or none at all. Scientists don’t yet know if the vaccines also block the transmission of the coronavirus. So for the time being, even vaccinated people will need to wear masks, avoid indoor crowds, and so on. Once enough people get vaccinated, it will become very difficult for the coronavirus to find vulnerable people to infect. Depending on how quickly we as a society achieve that goal, life might start approaching something like normal by the fall 2021.

Yes, but not forever. The two vaccines that will potentially get authorized this month clearly protect people from getting sick with Covid-19. But the clinical trials that delivered these results were not designed to determine whether vaccinated people could still spread the coronavirus without developing symptoms. That remains a possibility. We know that people who are naturally infected by the coronavirus can spread it while they’re not experiencing any cough or other symptoms. Researchers will be intensely studying this question as the vaccines roll out. In the meantime, even vaccinated people will need to think of themselves as possible spreaders.

The Pfizer and BioNTech vaccine is delivered as a shot in the arm, like other typical vaccines. The injection won’t be any different from ones you’ve gotten before. Tens of thousands of people have already received the vaccines, and none of them have reported any serious health problems. But some of them have felt short-lived discomfort, including aches and flu-like symptoms that typically last a day. It’s possible that people may need to plan to take a day off work or school after the second shot. While these experiences aren’t pleasant, they are a good sign: they are the result of your own immune system encountering the vaccine and mounting a potent response that will provide long-lasting immunity.

No. The vaccines from Moderna and Pfizer use a genetic molecule to prime the immune system. That molecule, known as mRNA, is eventually destroyed by the body. The mRNA is packaged in an oily bubble that can fuse to a cell, allowing the molecule to slip in. The cell uses the mRNA to make proteins from the coronavirus, which can stimulate the immune system. At any moment, each of our cells may contain hundreds of thousands of mRNA molecules, which they produce in order to make proteins of their own. Once those proteins are made, our cells then shred the mRNA with special enzymes. The mRNA molecules our cells make can only survive a matter of minutes. The mRNA in vaccines is engineered to withstand the cell’s enzymes a bit longer, so that the cells can make extra virus proteins and prompt a stronger immune response. But the mRNA can only last for a few days at most before they are destroyed.

Even so, when I started out in pediatrics, in the 1980s, the DTP was, no question, the shot we least liked giving. Of the shots that we routinely gave, this was the one that kids tended to react to — with fevers, with sore arms, and sometimes, though very rarely, with more serious reactions. “Reactogenic,” we sometimes called it.

The reactions had a lot to do with what went into the vaccine: whole inactivated Bordetella pertussis bacteria. And though bacteria are microscopically small, they are enormous and complex cells compared to viruses, which are just made up of protein and nucleic acid (DNA or RNA). In other words, a whole-cell vaccine contained many different compounds in it that the body might react to — there are more than 3,000 different proteins in the bacterial cell. For diphtheria and tetanus, single “toxoids” were used, inactivated versions of the poisons manufactured by those bacteria, so those components were much less reactogenic.

There were parents who believed that their children had been harmed by the vaccine, and strong sentiment against it in what we would now call the anti-vaccine movement, along with ongoing medical controversy over which problems had been caused by the vaccine and which were coincidences of timing in a vaccine given at 2, 4 and 6 months of age, and then again at around a year and a half.

Since 1999, children in the United States have been vaccinated with DTaP, rather than DTP, with the “a” standing for “acellular.” No more whole cells; these vaccine developers used specific proteins to which the body would manufacture immunity. DTaP shots are significantly less “reactogenic.”

They also tend to be less effective in provoking a long-lasting effective immune response; in a 2019 review, Dr. Cherry wrote that in almost every clinical trial, the whole-cell vaccines were more efficacious than the acellular vaccines. That meant a certain balancing of risks and benefits, and ongoing discussion, as the changeover to DTaP has been linked to recent resurgences in the number of cases, though not necessarily in deaths, and Dr. Cherry argues that the increased number of reported cases may actually be a result of raised awareness and better testing. But even if there is more pertussis around in adults, thanks to the vaccines, this is no longer a deadly disease of young children.

Although a safe adult booster called the Tdap has now been developed, there is still a great deal of pertussis infection in adolescents and adults, and it often goes undiagnosed, even among doctors, because in adults it may not look that different from other coughs and colds.

But it can; for me, it was a miserable disease, though not particularly dangerous — I wasn’t at risk of dying from it, even if it was the worst cough I ever had. Adults don’t even tend to produce the characteristic “whoop,” which comes from sucking in air back across the closed glottis, after a paroxysm of coughing — if I’d been whooping, surely I would have diagnosed myself, or my colleagues at the health center would have diagnosed me.

I see this as a story that should help us appreciate the unending ingenuity of the science that finds ways to turn on our complicated immune responses without making us suffer through a disease that once choked the life out of countless babies.

At the same time we can understand that getting the most out of the body’s immune defenses can take some learning and some study, and that there can be trade-offs that you consider for the good of the individual patient or the good of the community. We vaccinate adults against pertussis now not only to protect them, but also to make sure that the vulnerable — in this case, infants — are less likely to be exposed, and in fact, vaccinating pregnant women with the adult booster turns out to be a good way to protect their newborns.

Dr. Cherry said that vaccinating all pregnant women with Tdap “will prevent virtually all deaths from pertussis in the first two months of life.”

Surely, as we live though this pandemic, we can take a moment to be grateful for the remarkable progress in vaccine technology that has given us vaccines that target Covid-19 so elegantly and specifically, and offers us ways to protect not only ourselves, but also those around us.

Pressure Grows for States to Open Vaccines to More Groups of People

Pressure Grows for States to Open Vaccines to More Groups of People

Some states are already expanding eligibility to people 65 and over, even though millions of people the C.D.C. recommends go first — health care workers and nursing home residents — have yet to get shots.

Gov. Ron DeSantis of Florida, right, during vaccinations at the John Knox Village nursing home in Pompano Beach, Fla., last month.
Gov. Ron DeSantis of Florida, right, during vaccinations at the John Knox Village nursing home in Pompano Beach, Fla., last month.Credit…Marta Lavandier/Associated Press
Abby Goodnough

  • Jan. 9, 2021, 12:00 p.m. ET

Just weeks into the country’s coronavirus vaccination effort, states have begun broadening access to the shots faster than planned, amid tremendous public demand and intense criticism about the pace of the rollout.

Some public health officials worry that doing so could bring even more chaos to the complex operation and increase the likelihood that some of the highest-risk Americans will be skipped over. But the debate over how soon to expand eligibility is intensifying as deaths from the virus continue to surge, hospitals are overwhelmed with critically ill patients and millions of vaccine doses delivered last month remain in freezers.

Governors are under enormous pressure from their constituents — especially older people, who vote in great numbers and face the highest risk of dying from the virus — to get the doses they receive into arms swiftly. President-elect Joseph R. Biden Jr.’s decision, announced Friday, to release nearly all available doses to the states when he takes office on Jan. 20, rather than holding half to guarantee each recipient gets a booster shot a few weeks after the first, is likely to add to that pressure.

Some states, including Florida, Louisiana and Texas, have already expanded who is eligible to get a vaccine now, even though many people in the first priority group recommended by the Centers for Disease Control and Prevention — the nation’s 21 million health care workers and three million residents of nursing homes and other long-term care facilities — have not yet received a shot.

On Friday afternoon, New York became the latest state to do so, announcing that it would allow people 75 and over and certain essential workers to start receiving a vaccine on Monday.

But reaching a wider swath of the population requires much more money than states have received for the task, many health officials say, and more time to fine-tune systems for moving surplus vaccine around quickly, to increase the number of vaccination sites and people who give the shots, and to establish reliable appointment systems to prevent endless lines and waits.

Some states’ expansions have led to frantic and often futile efforts by older people to get vaccinated. After Florida opened up vaccinations to anyone 65 and older late last month, the demand was so great that new online registration portals quickly overloaded and crashed, people spent hours on the phone trying to secure appointments and others waited overnight at scattered pop-up sites offering shots on a first-come first-served basis.

Similar scenes have played out in parts of Texas, Tennessee and a handful of other states.

Still, with C.D.C. data suggesting that only about a third of the doses distributed so far have been used, Alex M. Azar II, the health and human services secretary, told reporters this past week: “It would be much better to move quickly and end up vaccinating some lower-priority people than to let vaccines sit around while states try to micromanage this process. Faster administration would save lives right now, which means we cannot let the perfect be the enemy of the good.”

Boxes of Moderna’s vaccine were prepared for shipment at a distribution center in Olive Branch, Miss., last month.
Boxes of Moderna’s vaccine were prepared for shipment at a distribution center in Olive Branch, Miss., last month.Credit…Pool photo by Paul Sancya

The C.D.C. guidelines were drawn up by an independent committee of medical and public health experts that advises the agency on immunization practices; it deliberated for months about who should get vaccinated initially, while supplies were still very limited. The committee weighed scientific evidence about who is most at risk of getting very sick or dying from Covid-19, as well as ethical questions, such as how best to ensure equal access among different races and socioeconomic groups.

Although the committee’s recommendations are nonbinding, states usually follow them; in this case, the committee suggests that states might consider expanding to additional priority groups “when demand in the current phase appears to have been met,” “when supply of authorized vaccine increases substantially” or “when vaccine supply within a certain location is in danger of going unused.”

Dr. Kevin Ault, an obstetrician at the University of Kansas Medical Center who serves on the advisory committee that came up with the C.D.C. guidelines, said that it was reasonable for states to start vaccinating new groups before finishing others, but that they should be careful about exacerbating inequities and biting off more than they can chew.

“Obviously if you’re going to vaccinate that group you need to have a well-thought-out plan in hand,” he said, referring to the over-65 population. “Having people camping out for vaccine is less than ideal, I would say.”

He added, “We put a lot of thought and effort into our guidelines, and I think they are good.”

After the first vaccines were given in mid-December, a dichotomy emerged between governors who were adhering precisely to the guidelines and others who moved quickly to populations beyond health care workers and nursing home residents.

Until Friday, Gov. Andrew M. Cuomo of New York, a Democrat, had threatened to penalize hospitals that provided shots to people who are not health care workers. By contrast, Gov. Ron DeSantis of Florida, a Republican, traveled to retirement communities around his state to emphasize the importance of getting people 65 and older, who number more than five million there, immunized fast.

“In Florida we’ve got to put our parents and grandparents first,” Mr. DeSantis said at The Villages, the nation’s largest retirement community, just before Christmas.

Gov. Andrew Cuomo of New YorkCredit…Andrew Kelly/Reuters
Gov. Mike DeWine of OhioCredit…Tony Dejak/Associated Press
Gov. Greg Abbott of TexasCredit…Eric Gay/Associated Press
Gov. Larry Hogan of MarylandCredit…Jonathan Ernst/Reuters

Decisions on how soon to expand eligibility for the shots have not fallen neatly along partisan lines.


Covid-19 Vaccines ›


Answers to Your Vaccine Questions

While the exact order of vaccine recipients may vary by state, most will likely put medical workers and residents of long-term care facilities first. If you want to understand how this decision is getting made, this article will help.

Life will return to normal only when society as a whole gains enough protection against the coronavirus. Once countries authorize a vaccine, they’ll only be able to vaccinate a few percent of their citizens at most in the first couple months. The unvaccinated majority will still remain vulnerable to getting infected. A growing number of coronavirus vaccines are showing robust protection against becoming sick. But it’s also possible for people to spread the virus without even knowing they’re infected because they experience only mild symptoms or none at all. Scientists don’t yet know if the vaccines also block the transmission of the coronavirus. So for the time being, even vaccinated people will need to wear masks, avoid indoor crowds, and so on. Once enough people get vaccinated, it will become very difficult for the coronavirus to find vulnerable people to infect. Depending on how quickly we as a society achieve that goal, life might start approaching something like normal by the fall 2021.

Yes, but not forever. The two vaccines that will potentially get authorized this month clearly protect people from getting sick with Covid-19. But the clinical trials that delivered these results were not designed to determine whether vaccinated people could still spread the coronavirus without developing symptoms. That remains a possibility. We know that people who are naturally infected by the coronavirus can spread it while they’re not experiencing any cough or other symptoms. Researchers will be intensely studying this question as the vaccines roll out. In the meantime, even vaccinated people will need to think of themselves as possible spreaders.

The Pfizer and BioNTech vaccine is delivered as a shot in the arm, like other typical vaccines. The injection won’t be any different from ones you’ve gotten before. Tens of thousands of people have already received the vaccines, and none of them have reported any serious health problems. But some of them have felt short-lived discomfort, including aches and flu-like symptoms that typically last a day. It’s possible that people may need to plan to take a day off work or school after the second shot. While these experiences aren’t pleasant, they are a good sign: they are the result of your own immune system encountering the vaccine and mounting a potent response that will provide long-lasting immunity.

No. The vaccines from Moderna and Pfizer use a genetic molecule to prime the immune system. That molecule, known as mRNA, is eventually destroyed by the body. The mRNA is packaged in an oily bubble that can fuse to a cell, allowing the molecule to slip in. The cell uses the mRNA to make proteins from the coronavirus, which can stimulate the immune system. At any moment, each of our cells may contain hundreds of thousands of mRNA molecules, which they produce in order to make proteins of their own. Once those proteins are made, our cells then shred the mRNA with special enzymes. The mRNA molecules our cells make can only survive a matter of minutes. The mRNA in vaccines is engineered to withstand the cell’s enzymes a bit longer, so that the cells can make extra virus proteins and prompt a stronger immune response. But the mRNA can only last for a few days at most before they are destroyed.

Gov. Larry Hogan of Maryland, a Republican, announced Tuesday that he would immediately switch to what he called the “Southwest Airlines model” for vaccine allocation, referring to the airline’s open seating policy. “We’re no longer going to be waiting for all the members of a particular priority group to be completed,” he said, “before we move on to begin the next group in line.”

Gov. Mike DeWine of Ohio, a Republican, urged patience in a news briefing Tuesday as he declined to estimate when the state would start vaccinating people beyond the first priority group, known as “1a.”

“We’re asking every health department, ‘Don’t go outside 1a, stay within your lane,’” he said, adding about the vaccines, “This is a scarce commodity.”

By Thursday Mr. DeWine had set a date for people 80 and older to start getting the vaccine — Jan. 19 — and said he would phase in everyone 65 and older, as well as teachers, by Feb. 8.

The reasons so many doses received by states have not yet been administered to the first priority group are manifold. The fact that vaccination began around Christmas, when many hospital employees were taking vacation, slowed things. More health care workers are refusing to get the vaccine than many of their employers expected, and some hospitals and clinics received more doses than they needed but felt constrained by state rules from giving them to people outside the first priority groups. Some initially worried they could not even offer leftover doses in open vials to people in lower priority groups and let them go to waste.

Frontline health care workers and people age 65 and older waited to be vaccinated at a sports complex in Fort Myers, Fla., last month.Credit…Octavio Jones for The New York Times

And federal funding for vaccination efforts has been slow to reach states and localities: They got only $350 million through the end of last year, a little more than $1 per resident of the country. The economic rescue package that Congress passed in December included $8 billion for vaccine distribution that state health officials had long sought, but the first tranche of it, about $3 billion, is only now starting to be sent out.

“There was great funding in the development of these products, great funding in the infrastructure to ship them and get them out,” said Dr. Steven Stack, commissioner of the Kentucky Department for Public Health. “But then there was no funding provided of meaning for administering the vaccine, which is the last mile of this journey.”

The C.D.C. has recommended that a “1b” group consisting of people 75 and older and certain essential workers, including teachers, corrections officers and grocery store employees, be vaccinated next. The second group is much larger, about 50 million people. And the third recommended priority group — people 65 to 74, anyone 16 and older with high-risk medical conditions, and essential workers not already reached — numbers almost 130 million.

Pfizer and Moderna have pledged to deliver enough vaccine doses for 100 million people to each get the two necessary shots by the end of March, and many more in the second quarter. Several other vaccine candidates are far along in the pipeline, and if approved for emergency use here could help ramp up distribution more quickly.

The C.D.C. committee initially considered recommending that a wide range of essential workers get vaccinated before older Americans. Its rationale was that many essential workers are low-wage people of color, who have been hit disproportionately hard by the virus and had limited access to good health care. That sparked a backlash, and several governors, including Mr. DeSantis, quickly made clear they would cater to older people first.

Alex M. Azar, the health and human services secretary, left, and Surgeon General Jerome Adams, right, during a vaccination at George Washington University Hospital on Dec. 14.Credit…Pool photo by Jacquelyn Martin-Pool

Dr. Mark McClellan, who formerly headed the F.D.A. and now runs Duke University’s health policy center, said that while pushing ahead to vaccinate older people and other particularly vulnerable groups would accelerate the overall effort, “we’re going to be missing a lot of higher-risk individuals along the way.”

“I do worry about that becoming uneven in terms of access,” he said during a press briefing, “with lower-income groups, minority groups maybe in a tougher position if we don’t make it very easy for people in these high-risk groups to get vaccinated.”

Dr. Marcus Plescia, the chief medical officer for the Association of State and Territorial Health Officials, said he was surprised to hear federal officials like Mr. Azar and Dr. Jerome Adams, the surgeon general, advocate expanding vaccine access so broadly so soon.

“We didn’t come up with priority populations to slow things down, but because we knew there would be limited numbers of doses,” Dr. Plescia said. “If we try to do this in an equitable, fair way, it’s not going to be as fast as if our only goal is to get vaccine into as many arms as possible.”

Whether or not they are widening access now, governors are ramping up pressure on hospitals to use their allocated doses more quickly. Mr. Cuomo threatened to fine those that did not use their initial allocations by the end of this past week and not send them any more.

Mr. Hogan warned hospitals this past week, “Either use the doses that have been allocated to you or they will be directed to another facility or provider.”

A Riot Amid a Pandemic: Did the Virus, Too, Storm the Capitol?

A Riot Amid a Pandemic: Did the Virus, Too, Storm the Capitol?

Some scientists fear that the mayhem on Capitol Hill may have led to a so-called super-spreading event.

The rally on the National Mall before a mob entered the Capitol on Wednesday.
The rally on the National Mall before a mob entered the Capitol on Wednesday.Credit…Pete Marovich for The New York Times
Apoorva Mandavilli

  • Jan. 7, 2021, 3:29 p.m. ET

The mob that stormed the Capitol yesterday did not just threaten the heart of American democracy. To scientists who watched dismayed as the scenes unfolded on television, the throngs of unmasked intruders who wandered through hallways and into private offices may also have transformed the riot into a super-spreader event.

The coronavirus thrives indoors, particularly in crowded spaces, lingering in the air in tiny particles called aerosols. If even a few extremists were infected — likely, given the current rates of spread and the crowd size — then the virus would have had the ideal opportunity to find new victims, experts said.

“It has all the elements of what we warn people about,” said Anne Rimoin, an epidemiologist at the University of California, Los Angeles. “People yelling and screaming, chanting, exerting themselves — all of those things provide opportunity for the virus to spread, and this virus takes those opportunities.”

President Trump has downplayed the pandemic almost since its beginning, and many of his supporters who entered the Capitol yesterday did not appear to be wearing masks or making any effort at social distancing. Under similar conditions, gatherings held in such close quarters have led to fast-spreading clusters of infection.

But transmission of the virus has always been difficult to track. There is little effective contact tracing in the United States, and many in the crowd at the Capitol arrived from communities far from Washington.

The Black Lives Matter protests in the summer raised similar concerns. But most were held outdoors, and greater numbers of participants seemed to be masked. Research afterward suggested these were not super-spreading events.

Attendees of the rally preceding the rush to the Capitol on Wednesday also stood outdoors close together for hours, but “I’m less worried about what was happening outdoors,” Dr. Rimoin said. “The risk increases exponentially indoors.”

Rioters in the National Statuary Hall in the Capitol on Wednesday.
Rioters in the National Statuary Hall in the Capitol on Wednesday.Credit…Anna Moneymaker for The New York Times

Hundreds of rioters shouting in crowded rooms and hallways for extended periods of time can infect dozens of people at once, she and other experts said.

Three distinct groups — Capitol Police, rioters and members of Congress — “were spending time indoors, without social distancing, for long periods of time,” said Dr. Joshua Barocas, an infectious diseases physician at Boston University. The melee likely was a super-spreader event, he added, “especially given the backdrop of the highly transmissible variants that are circulating.”

Dr. Barocas was referring to a highly contagious new variant of the coronavirus, first identified in Britain. It has been spotted in several U.S. states but may well have spread everywhere in the country, making events like the Capitol riot even more risky, he said.

The idea that members of Congress may have been exposed, amid an already difficult transfer of power, particularly disturbed some scientists. “I am worried not only that it could it could lead to super spreading, but also super spreading to people who are elected officials,” said Dr. Tom Ingelsby, director of the Center for Health Security at Johns Hopkins University.

And infected members of Congress and law enforcement could have spread the virus to one another as they sheltered from the violence, he noted.

Rep. Jake LaTurner, Republican of Kansas, announced on Twitter early Thursday morning that he had tested positive for the virus. Mr. LaTurner was cloistered in the chamber with other members of Congress for much of the day.

At least a dozen of the 400 or so lawmakers and staff who were huddling in one committee room refused to wear masks even after being offered one, or wore them improperly below their chins, said Representative Susan Wild, Democrat of Pennsylvania.

They gathered in a committee room that quickly became crowded, making social distancing impossible, she said. Some of the lawmakers were unmasked, and several were shouting: “Tensions were high, and people were yelling at each other.”

“I just started getting really kind of angry, thinking about the holidays just passed, and how so many people did not spend time with their immediate families for fear of spreading,” she added, referring to her unmasked colleagues.

Representative Debbie Dingell, Democrat of Michigan, said the environment made her so nervous she sat on the floor at one point, hoping to duck whatever virus might be floating about. She has asked experts whether the lawmakers present should now quarantine, she said. She was wearing two masks, as she often does.

“I get that they think they have their individual freedoms,” she said of Republican lawmakers who eschewed masks. “It’s a rule for a reason. It’s to protect the common good.”

Electoral College votes were returned to a joint session of Congress late Wednesday.Credit…Erin Schaff/The New York Times

The risk for members of Congress will depend greatly on ventilation in the room where they sheltered, said Joseph Allen, an expert on buildings quality at the Harvard T.H. Chan School of Public Health in Boston.

“If there is a well-designed secure facility, then it would have great ventilation and filtration,” Dr. Allen said. “If it’s a place where they were just hunkered down wherever they could go that was safe, and it was not a place that was designed like that, then we don’t really know.”

It’s natural in a heart-pounding crisis to disregard risks that seem intangible or theoretical, he and other scientists noted.

“You cannot keep distance if you’re trying to leave a very intense and dangerous situation,” said Seema Lakdawala, an expert in respiratory virus transmission at the University of Pittsburgh. “You’re weighing the risk of your life over the risk of getting a virus at that moment.”

Members of Congress returned to continue the electoral count after the rioters were cleared from the Capitol. Some legislators took off their masks before giving a speech, Dr. Barocas noted, at precisely the time they needed to wear them. Talking at a high volume can expel vast quantities of aerosols, propelling them through an enclosed space.

Scientists have documented infectious aerosols suspended in air nearly 20 feet from an infected person. And a recent study from South Korea found that two people had become infected after spending just five minutes in a restaurant, 15 feet away from an infected patron.

Many Americans breathed sighs of relief as rioters departed the Capitol. Some experts feared that rioters heading back home could set off new chains of infection, perhaps impossible to track.

“We might get an inkling into how bad it might be because of the federal employees,” Dr. Barocas said. But “I don’t think that we’re going to know the extent of this super-spreader event.”

Even as the mob stormed the Capitol on Wednesday, the pandemic marked a grim milestone: The virus claimed nearly 4,000 lives, the highest daily toll thus far. The numbers are expected to keep rising.

The president has “created a culture in which people think it’s a hoax, and these basic control measures are being flouted repeatedly everywhere,” Dr. Allen said.

Don’t Let the Pandemic Stop Your Shots

the new old age

Don’t Let the Pandemic Stop Your Shots

Even as older adults await the coronavirus vaccine, many are skipping the standard ones. That’s not wise, health experts say.

Credit…Chris Lyons

  • Dec. 28, 2020, 12:12 p.m. ET

Peggy Stein, 68, a retired teacher in Berkeley, Calif., skipped a flu shot this year. Her reasoning: “How could I get the flu if I’m being so incredibly careful because of Covid?”

Karen Freeman, 74, keeps meaning to be vaccinated against shingles, but hasn’t done so. A retired college administrator in St. Louis, she quipped that “denial has worked well for me these many years.”

Sheila Blais, who lives on a farm in West Hebron, N.Y., has never received any adult vaccine. She also has never contracted the flu. “I’m such an introvert I barely leave the farm, so where’s my exposure?” said Ms. Blais, 66, a fiber artist. “If it’s not broke, don’t fix it.”

While older adults await vaccination against Covid-19, public health officials also worry about their forgoing, forgetting, fearing or simply not knowing about those other vaccines — the ones recommended for adults as we age and our immune systems weaken.

“There’s a lot of room for improvement,” said Dr. Ram Koppaka, associate director for adult immunization at the Centers for Disease Control and Prevention.

Every year, campaigns urge older adults to protect themselves against preventable infectious diseases. After all, influenza alone has killed 12,000 to 61,000 Americans annually over the past decade, most of them 65 or older, and has sent 140,000 to 810,000 people a year to hospitals.

The coronavirus pandemic has introduced another imperative. Those hospitals are filling fast with Covid-19 patients; in many places they are already swamped, their staffs overworked and exhausted.

“Knowing how stressed the health care system is, prevention is key,” said Dr. Nadine Rouphael, a vaccine researcher and infectious disease specialist at Emory University. “When we have record numbers of deaths, why would you go to a hospital for a vaccine-preventable illness?”

Yet the nation has long done a better job of vaccinating its children than its elders. The most recent statistics, from 2017, show that about one-third of adults over 65 had not received a flu shot within the past year. About 30 percent had not received the pneumococcus vaccine.

The proportion receiving the shingles vaccine, a fairly recent addition to the list, has inched up, but by 2018 only 34.5 percent of people over 60 had been vaccinated.

Moreover, Dr. Koppaka pointed out: “When you look deeper, there are longstanding, deep, significant differences in the proportion of Black and Hispanic adults getting vaccines compared to their white counterparts. It’s really unacceptable.”

Close to 40 percent of non-Hispanic whites had been vaccinated against shingles, for instance, compared with fewer than 20 percent of Blacks and Hispanics.

One might expect a group who can recall polio fears and outbreaks of whooping cough to be less hesitant to get vaccinated than younger cohorts. “You’ll probably have a different concept of vaccination from someone who never experienced what a serious viral illness can do,” Dr. Koppaka said.

When it comes to the Covid-19 vaccine, for instance, only 15 percent of those over 65 say they would definitely or probably not get it, compared with 36 percent of those 30 to 49, a Kaiser Family Foundation tracking poll showed earlier this month. (Ms. Stein, Ms. Blais and Ms. Freeman all said they would happily accept the Covid vaccine.)

But for other diseases, vaccination rates lag. Given that older people are more vulnerable to severe illness from them, why the gaps in coverage?

Internists and other doctors for adults don’t promote vaccines nearly as effectively as pediatricians do, said Dr. William Schaffner, an infectious disease specialist at Vanderbilt University. Older patients, who often see a variety of doctors, may also have trouble keeping track of when they got which shot.

Experts fear that vaccination rates may have fallen further during the pandemic, as they have among children, if older people wary of going to doctors’ offices or pharmacies skipped shots.

Financial and bureaucratic obstacles also thwart vaccination efforts. Medicare Part B covers three vaccines completely: influenza, pneumococcus and, when indicated, hepatitis B.

The Tdap and shingles vaccines, however, are covered under Part D, which can complicate reimbursement for doctors; the vaccines are easier to obtain in pharmacies. Not all Medicare recipients buy Part D, and for those who do, coverage varies by plan and can include deductibles and co-pays.

Still, older adults can gain access to most recommended vaccines for no or low cost, through doctors’ offices, pharmacies, supermarkets and local health departments. For everyone’s benefit, they should.

Here’s what the C.D.C. recommends:

Influenza An annual shot in the fall — and it’s still not too late, because flu season peaks from late January into February. Depending on which strain is circulating, the vaccine (ask for the stronger versions for seniors) prevents 40 to 50 percent of cases; it also reduces illness severity for those infected.

Thus far this year, flu activity has remained extraordinarily low, perhaps because of social distancing and masks or because closed schools kept children from spreading it. Manufacturers shipped a record number of doses, so maybe more people got vaccinated. In any case, fears of a flu/Covid “twindemic” have not yet been realized.

Nevertheless, infectious disease experts urge older adults (and everyone over six months old) to get flu shots now. “Flu is fickle,” Dr. Schaffner said. “It could take off like a rocket in January.”

Tetanus, diphtheria, pertussis. A booster of TD vaccine every 10 years, to prevent tetanus and diphtheria. If you’ve never had the Tdap vaccine — which adds prevention against pertussis — that’s the one you want. Although pertussis, better known as whooping cough, occasionally shows up in adults, newborns are particularly at risk. Pregnant women will ask expectant grandparents to get a Tdap shot. Because it is covered under Part D, a pharmacy is the best bet.

Pneumococcus. “It’s a pneumonia vaccine, but it also prevents the most serious consequences of pneumonia, including meningitis and bloodstream infections,” Dr. Koppaka said.

People over 65 should get the polysaccharide formula — brand name Pneumovax — but there are certain circumstances, such as immune-compromising conditions, to discuss with a health care provider.

Those over 65 may choose, again in consultation with a provider, to also get the conjugate pneumococcal vaccine (brand name Prevnar), which provides some additional protection. If so, C.D.C. guidelines specify which vaccine to take when.

Shingles. Social distancing won’t ward off this disease; anyone who had chickenpox, which is just about every senior, still carries the virus.

“If you live to be 80, you stand a 35 to 50 percent chance of having an episode,” Dr. Schaffner said. “And the older you are when you get it, the more apt you are to get the most serious complication” — lingering nerve pain called post-herpetic neuralgia.

The C.D.C. recommends Shingrix, the highly effective shingles vaccine the F.D.A. approved in 2017, for everyone over 50. The previous shingles vaccine has been discontinued. Get Shingrix even if you had the earlier vaccine, Zostavax, and even if you’ve had shingles — it can recur.

The two required shots, given two to six months apart, can total $300 out of pocket. But Medicare Part D beneficiaries will pay an average of $50 for the pair, said a spokesman for the manufacturer GlaxoSmithKline, and people with private insurance even less.

Hepatitis A and hepatitis B. These aren’t age-related; the vaccines are recommended for people with certain health conditions, including chronic liver disease and H.I.V. infection, or for travelers to countries where the diseases are widespread.

The hepatitis B vaccine is also recommended, at a provider’s discretion, for diabetics over 60 who haven’t been previously vaccinated. Talk to a health care professional about your risks.

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Covid Vaccine Launch Evokes Memories of Polio Era

Lynne Seymour recalls her mother jumping for joy when the polio vaccine rolled out in 1955, when she was eight. “It was like a dark cloud had lifted,” she said.
Lynne Seymour recalls her mother jumping for joy when the polio vaccine rolled out in 1955, when she was eight. “It was like a dark cloud had lifted,” she said.Credit…Rana Young for The New York Times

Vaccine Memories of Another Time and Place

Many older Americans, shut in during this year’s pandemic, share haunting recollections from the polio era of their childhood.

Lynne Seymour recalls her mother jumping for joy when the polio vaccine rolled out in 1955, when she was eight. “It was like a dark cloud had lifted,” she said.Credit…Rana Young for The New York Times

  • Dec. 25, 2020, 5:00 a.m. ET

Lizzo’s “Good As Hell” greeted the arrival of Covid-19 vaccines this month at Boston Medical Center, where the scene of dancing health care workers quickly spread on TikTok. Others shared triumphant selfies of their arms post-injection.

For Americans of a certain generation, the rollout evoked searing memories of an earlier era — one that rescued their childhood from fear and the sudden loss of classmates and siblings.

Lynne Seymour was 8 years old in 1955, when her mother, a nurse, let out a startling noise while listening to the radio at their home in Berkeley, Calif.

“She started jumping up and down, crying and laughing at the same time,” Ms. Seymour said. “It scared me a little because I didn’t know what was happening. So I said, ‘Mom, what is it?’”

Her mother explained that Dr. Jonas Salk, a medical researcher, had developed a vaccine for a dangerous virus. “It meant we wouldn’t have to worry about polio anymore, and children wouldn’t be in iron lungs and we would go back to the swimming pool,” Ms. Seymour said. “It was like a dark cloud had lifted.”

The first polio epidemic in the United States began in Vermont in 1894, an outbreak that killed 18 people and left at least 58 paralyzed. Waves of pernicious outbreaks, targeting children, would mar the next half-century. In the country’s worst single year, 1952, nearly 60,000 children were infected and more than 3,000 died. Many were paralyzed, notably including Franklin D. Roosevelt, who would become president and hide his disability. Others were consigned to life in an iron lung, a type of ventilator that encased a child’s body to ease breathing.

A litany of other celebrated figures also lived with the disease: the songwriter Joni Mitchell, the artist Frida Kahlo, the Olympic sprinter Wilma Rudolph and Senator Mitch McConnell of Kentucky.

Ms. Seymour, center, in Berkeley, Calif., in 1954, with her mother, Marie Williams, her brother, Wayne, left, and sister, Adele.
Ms. Seymour, center, in Berkeley, Calif., in 1954, with her mother, Marie Williams, her brother, Wayne, left, and sister, Adele.Credit…via Lynn Seymour

Parents anxiously wondered how to keep their children safe from the disease, ordering them to stay away from swimming pools and movie theaters. They practiced the hand-washing routines that have become all too familiar to families this year. (It is now understood that the polio virus spread through consumption of water and food contaminated by fecal matter.)

Dr. Salk made an ambitious bet that he could develop a vaccine for polio using inactivated virus, which was killed using formalin. When his trial was successful in April 1955, church bells rang and households cheered.

American children had been taught for years to dread summer because it so often brought polio outbreaks. A vaccine promised that they could go out and play again, and swim without as much worry.

Stefan Krieger, 74, remembered his family’s enthusiastic reaction to the news. Just a few years earlier, he caught a cold and had to miss a friend’s birthday party; everyone else who attended, including his best friend, contracted polio.

“Many of us had a classmate whose sister or brother had been stricken,” said Arlene Agus, 71.

Ms. Agus’s school in New York City distributed the vaccine in alphabetical order so she was the first to get the shot, with a lollipop as her reward.

“Over half-a-century later, I can still remember the expressions of relief from the long, winding chain of students standing behind me, grateful that they weren’t in my spot,” she said.

The Salk family in 1953. Jonas and Donna, and sons, from left to right, Peter, Jonathan and Darrell. Credit…via Jonathan Salk

The federal government licensed the vaccine within hours of the announcement and manufacturers began their production efforts. “An historic victory over a dread disease,” a newscaster’s voice declared in an April 12 reel from Metro-Goldwyn-Mayer. The announcement includes clips of men in suits rolling carts of vaccine shipments, much like this month’s images of coronavirus vaccine shipments. “Here scientists usher in a new medical age.”

After all of the fanfare, some children remembered getting the vaccine as anti-climactic. Philip McLeod, 77, who was living in Nanton, Alberta, at the time, said he and his classmates were lined up very quickly and then it was over. “It was hard to believe as a 12-year-old that was going to save your life, because it was so routine,” he said.

But visibly, the creek and the skating rink by his home, long abandoned out of fear — similar to the scenes today at many communal playgrounds and parks — once again filled with the sounds of children playing.

Among the first children in the country to receive the vaccine were Dr. Salk’s three sons. Peter Salk, the oldest, recalled their father gathering them near the kitchen table and instructing them to roll up their sleeves and expose their triceps. Then Dr. Salk moved from the stove, where he had sterilized needles and syringes, and injected his sons.

“It was an opportunity to demonstrate my father’s confidence in the work he had done,” Peter Salk said. “And to get us kids protected.”

Jonathan Salk, one of the vaccine researcher’s three sons. The boys were vaccinated in the family’s kitchen.  Credit…John Francis Peters for The New York Times

When the shot was later administered in a 1954 field trial at their Pittsburgh elementary school, one of the teachers asked Darrell Salk, who was only 6 at the time, to comfort a crying schoolmate and explain that his father’s vaccine was safe.

“What did I know?” Darrell said. “I was a kid. But I did my best to reassure him it was helping to protect people from a very nasty disease.”

As thousands of children began to receive the vaccine, Dr. Salk’s sons got caught up in the waves of excitement. Five-year-old Jonathan Salk called his best friend to announce the good news: “Billy! I’m famous! And so is my father!”

Still, much like the atmosphere surrounding the debut of this month’s coronavirus vaccines, introduction of the polio immunization was bittersweet for many families who had already lost relatives.

Jean Norville, 72, remembered her older brother Tommy as a “saint,” so gentle-hearted that when she slammed her finger in a car door, he said he wished it were his own instead. Tommy fell sick with polio in October 1951, and his parents drove at speeds exceeding 100 miles per hour to a hospital in Louisville, Ky., where he was put in an iron lung. Their mother, refusing to leave Tommy’s side, slept in the hospital bathtub.

He died soon afterward. The neighbors were so afraid of getting polio that Ms. Norville’s family held Tommy’s funeral with an empty coffin. When the vaccine arrived, Ms. Norville’s mother rushed her children to the health department to get the shot.

“Think of Tommy,” her mother said.

Tommy Norville, Jean’s older brother. “Our family ‘died’ in October of 1951,” she recalled, adding that few pictures remain. “My mother could not stand looking at them.”Credit…via Johnathon Norville

For Catherine Griffice, 79, the cure for polio carries a special legacy. Her father, Frederick Bland, caught the disease in 1948, when he was a third-year medical student. Paralyzed and unable to climb stairs, he was carried out of the house on a chair and taken by ambulance to a hospital, where he died four days later.

Her mother remarried, to another doctor, who then vaccinated all of their neighbors in Wittenberg, Wis. “He did it in honor of my dad,” Ms. Griffice said.

The initial polio vaccine rollout did not go smoothly. Within a month, six cases of polio had been linked to a vaccine manufactured by Cutter Laboratories in Berkeley, Calif. It was soon discovered that Cutter had failed to completely kill the virus in some vaccine batches, a mistake that caused more than 200 polio cases and 11 deaths. The surgeon general asked Cutter to issue a recall, and distribution ground to a halt.

Months later, in the summer and fall of 1955, Boston was hit by a polio outbreak, and Ellen Goodman, then 6 years old, became sick. “I remember being in bed, and I felt this electric current going up and down my arms and legs,” she said. “Then I went to move and my left leg was numb.”

Decades later, Ms. Goodman, 71, suffers post-polio syndrome, with symptoms including chronic fatigue and difficulty walking. “My life has been defined by this disease,” she said. “To think it could have been avoided.”

The vaccine program restarted months later, and polio cases fell sharply. Elvis Presley agreed to be vaccinated on national television to build public confidence in the shot. But the disease didn’t disappear. U.S. case counts rose again beginning in 1958, especially in urban areas. The country’s last case from community spread was recorded in 1979. Though two strains of polio have been eradicated, a third remains and still circulates in Afghanistan and Pakistan.

For those scarred by memories of the polio epidemic, a vaccine against Covid can’t arrive soon enough. Many older Americans, particularly vulnerable to the disease, have been shut in and separated from their children and grandchildren for much of this year.

Ms. Norville hasn’t left her home since February and is eagerly waiting for a shot. “My son said, ‘If I could, I would bring you the vaccine today.’”

For the Salk family, the relief is accompanied by a sense of pride, given their father’s role in advancing scientific understanding of immunization. But the sons are also worried about opposition to inoculation against any disease.

“He would have been delighted,” Darrell Salk said of his father. “But he would be horrified by the number of people concerned about using the vaccine. I can see him closing his eyes and shaking his head.”

Covid-19: How Much Herd Immunity is Enough?

Scientists initially estimated that 60 to 70 percent of the population needed to acquire resistance to the coronavirus to banish it. Now Dr. Anthony Fauci and others are quietly shifting that number upward.

How Much Herd Immunity Is Enough?

How Much Herd Immunity Is Enough?

Scientists initially estimated that 60 to 70 percent of the population needed to acquire resistance to the coronavirus to banish it. Now Dr. Anthony Fauci and others are quietly shifting that number upward.

Dr. Anthony S. Fauci in March. “We really don’t know what the real number is,” he said recently.
Dr. Anthony S. Fauci in March. “We really don’t know what the real number is,” he said recently.Credit…Doug Mills/The New York Times
Donald G. McNeil Jr.

  • Dec. 24, 2020, 5:00 a.m. ET

At what point does a country achieve herd immunity? What portion of the population must acquire resistance to the coronavirus, either through infection or vaccination, in order for the disease to fade away and life to return to normal?

Since the start of the pandemic, the figure that many epidemiologists have offered has been 60 to 70 percent. That range is still cited by the World Health Organization and is often repeated during discussions of the future course of the disease.

Although it is impossible to know with certainty what the limit will be until we reach it and transmission stops, having a good estimate is important: It gives Americans a sense of when we can hope to breathe freely again.

Recently, a figure to whom millions of Americans look for guidance — Dr. Anthony S. Fauci, an adviser to both the Trump administration and the incoming Biden administration — has begun incrementally raising his herd-immunity estimate.

In the pandemic’s early days, Dr. Fauci tended to cite the same 60 to 70 percent estimate that most experts did. About a month ago, he began saying “70, 75 percent” in television interviews. And last week, in an interview with CNBC News, he said “75, 80, 85 percent” and “75 to 80-plus percent.”

In a telephone interview the next day, Dr. Fauci acknowledged that he had slowly but deliberately been moving the goal posts. He is doing so, he said, partly based on new science, and partly on his gut feeling that the country is finally ready to hear what he really thinks.

Hard as it may be to hear, he said, he believes that it may take close to 90 percent immunity to bring the virus to a halt — almost as much as is needed to stop a measles outbreak.

Asked about Dr. Fauci’s conclusions, prominent epidemiologists said that he might be proven right. The early range of 60 to 70 percent was almost undoubtedly too low, they said, and the virus is becoming more transmissible, so it will take greater herd immunity to stop it.

Dr. Fauci said that weeks ago, he had hesitated to publicly raise his estimate because many Americans seemed hesitant about vaccines, which they would need to accept almost universally in order for the country to achieve herd immunity.

Now that some polls are showing that many more Americans are ready, even eager, for vaccines, he said he felt he could deliver the tough message that the return to normal might take longer than anticipated.

“When polls said only about half of all Americans would take a vaccine, I was saying herd immunity would take 70 to 75 percent,” Dr. Fauci said. “Then, when newer surveys said 60 percent or more would take it, I thought, ‘I can nudge this up a bit,’ so I went to 80, 85.

“We need to have some humility here,” he added. “We really don’t know what the real number is. I think the real range is somewhere between 70 to 90 percent. But, I’m not going to say 90 percent.”

Doing so might be discouraging to Americans, he said, because he is not sure there will be enough voluntary acceptance of vaccines to reach that goal. Although sentiments about vaccines in polls have bounced up and down this year, several current ones suggest that about 20 percent of Americans say they are unwilling to accept any vaccine.

Also, Dr. Fauci noted, a herd-immunity figure at 90 percent or above is in the range of the infectiousness of measles.

“I’d bet my house that Covid isn’t as contagious as measles,” he said.

Measles is thought to be the world’s most contagious disease; it can linger in the air for hours or drift through vents to infect people in other rooms. In some studies of outbreaks in crowded military barracks and student dormitories, it has kept transmitting until more than 95 percent of all residents are infected.

Interviews with epidemiologists regarding the degree of herd immunity needed to defeat the coronavirus produced a range of estimates, some of which were in line with Dr. Fauci’s. They also came with a warning: All answers are merely “guesstimates.”

“You tell me what numbers to put in my equations, and I’ll give you the answer,” said Marc Lipsitch, an epidemiologist at Harvard’s T.H. Chan School of Public Health. “But you can’t tell me the numbers, because nobody knows them.”

The only truly accurate measures of herd immunity are done in actual herds and come from studying animal viruses like rinderpest and foot-and-mouth disease, said Dr. David M. Morens, Dr. Fauci’s senior adviser on epidemiology at the National Institute of Allergy and Infectious Diseases.

When cattle are penned in corrals, it is easy to measure how fast a disease spreads from one animal to another, he said. Humans move around, so studying disease spread among them is far harder.

The original assumption that it would take 60 to 70 percent immunity to stop the disease was based on early data from China and Italy, health experts noted.

Epidemiologists watching how fast cases doubled in those outbreaks calculated that the virus’s reproduction number, or R0 — how many new victims each carrier infected — was about 3. So two out of three potential victims would have to become immune before each carrier infected fewer than one. When each carrier infects fewer than one new victim, the outbreak slowly dies out.

Two out of three is 66.7 percent, which established the range of 60 to 70 percent for herd immunity.

The French aircraft carrier Charles de Gaulle arriving in the port of Toulon in April, carrying infected sailors.
The French aircraft carrier Charles de Gaulle arriving in the port of Toulon in April, carrying infected sailors.Credit… Marine Nationale, via Agence France-Presse — Getty Images

Reinforcing that notion was a study conducted by the French military on the crew of the aircraft carrier Charles de Gaulle, which had an outbreak in late March, said Dr. Christopher J.L. Murray, director of the University of Washington’s Institute for Health Metrics and Evaluation.

The study found that 1,064 of the 1,568 sailors aboard, or about 68 percent, had tested positive for the virus.

But the carrier returned to port while the outbreak was still in progress, and the crew went into quarantine, so it was unclear whether the virus was finished infecting new sailors even after 68 percent had caught it.

Also, outbreaks aboard ships are poor models for those on land because infections move much faster in the close quarters of a vessel than in a free-roaming civilian population, said Dr. Natalie E. Dean, a biostatistician at the University of Florida.

More important, the early estimates from Wuhan and Italy were later revised upward, Dr. Lipsitch noted, once Chinese scientists realized they had undercounted the number of victims of the first wave. It took about two months to be certain that there were many asymptomatic people who had also spread the virus.

It also became clearer later that “superspreader events,” in which one person infects dozens or even hundreds of others, played a large role in spreading Covid-19. Such events, in “normal” populations — in which no one wears masks and everyone attends events like parties, basketball tournaments or Broadway shows — can push the reproduction number upward to 4, 5 or even 6, experts said. Consequently, those scenarios call for higher herd immunity; for example, at an R0 of 5, more than four out of five people, or 80 percent, must be immune to slow down the virus.

Further complicating matters, there is a growing consensus among scientists that the virus itself is becoming more transmissible. A variant “Italian strain” with the mutation known as D614G has spread much faster than the original Wuhan variant. A newly identified mutation, sometimes called N501Y, that may make the virus even more infectious has recently appeared in Britain, South Africa and elsewhere.

The more transmissible a pathogen, the more people must become immune in order to stop it.

Dr. Morens and Dr. Lipsitch agreed with Dr. Fauci that the level of herd immunity needed to stop Covid-19 could be 85 percent or higher. “But that’s a guesstimate,” Dr. Lipsitch emphasized.

“Tony’s reading the tea leaves,” Dr. Morens said.

The Centers for Disease Control and Prevention offers no herd immunity estimate, saying on its website that “experts do not know.”

Although W.H.O. scientists still sometimes cite the older 60 to 70 percent estimate, Dr. Katherine O’Brien, the agency’s director of immunization, said that she now thought that range was too low. She declined to estimate what the correct higher one might be.

“We’d be leaning against very thin reeds if we tried to say what level of vaccine coverage would be needed to achieve it,” she said. “We should say we just don’t know. And it won’t be a world or even national number. It will depend on what community you live in.”

Dr. Dean noted that to stop transmission in a crowded city like New York, more people would have to achieve immunity than would be necessary in a less crowded place like Montana.

Even if Dr. Fauci is right and it will take 85 or even 90 percent herd immunity to completely stop coronavirus transmission, Dr. Lipsitch said, “we can still defang the virus sooner than that.”

He added: “We don’t have to have zero transmission in order to have a decent society. We have lots of diseases, like flu, transmitting all the time, and we don’t shut down society for that. If we can vaccinate almost all the people who are most at risk of severe outcomes, then this would become a milder disease.”

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Coronavirus Variant Is Indeed More Transmissible, New Study Suggests

Coronavirus Variant Is Indeed More Transmissible, New Study Suggests

Researchers warn that the British variant is so contagious that new control measures, including closing down schools and universities, may be necessary.

A gazebo outside a bar in the West End of London on Dec. 15. The city entered Tier 3 restrictions the next day.
A gazebo outside a bar in the West End of London on Dec. 15. The city entered Tier 3 restrictions the next day.Credit…Andrew Testa for The New York Times
  • Dec. 23, 2020, 10:22 p.m. ET

A team of British scientists released a worrying study on Wednesday of the new coronavirus variant sweeping the United Kingdom. They warned that the variant is so contagious that new control measures, including closing down schools and universities, might be necessary. Even that may not be enough, they noted, saying, “It may be necessary to greatly accelerate vaccine rollout.”

The study, released by the Center for Mathematical Modeling of Infectious Diseases at the London School of Hygiene and Tropical Medicine, has not yet undergone review by a scientific journal. The study compares a series of models as predictors of data on infections, hospitalizations and other variables; other researchers are studying the variant in laboratory experiments to determine if it is biologically distinct.

The study found no evidence that the variant was more deadly than others. But the researchers estimated that it was 56 percent more contagious. On Monday, the British government released an initial estimate of 70 percent.

Bill Hanage, an epidemiologist at the Harvard T.H. Chan School of Public Health who was not involved in the study, said that it presented a compelling explanation of the past and potential future of the variant.

“The overall message of it is solid and consistent with what we’ve been seeing from other sources of information,” he said in an interview. “Does this matter? Yes. Is there evidence for increased transmission? Yes. Is that going to impact the next few months? Yes. Those are all, I think, pretty solid.”

A New Variant

A series of tiny mutations found in many British samples of the coronavirus may help the virus spread more easily. The coronavirus variant is known as B.1.1.7.

Spikes used to latch onto and enter human cells

Spike

protein

gene

CORONAVIRUS

CORONAVIRUS

GENOME

ORF1a

protein

ORF1b

protein

Spike

protein

E

M

N

Change in

RNA sequence

MUTATIONS

that led to the

B.1.1.7 variant

X

(deletion)

X

Change in

amino acid

X

Spikes used to latch onto and enter human cells

CORONAVIRUS

Spike

protein

gene

Change in

RNA sequence

Change in

amino acid

CORONAVIRUS

GENOME

N protein

M protein

E protein

Spike protein

MUTATIONS

that led to the

B.1.1.7 variant

ORF1b protein

(deletion)

ORF1a protein

By Jonathan Corum | Source: Andrew Rambaut et al., Covid-19 Genomics Consortium U.K.

The variant, which came to the attention of British researchers earlier this month, has been rapidly spreading in London and eastern England. It carries a set of 23 mutations, some of which may make it more contagious.

The authors of the study found more evidence that the variant does indeed spread more rapidly than others. For example, they ruled out the possibility that it was becoming more common because outbreaks had started in places where people were more likely to come into contact with each other. Data recorded by Google, indicating the movements of individual cellphone users over time, showed no such difference.

The researchers built different mathematical models and tested each one as an explanation for the variant’s spread. They analyzed which model of the spread best predicted the number of new cases that actually were confirmed, as well as hospitalization and deaths.

The team then projected what the new variant would do over the next six months and built models that factored in different levels of restrictions. Without a more substantial vaccine rollout, they warned, “cases, hospitalizations, I.C.U. admissions and deaths in 2021 may exceed those in 2020.”

Closing schools until February could buy Britain some time, the researchers found, but lifting those extra restrictions would then cause a major rebound of cases.

Because of the higher transmission rate, the country will need a much higher percentage of the population to get vaccinated to reach herd immunity. To reduce the peak burden on I.C.U.s, the researchers found, vaccination would need to jump to two million people per week from the current pace of 200,000.

“You need to be able to get whatever barriers to transmission you can out there as soon as possible,” Dr. Hanage said.

The researchers warned that their model was based, like any model, on a set of assumptions, some of which may turn out to be wrong. For instance, the rate at which infected people die from Covid-19 may continue to drop as doctors improve at caring for hospitalized patients. Uncertainties remain as to whether the new variant is more contagious in children, and if so, by how much.

Still, they wrote, “there is an urgent need to consider what new approaches may be required to sufficiently reduce the ongoing transmission of SARS-CoV-2.”

Alessandro Vespignani, director of the Network Science Institute at Northeastern University in Boston, who was not involved in the study, said of the new estimates, “Unfortunately, this is another twist in the plot.”

“While we were all rejoicing for the vaccine,” he added, “here is the possibility of a change of epidemiological context that makes our next few months much more complex and more perilous to navigate. Evidence is accumulating that the variant is more transmissible, and this implies that it will likely require an even greater effort to keep spreading under control.”

Dr. Hanage cautioned that the model had some shortcomings. The researchers assumed that all people younger than 20 had a 50 percent chance of spreading the disease. Although that might be true for younger children, Dr. Hanage said, it is not for teenagers. “That’s the weakest part of their model,” he said.

Nonetheless, he said, the study provided an important glimpse into the country’s possible futures. “It’s not a forecast, it’s not a prediction, it’s not saying this will happen,” he said. “It is saying that if you don’t take it seriously, this is the kind of thing that could very easily happen.”

Benjamin Mueller contributed reporting.

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Covid Vaccine During Pregnancy? Even Doctors Struggle With This Question

Doctors

I’m a Pregnant Doctor. Should I Get the Covid Vaccine?

A doctor struggles with the lack of data surrounding the Covid-19 vaccine and pregnancy.

Credit…Nam Y. Huh/Associated Press

  • Dec. 22, 2020, 5:00 a.m. ET

The morning after the Food and Drug Administration approved the emergency use authorization of the first coronavirus vaccine, I awoke to a message from my hospital asking me to sign up for an appointment to get vaccinated.

It brought tears to my eyes. As a primary care doctor, I haven’t exactly been on the front lines of the Covid-19 fight, but it’s upended my life and the lives of my patients. With the vaccine’s approval — and now a second one — we finally have an end in sight. Within hours, my colleagues were all texting each other, abuzz with the excitement of scheduling their vaccine appointments.

But I quickly learned I have an impossible choice ahead of me.

I am pregnant, and all of the clinical trials on Covid-19 vaccines excluded pregnant people. This is no surprise: pregnant people are frequently left out of clinical research because of the complexity of pregnancy, including concerns about potential harm to the fetus. That leaves us with little data to help us make decisions about medications and vaccines.

Instead we’re on our own, winging it during an already vulnerable time. And as I care for a ballooning number of coronavirus-positive patients each day, my decision about the vaccine seems more urgent than ever.

The news of my pregnancy was a joyful moment for my family in a difficult year, but Covid-19 has been a terrifying backdrop. I practice in Camden, N.J., and our community has been hard-hit. Infections are soaring above the springtime peak. My inbox contains positive case after positive case.

My patients are the most essential of essential workers — home health aides, warehouse workers, janitors — still, even after all we’ve learned this year, with little job security, minimal paid sick leave and inadequate personal protective equipment. And as my patients get exposed to the virus, so do I.

The data on coronavirus infection during pregnancy are not reassuring. Pregnant people who get the virus seem to have a higher risk for severe symptoms and complications, and there also may be a small increased risk of preterm birth. Each day I walk into my clinic, I ask myself, “Will this be the day I get it?”

The early news about the efficacy of the vaccines was thrilling. But there has been little data on how the vaccine affects pregnant people. No pregnant patients were enrolled in the early trials, although some people got pregnant during the course of the study. Researchers are monitoring them to see how they do.

According to Ruth Faden, a Johns Hopkins bioethicist who studies vaccine policy, the reluctance to include pregnant research subjects in clinical trials has a long history.

“There’s an inertia that’s set in,” she told me. Studying pregnant people requires extra effort in safe study design and recruitment efforts, so rather than do the hard work, she says, pregnant women are often just excluded altogether.

“It’s an ethically complex situation,” she added. “Pregnancy is like nothing else. Anything you do to a pregnant woman also has a chance of affecting the developing offspring.”

Researchers estimate we have adequate data on the risk of birth defects in less than 10 percent of medications approved by the Food and Drug Administration since 1980. That means any time a pregnant person thinks about using a medication or vaccine, she might feel like she’s making a decision at random, without any rigorous information to guide her.

That’s certainly how I feel right now. My medical training taught me to respect my patients’ autonomy; I see my job as guiding them through confusing medical information and helping them make decisions, not making decisions for them. Patient autonomy is a primary value in medicine.

I was glad to see that the F.D.A. left the choice of whether or not to get the Covid-19 vaccine up to pregnant women, rather than excluding us from eligibility altogether. For a pregnant nursing home aide, or a pregnant intensive care unit nurse, the risk of getting Covid-19 might be greater than the risk of any potential vaccine side effects.

This isn’t a theoretical exercise for hundreds of thousands of health care workers. Women make up an estimated 76 percent of the health care work force, many of us of childbearing age. I have text message chains with several pregnant and breastfeeding physician friends, all of us trying to sort through the limited information we have.

But without any data to guide me, my autonomy to make the decision doesn’t feel as meaningful. The American College of Obstetricians and Gynecologists offered this wildly unsatisfying recommendation: “Covid-19 vaccines should not be withheld from pregnant individuals who meet criteria for vaccination.” The Centers for Disease Control and Prevention issued similarly noncommittal guidance: “Health care personnel who are pregnant may choose to be vaccinated.” Both are a far cry from the two organizations’ enthusiastic support for the flu vaccine in pregnancy, for example.

So it’s up to me and my nurse midwife, both of us smart clinicians, but not vaccine experts. I asked her what she thought, and she told me, “Honestly, I have no idea.”

I try to weigh the costs and benefits: I care for positive patients, but it’s not as if I’m an I.C.U. doctor. Many vaccines are safe in pregnancy — I gladly got my flu shot early on — but other vaccines aren’t. How can I weigh the costs and benefits if I don’t know what the costs are?

The two vaccines that have now been approved use a novel messenger RNA technology that has not been studied in pregnancy. It’s possible the mRNA and the bubble it travels in, made of lipid nanoparticles, could cross the placenta, according to Dr. Michal Elovitz, a preterm labor researcher and obstetrician at the University of Pennsylvania. This might, in theory, cause inflammation in utero that could be harmful to the developing fetal brain.

Or, the lipid nanoparticles might not cross the placenta, Dr. Elovitz says. It’s also possible the new vaccines could be totally safe in pregnancy, like the flu shot. We just don’t have the data yet.

“To avoid having pregnant people guess, we should be advocating for more preclinical and clinical research focused on pregnant patients,” she told me.

My bottom line: If I have the chance, I’ll gladly enroll in a clinical trial of a Covid-19 vaccine for pregnant people. It’s a choice that feels much more grounded in science than trying to figure this out on my own, because I’d be making it alongside the expertise of the scientists designing the trial.

I’d feel reassured that experts in immunology and pregnancy physiology had determined the safest trimester to get the vaccine. I’d feel reassured that they had done that using evidence from animal studies, and I’d feel reassured by the ethics board that approved the trial. It wouldn’t be a risk-free decision, but it would make me feel like it wasn’t a totally reckless one.

Until then, I’ll take care of my patients with my mask, my face shield, and my gloves, hoping I don’t get infected, thinking every day about my health and the health of my baby.

Dr. Mara Gordon is a family physician in Camden, N.J.

Now That Grandma Has Been Vaccinated, May I Visit Her?

Now That Grandma Has Been Vaccinated, May I Visit Her?

The start of a mass coronavirus vaccination campaign at U.S. nursing homes has brought hope to many families. But it may be a while before restrictions loosen. Here are answers to common questions.

Vera Leip, 88, of Pompano Beach, Fla., received the Pfizer-BioNtech vaccine at the John Knox Village retirement community last week.
Vera Leip, 88, of Pompano Beach, Fla., received the Pfizer-BioNtech vaccine at the John Knox Village retirement community last week.Credit…Joe Raedle/Getty Images

  • Dec. 21, 2020, 4:48 p.m. ET

A watershed moment has arrived for many families: This week health care workers from CVS and Walgreens, under contract from the federal government, will fan out to nursing homes across the country to begin vaccinating residents against the coronavirus. The shots not only will help protect the nation’s elderly and infirm — and the staff who care for them — but they raise the prospect of ending the devastating isolation many residents have felt for months.

Family members are hopeful that before too long, they will return to visiting parents and grandparents, aunts, uncles and other loved ones regularly again. We checked with experts on some common questions.

Will restrictions on visiting be lifted soon?

Probably not in a big way. Restrictions vary by state, and the federal government’s guidance on what it considers safe stands for now. They already allow visits under certain conditions. The Centers for Medicare & Medicaid Services, or C.M.S., recommended in September that outdoor visits with residents be allowed and indoor visits, too, if the facility has been free of cases for 14 days.

Some medical experts have said that those guidelines are too lax and that visits should be severely restricted, even banned. However, some of these experts are now saying that the vaccine changes the equation, somewhat.

“Once all residents are vaccinated, it opens the door for loosening of restrictions,” said Dr. Michael Wasserman, the immediate past president of the California Association of Long Term Care Medicine, a geriatrician and former executive at nursing home chains.

To allow visits, Dr. Wasserman recommends all residents of a nursing home should be vaccinated (unless they have some condition or allergy that would discourage vaccination on medical grounds); all staff members should be vaccinated; the nursing home should have the ability to ensure that visitors test negative for the coronavirus and have been disciplined about wearing a mask in public settings.

Is the vaccine safe and effective for old and frail residents of nursing homes?

The clinical trials of the Pfizer and Moderna vaccine included people over 65, and results showed it to be safe and to work as well in older people as in younger ones.

“This vaccine has gone through testing and clinical trials to ensure it meets the highest safety standards. It also is safe to get if you already had the virus,” says a campaign to encourage people to get the shots by the American Health Care Association and National Center for Assisted Living, a combined trade group representing nursing homes and assisted-living communities.

The lead administrator for C.M.S., Seema Verma, reinforced the confidence in the shot for older patients, including those with health conditions, in a statement last week: “I urge states to prioritize nursing homes and vulnerable seniors in their distribution of the vaccine.”

The point is echoed by Dr. Sabine von Preyss-Friedman, chief medical officer of Avalon Health Care Group, which operates nursing homes, who said the new vaccines appear “safe and effective.”

If restrictions are eased, should I visit right away?

The Pfizer and Moderna vaccines both require two injections — the initial shot and a booster three or four weeks later. Dr. von Preyss-Friedman recommends waiting at least two weeks after the second shot to have a visit.

“You hope these vaccines work, but these are elderly patients,” she said. “You want to err on the side of protection.”

She said that, ideally, the visitor would also be vaccinated as well. Since shots won’t be widely available for a few months, it may be best to wait until you get your vaccine. Until then, she believes nursing homes should consider visits on a case-by-case basis.

Would visitors still need to wear a mask?

Absolutely, medical experts said. This is particularly true if they are not vaccinated, but even after they are vaccinated “until rates in the community go down,” said Dr. Joshua Uy, a geriatrician and associate professor at the University of Pennsylvania Medical School and the medical director of Renaissance Healthcare & Rehabilitation Center, a nursing home in Philadelphia.

Dr. Uy said that he hopes that the federal government would supply enough personal protective equipment so that all visitors and residents could be properly gowned for such visits.

What is being done to encourage nursing home residents to get vaccinated?

The combined nursing-home and assisted-living trade group has started a program aimed at helping nursing homes and other care facilities to explain to residents the essential need to get the vaccine. The campaign, #getvaccinated, notes: “The elderly population has a much higher risk for getting very sick, being hospitalized, or dying from Covid-19. The vaccine has been shown to provide a great deal of protection against serious illness due to Covid-19.”

But the people they love most may have more effective persuasive powers. Families can help, Dr. Uy said, by encouraging their parents and grandparents in nursing homes to get vaccinated.

“The vaccine,” he said, “is going to be our way out.”

Frontline Workers and People Over 74 Should Get Shots Next, CDC Panel Says

Frontline Workers and People Over 74 Should Get Shots Next, CDC Panel Says

The recommendation was a compromise aimed at getting the coronavirus vaccine to the most vulnerable of two high-risk groups.

Director of nursing education Loraine Hopkins Pepe, left, administers the Pfizer BioNTech COVID-19 vaccine to Dr. Richard Fine, head of anesthesiology, at Einstein Medical Center in Philadelphia, PA.
Director of nursing education Loraine Hopkins Pepe, left, administers the Pfizer BioNTech COVID-19 vaccine to Dr. Richard Fine, head of anesthesiology, at Einstein Medical Center in Philadelphia, PA.Credit…Hannah Yoon for The New York Times
  • Dec. 20, 2020, 3:40 p.m. ET

Striking a compromise between two high-risk population groups, a panel advising the Centers for Disease Control and Prevention voted Sunday to recommend that people 75 and older be next in line to receive the coronavirus vaccine in the United States, along with about 30 million “frontline essential workers,” including emergency responders, teachers and grocery store employees.

The debate about who should receive the vaccine in these early months has grown increasingly urgent as the daily tally of cases has swelled to numbers unimaginable even a month ago. The country has already begun vaccinating health care workers, and on Monday, CVS and Walgreens were to begin a mass vaccination campaign at the nation’s nursing homes and long-term care facilities. This week roughly six million doses of the newly authorized Moderna vaccine are to start arriving at more than 3,700 locations around the country, including many smaller and rural hospitals.

The panel of doctors and public health experts had previously indicated it would recommend a much broader group of Americans defined as essential workers — about 87 million people with jobs designated by a division of the Department of Homeland Security as critical to keeping society functioning — as the next priority population and that elderly people who live independently should come later.

But in hours of discussion on Sunday, the committee members concluded that given the limited initial supply of vaccine and the higher Covid-19 death rate among elderly Americans, it made more sense to allow the oldest among them to go next along with workers at the highest risk of exposure to the virus.

Groups of essential workers, such as construction and food service workers, the committee said, would be eligible for the next wave. Members did clarify that local organizations had great flexibility to make those determinations.

“I feel very strongly we do need to have that balance of saving lives and keeping our infrastructure in place,” said Dr. Helen Talbot, a member of the panel and infectious-disease specialist at Vanderbilt University.

Together, the two groups the committee voted to prioritize on Sunday number about 51 million people; federal health officials have estimated that there should be enough vaccine supply to inoculate all of them before the end of February.

Still, as the first week of vaccinations in the U.S. came to a close, frustrations were flaring about the pace of distribution. Some 128,000 shots had been given in the as of Friday, according to a New York Times database tracking vaccinations — a total that was just slightly more than half the number of new cases reported across the country that same day.

This weekend Gen. Gustave F. Perna, who heads the Trump administration’s distribution effort, apologized for more than a dozen states learning at the last minute that they would receive fewer doses next week of the vaccine manufactured by Pfizer than they had expected. Tensions were also broiling in some states over local decisions regarding which health care workers should get their shots immediately and which should wait.

The director of the C.D.C., Dr. Robert Redfield, will review the panel’s recommendation and decide, likely by Monday, whether to embrace it as the agency’s official guidance to states. The panel, the Advisory Committee on Immunization Practices, emphasized that its recommendations were nonbinding and that every state would be able to fine-tune or adjust them to serve the unique needs of its population.

The 13-to-1 vote came as frustrations flared about the pace of vaccine distribution. Some 128,000 shots have been given in the first five days of the vaccine United States, according to a New York Times database tracking vaccinations — just slightly more than half the number of new cases reported across the country on Friday alone. This weekend, Gen. Gustave F. Perna, who heads the Trump administration’s distribution effort, apologized for at least 14 states learning at the last minute that they would receive fewer doses of the vaccine manufactured by Pfizer next week than they had expected. Tensions were also flaring in some states over local decisions regarding which health care workers should get their shots immediately, and which should wait.

In addition to teachers, firefighters and police, a subgroup of the committee suggested that “frontline essential workers” should include school support staff; day care, corrections personnel, public transit, grocery store and postal workers; and those in working in food production and manufacturing. But the group’s official recommendation is not that specific.

Originally, the committee had signaled last month that they had been inclined to let 87 million essential workers receive vaccines ahead of adults 65 and older. Many had expressed their alarm that essential workers, who are often low-wage people of color, were being hit disproportionately hard by the virus and additionally were disadvantaged because of their lesser access to good health care.

general population.”

Covid Guide: How to Get Through the Pandemic

Dec. 18, 2020

Hang in there, help is on the way

Times are tough now, but the end is in sight. If we hunker down, keep our families safe during the holidays and monitor our health at home, life will get better in the spring. Here’s how to get through it.

Tara Parker-Pope

Illustrations by Vinnie Neuberg

Everyone is tired of living like this. We miss our families and our friends. We miss having fun. We miss kissing our partners goodbye in the morning and packing school lunches. We miss travel and bars and office gossip and movie theaters and sporting events.

We miss normal life.

It has been a long, difficult year, and there are many tough weeks still ahead. The coronavirus is raging, and the United States is facing a grim winter, on track for 450,000 deaths from Covid-19 by February, maybe more.

But if we can safely soldier through these next few months, then normal life — or at least a new version of normal — will be within reach. New vaccines that are highly protective against coronavirus are being rolled out right now, first to health care workers and the most vulnerable groups, and then to the general population this spring.

“Help is on the way,” says Dr. Anthony S. Fauci, the nation’s top infectious disease expert. “A vaccine is literally on the threshold of being implemented. To me that is more of an incentive to not give up, but to double down and say, ‘We’re going to get through this.’”

The vaccine won’t change life overnight. It will take months to get enough people vaccinated so that the virus has nowhere to go. But the more everyone does their part to slow down the virus now — by wearing a mask and restricting social contacts — the better and faster the vaccine will work to slow the pandemic once we can all start getting vaccinated this spring.

“Why would you want to be one of the people who is the last person to get infected?” says Dr. Fauci. “It’s almost like being the last person to get killed in a war. You want to hang in there and protect yourself, because the end is in sight.”

(1)

Hunker Down for a Little Bit Longer

The pandemic is surging, but as bad as things are, the end is in sight. By doubling down on precautions, we can slow the virus and save lives.

A crucial number to watch this winter is the test positivity rate for your state and community. The number represents the percentage of coronavirus tests that are positive compared to the overall number of tests being given, and it’s an important indicator of your risk of coming down with Covid-19. When positive test rates in a community stay at 5 percent or lower for two weeks, you’re less likely to cross paths with an infected person. Since the fall, the national test positivity rate has crept above 10 percent, and it’s been 30 percent or higher in several states.

Rising case counts and rising test positivity rates mean there is more virus out there — and you need to double down on precautions, especially if you have a high-risk person in your orbit. Cut back on trips to the store or start having groceries delivered. Scale back your holiday plans. Don’t invite friends indoors, even for a few minutes. Always keep six feet of distance from people who don’t live in your home. Skip haircuts and manicures until the numbers come down again. Wear a mask.

Close your leaky bubble.

Here’s the harsh reality of virus transmission: If someone in your family gets sick, the infection probably came from you, another family member or someone you know. The main way coronavirus is transmitted is through close contact with an infected person in an enclosed space.

“One of the challenges we have is that familiarity is seen as being a virus protector,” said Michael Osterholm, a member of President-elect Joseph R. Biden Jr.’s coronavirus advisory group and director of the Center for Infectious Disease Research and Policy at the University of Minnesota. “More likely than not, knowing someone is the risk factor for getting infected.”

This summer, 47 percent of Americans said they had formed a “pod” or social “bubble” that includes two or more households committed to strict precautions so the group can safely socialize indoors.But sometimes your bubble is leakier than you realize. Farhad Manjoo, an opinion columnist for The Times, had initially assumed his bubble was pretty small, but it turned out that he was having direct or indirect contact with more than 100 people.

Whether your bubble is just your immediate household — or you’ve formed a bubble with others — take some time to check in with everyone and seal the leaks. This requires everyone to be honest about the precautions they’re taking (or not taking). Dr. Osterholm said that convincing people that their friends might infect them has been one of the biggest challenges of the pandemic. He told the story of a man and a woman who both contracted Covid-19 after attending a wedding.

“He told me, ‘We didn’t fly. I knew everybody there,’” said Dr. Osterholm. “He somehow had the mistaken belief that by knowing the person, you won’t get infected from them. We’ve got to break through that concept.”

Mask up. You’re going to need it for a while.

A study by the Institute for Health Metrics and Evaluation at the University of Washington estimated that 130,000 lives could be saved by February if mask use became universal in the United States immediately.

Various studies have used machines puffing fine mists to show that high-quality masks can significantly reduce the spread of pathogens between people in conversation. And the common-sense evidence that masks work has become overwhelming. One well-known C.D.C. study showed that, even in a Springfield, Mo., hair salon where two stylists were infected, not one of the 139 customers whose hair they cut over the course of 10 days caught the disease. A city health order had required that both the stylists and the customers be masked.

Choose a mask with two or three layers that fits well and covers your face from the bridge of your nose to under your chin. “Something is better than nothing,” said Linsey Marr, professor of civil and environmental engineering at Virginia Tech and one of the world’s leading aerosol scientists. “Even the simplest cloth mask of one layer of material blocks half or more of aerosols we think are important to transmission.”

Watch the clock, and take the fun outside.

When making decisions about how you’re spending your time this winter, watch the clock. If you’re spending time indoors with people who don’t live with you, wear a mask and keep the visit as short as possible. (Better yet, don’t do it at all.) Layer up, get hand warmers, some blankets, an outdoor heater — and move social events outdoors.

In an enclosed space, like an office, at a birthday party, in a restaurant or in a church, you can still become infected from a person across the room if you share the same air for an extended period of time. There’s no proven time limit that is safest, but based on contact tracing guidelines and the average rate at which we expel viral particles — through breathing, speaking, singing and coughing — it’s best to wear a mask and keep indoor activities, like shopping or haircuts, to about 30 minutes.

Take care of yourself, save a medical worker.

The country’s doctors, nurses and other health care workers are at a breaking point. Long gone are the raucous nightly cheers, loud applause and clanging that bounced off buildings and hospital windows in the United States and abroad — the sounds of public appreciation each night at 7 for those on the pandemic’s front line.

“Nobody’s clapping anymore,” said Dr. Jessica Gold, a psychiatrist at Washington University in St. Louis. “They’re over it.”

In interviews, more than two dozen frontline medical workers described the unrelenting stress that has become an endemic part of the health care crisis nationwide. Jina Saltzman, a physician assistant in Chicago, said she was growing increasingly disillusioned with the nation’s lax approach to penning in the virus. In mid-November, she was astounded to see crowds of unmasked people in a restaurant as she picked up a pizza. “It’s so disheartening. We’re coming here to work every day to keep the public safe,” she said. “But the public isn’t trying to keep the public safe.”

(2)

Scale Back Your Holiday Plans

How and when the pandemic ends will depend on the choices we make this winter, particularly around Christmas and New Year’s Eve.

Nobody wants to open presents by Zoom, light holiday candles at home alone or clink virtual champagne glasses to ring in the New Year.

But here we are, in the midst of a surging pandemic, on course to losing nearly a half million souls in less than a year. Despite the promise of a vaccine on the horizon, only a tiny fraction of Americans will be vaccinated by the end of December. Vaccines won’t enter large-scale distribution until spring 2021.

The only way to drive down infection rates for now will be to avoid large indoor gatherings, wear masks, cancel travel and limit your holiday celebrations to just those who live in your home.

Dr. Fauci said he, his wife and three daughters, who live in different parts of the country, all made a family decision not to travel for the holidays. It will be the first Christmas in 30 years that the entire family won’t be together.

“I’m a person in an age group that’s at high risk of serious consequences,” said Dr. Fauci. “That’s the first Thanksgiving since any of my three daughters were born that we have not spent it as a family. That was painful, but it was something that needed to be done. We are going to do the same thing over Christmas for the simple reason that I don’t see anything changing between Thanksgiving and Christmas and Hanukkah. In fact, I see it getting worse.”

If you do travel, get tested.

People who choose to travel over the holiday season despite the warnings should consider taking precautions. First, try to quarantine for at least a week (two weeks if possible) before your trip or visit with another household. The C.D.C. now recommends that domestic air travelers get tested before and after their trip.

Remember, a lot can go wrong between the time you take a test and the moment you hug Grandma. Not only are false negatives possible, you need to consider the risk of catching the virus after taking the test — in an airport, in a plane or from a taxi driver or rental car agent.

For a laboratory test, check the turnaround time in your area and try to schedule it as close as possible to your visit. If you’re using rapid testing, try to take more than one test over the days leading up to your visit, and if possible, get a rapid test on the same day you plan to visit family, friends or a vulnerable person. Test again after you arrive if you can.

Plan a safer holiday gathering.

If you’re determined to have people to your home for the holidays, keep the guest list small and consider these precautions.

Get tested: If testing is available in your area, consider asking all guests to be tested a few days before the holiday, timing it so they get the results before coming to your home. If rapid testing is available, get tested a few times during the week and on the day of the social event.

Move the event outside: Even if it’s cold outside, try hosting all or part of your holiday celebration outdoors. Look into space heaters and fire pits to warm a porch or patio. Even a partially open space, like a screened-in porch or a garage with the door open, is better than socializing indoors. If you decide to stay indoors, open the windows and turn on exhaust fans to help ventilate your home.

Wear masks: All guests should wear a mask when not eating. If you’re the host, set the example and put your mask on after the meal is over and everyone is enjoying the conversation. Limit the amount of time you spend together indoors.

Socialize outdoors the Scandinavian way.

In the pandemic, rather than feeling depressed that the arrival of cold weather will mean that you’ll be isolated indoors, apart from friends and family, we can take lessons from Scandinavians about how to continue getting together outdoors.

(3)

Take Care of Yourself at Home

Covid-19 can be scary, but we’ve learned a lot about how to monitor the illness and home — and when to seek hospital care.

Since the start of the pandemic, we’ve learned a lot about how to care for people infected with Covid-19. Death rates from the disease are dropping as doctors have gotten better at treating it and advising patients when to seek medical care.

Steroids like dexamethasone have lowered the number of deaths among hospitalized patients by about one-third. And although limited in supply, monoclonal antibodies, a treatment given to President Trump when he was ill with coronavirus, can possibly shorten hospital stays when given early in the course of infection.

But the vast majority of patients with Covid-19 will manage the illness at home. Check in with your doctor early in the course of your illness, and make a plan for monitoring your health and checking in again if you start to feel worse.

Get tested if you have symptoms.

Ideally, you should be able to get a coronavirus test whenever you want it. But in the United States, test availability varies around the country, depending on whether supplies are low or labs are overwhelmed. Check with your doctor, an urgent care clinic or your local health department about where to get tested in your area.

If you feel sick, you should be tested for Covid-19. A dry cough, fatigue, headache, fever or loss of sense of smell are some of the common symptoms of Covid-19. After you take your test, stay isolated from others and alert the people you’ve spent time with over the last few days, so they can take precautions while you’re waiting for your result. Many tests will work best if you are in the first week of your symptoms.

Track your symptoms.

Marking your calendar at the first sign of illness, and tracking your symptoms and oxygen levels, are important steps in monitoring a coronavirus infection. Covid-19 has been unpredictable in the range of symptoms it can cause. But when it turns serious, it often follows a consistent pattern.

While every patient is different, doctors say that days five through 10 of the illness are often the most worrisome time for respiratory complications of Covid-19. Covid-19 is a miserable illness, and it’s not always easy to know when to go to the emergency room. It’s important during this time to stay in touch with your doctor. Telemedicine makes it possible to consult with your doctor without exposing others to your illness.

Get a fingertip pulse oximeter.

The best way to monitor your health during Covid-19 is to use a pulse oximeter, a small device that clips onto your finger and measures your blood oxygen levels. If it drops to 93 or lower, it could be a sign that your oxygen levels are dropping. Call your doctor or go to the emergency room.

Pro tip: One of the things to remember about reading a pulse oximeter is that many of them are designed to be read by someone facing you, not the person wearing it. If you’re looking at it upside down, a healthy reading of 98 could look like an alarming 86.

Caring for someone with Covid-19

Caring for someone with mild to moderate symptoms of the coronavirus is similar to caring for someone with the flu. Give them supportive care, fluids, soups and Tylenol, and have them take their temperature and monitor oxygen levels with a pulse oximeter regularly. Always wear a mask in the sick person’s room even if they are not there or have recovered. Coronavirus particles can last as long as three days on various surfaces, and can be shaken loose when you pick up clothes, change bedding or pick up soiled tissues.

The plight of “Covid long-haulers”

It’s unclear how many people develop lingering and sometimes debilitating symptoms after a bout of Covid-19. Such symptoms — ranging from breathing trouble to heart issues to cognitive and psychological problems — are already plaguing an untold number of people worldwide. Even for people who were never sick enough to be hospitalized, the aftermath can be long and grueling, with a complex and lasting mix of symptoms.

There is an urgent need to address long-term symptoms of the coronavirus, leading public health officials say, warning that hundreds of thousands of Americans and millions of people worldwide might experience lingering problems that could impede their ability to work and function normally.

(4)

Look for Better Days This Spring

With the rollout of the vaccine, an end to the pandemic is in sight. Life will start to feel more normal in mid- to late 2021, depending on how many people get vaccinated.

Earlier this month, The Times spoke with Dr. Fauci about his predictions for the spring. Here’s what he had to say.

The end game for viral disease outbreaks, particularly respiratory diseases, is a vaccine. We can do public health measures that are tempering things, waiting for the ultimate showstopper, which is a vaccine. That’s why I’m saying we need to double down even more on public health measures to get us through to the period when enough people in this country will be vaccinated that the virus will have no place to go. It will be a blanket or an umbrella of herd immunity.

We have crushed similar outbreaks historically. We did it with smallpox. We did it with polio. We did it with measles. We can do it with this coronavirus. It requires a highly efficacious vaccine. Thank goodness we have that. We have multiple vaccines, two of which clearly are very efficacious, and I feel confident that the others that are coming along will be comparably efficacious.

Then the second part of that is getting the overwhelming majority of the population vaccinated. I think that likely will have to be about 70 to 75 percent of people in this country. If we do that, that will be the indicator of when things will get back to normal, when you won’t have to worry about going in a restaurant, when you won’t have to worry about having a dinner party, when the children won’t have to worry about going to school, when factories can open and not worry about their employees getting sick and going to the hospital. That will happen, I guarantee you. If people appreciate the importance of getting vaccinated, and we have a high uptake of vaccines, that will happen. That’s what the future will look like.

The future doesn’t need to be bleak. It’s within our hands to really shape the future, both by public health measures and by taking up the vaccine. — Dr. Fauci

What you need to know about the new vaccines

There aren’t enough doses right now for everyone, so initially the vaccine will be rationed for those who need it most. It will take time to produce and distribute the vaccine, and then schedule two vaccinations per person, three to four weeks apart. As more vaccines get approved, things will speed up. At least 40 million doses (enough for 20 million people) should be available from Pfizer and Moderna by the end of the year, and much more will come in 2021.

The challenges ahead for widespread vaccination

The success of the new vaccines will depend on more than how well they performed in a clinical trial. While there’s much reason for optimism, a lot can still go wrong.

First there’s the challenge of manufacturing and distributing the doses. Pharmaceutical manufacturers have struggled to ramp up vaccine production. They have run short on materials like the bags that line the containers in which the vaccines are made. Both of the leading vaccines must be stored in freezing conditions. And state and local governments have to figure out how to get the vaccines from production facilities into people’s arms.

The dark cloud hanging over vaccine distribution

The vaccines will be much less effective at preventing death and illness in 2021 if they are introduced into a population where the coronavirus is raging — as is now the case in the United States.

An analogy may be helpful here, says David Leonhardt, who writes The Morning newsletter for The Times. He explains that a vaccine that’s 95 percent effective, as Moderna’s and Pfizer’s versions appear to be, is a powerful fire hose. But the size of a fire is still a bigger determinant of how much destruction occurs.

Even if the vaccine is distributed at the expected pace, at the current infection level, experts predict that the country would still face a terrible toll during the six months after the vaccine was introduced. Almost 10 million or so Americans would contract the virus, and more than 160,000 would die.

There is one positive way to look at this: Measures that reduce the virus’s spread — like mask-wearing, social distancing and rapid-result testing — can still have profound consequences. They can save more than 100,000 lives in coming months.

Hoping vaccine skepticism will fade

Despite images of relieved health care workers getting a shot in the arm flashing across TV screens and news sites, a new survey finds that more than one-quarter of Americans say they probably or definitely will not get a coronavirus vaccination. The survey, by the Kaiser Family Foundation, found that Republican, rural and Black Americans were among the most hesitant to be vaccinated.

Nevertheless, confidence in the vaccine appears to be rising. Over all, 71 percent of respondents said they definitely would get a vaccination, an 8 percent increase from what Kaiser found in a September survey. Roughly a third (34 percent) now want the vaccine as soon as possible. A recent study from Pew Research showed that about 60 percent of Americans would definitely or probably get a vaccine, up from 51 percent of people asked in September.

Looking ahead to spring

While the majority of Americans won’t get their shots until spring, the vaccine rollout is a hopeful sign of better days ahead. We asked Dr. Anthony S. Fauci, as well as several epidemiologists and health and science writers for The Times, for their predictions about the months ahead. Here’s some of what they had to say.

When can we go to the movies or the theater?

“It depends on the uptake of the vaccine and the level of infection in the community. If you go to April, May, June and you really put on a full-court press and try to vaccinate everybody within a period of a few months, as you go from second to third quarter of the year, then you could likely go to movies, go to theaters, do what you want. However, it’s unlikely, given what we’re hearing about people’s desire to get vaccinated, that we’re going to have that degree of uptake. If it turns out that only 50 percent get vaccinated, then it’s going to take much, much longer to get back to the kind of normality that we’d like to see.” — Dr. Fauci

What did you learn from pandemic life?

“Staying home with my children has taught me that life with fewer errands to run and activities to partake in is kind of nice. I think in the future we will cut down on our family obligations.” — Jennifer Nuzzo, associate professor, Johns Hopkins

What’s one thing you’ll never take for granted again?

“I won’t take traveling to my extended family for granted.” — Alicia Allen, assistant professor, University of Arizona

Will we ever go to a big, crowded, indoor party without a mask again?

“If the level of infection in the community seems substantial, you’re not going to have the parties with friends in congregant settings. If the level of infection is so low that risk is minuscule, you’re going to see back to the normal congregating together, having parties, doing that. If we want to get back to normal it gets back to my message: When the vaccine becomes available, get vaccinated.” — Dr. Fauci


Contributors: Sara Aridi, Quoctrung Bui, Abby Goodnough, David Leonhardt, Apoorva Mandavilli, Donald G. McNeil Jr., Claire Cain Miller, Yuliya Parshina-KottasRoni Caryn Rabin, Margot Sanger-Katz, Amy Schoenfeld Walker, Noah Weiland, Jeremy White Katherine J. Wu and Carl Zimmer

What People With Allergies Should Know About Covid Vaccines

Here’s What People With Allergies Should Know About Covid Vaccines

Four people so far have had allergic reactions after getting the Pfizer-BioNTech vaccine. Experts say that shouldn’t deter most people from getting a jab.

Vaccinations underway in Orange, Calif., on Wednesday.
Vaccinations underway in Orange, Calif., on Wednesday.Credit…Jenna Schoenefeld for The New York Times
Katherine J. Wu

  • Dec. 18, 2020, 12:27 p.m. ET

Allergic reactions reported in two health workers who received a dose of Pfizer’s vaccine in Alaska this week have reignited concerns that people with a history of extreme immune flare-ups might not be good candidates for the newly cleared shots.

The two incidents follow another pair of cases in Britain. Three of the four were severe enough to qualify as anaphylaxis, a severe and potentially life-threatening reaction. But all four people appear to have recovered.

Health officials on both sides of the pond are vigilantly monitoring vaccinated people to see if more cases emerge. Last week, British drug regulators recommended against the use of Pfizer’s vaccine in people who have previously had anaphylactic reactions to food, medicines or vaccines.

And on Thursday, Dr. Doran Fink, deputy director of the Food and Drug Administration’s clinical division of vaccines and related products applications, addressed the issue during a meeting about the vaccine made by Moderna that contains similar ingredients and is expected to soon receive emergency use authorization, or E.U.A., from the agency.

“We anticipate that there may be additional reports, which we will rapidly investigate,” Dr. Fink said, adding that robust surveillance systems were in place to detect these rare events.

Still, Dr. Fink said that “the totality of data at this time continue to support vaccinations under the Pfizer E.U.A., without new restrictions.”

The F.D.A., he added, would work with Pfizer to revise fact sheets and prescribing information for the vaccine so that the public would understand the risk of allergic reactions and know how to report them.

What do we know about the people who had bad reactions?

The first two confirmed cases of allergic reactions came from two health care workers in Britain. Both had a medical history of serious allergic reactions, but had not previously been known to have trouble with any of the vaccine’s ingredients. After an injection of epinephrine — the typical treatment for anaphylaxis — both recovered.

(A third British incident described as a “possible allergic reaction” was also reported and appears to have been minor.)

On Wednesday, two health workers in Alaska experienced reactions as well. One was too mild to be deemed anaphylaxis. But the other, which occurred in a middle-aged woman with no history of allergies, was serious enough to warrant hospitalization, even after she got a shot of epinephrine.

“What is happening does seem really unusual to me,” said Dr. Kimberly Blumenthal, an allergist, immunologist and drug allergy researcher at Massachusetts General Hospital. Vaccine-related allergic reactions are typically rare, occurring at a rate of about one in a million.

Dr. Blumenthal also pointed out that it was a bit bizarre to see allergic reactions clustering in just two locations: Britain and Alaska. Zeroing in on the commonalities between the two hot spots, she said, might help researchers puzzle out the source of the problem.

Do we know for sure that their reactions were caused by the vaccine?

British and U.S. agencies are investigating the causes, but no official has declared a direct link.

But Dr. Blumenthal suspects they were connected to the shots, because the reactions were immediate, occurring within minutes of injection.

“We have to think it was related because of the timing,” she said.

Nor is it known if a particular ingredient might have been the cause. Pfizer’s vaccine contains just 10 ingredients. The most important is a molecule called messenger RNA, or mRNA — genetic material that can instruct human cells to make a coronavirus protein called spike. Once manufactured, spike teaches the immune system to recognize the coronavirus so it can be fought off in the future. Messenger RNA, which is naturally found in human cells, is unlikely to pose a threat, and degrades within about a day of being injected.

The other nine ingredients are a mix of salts, fatty substances and sugars that stabilize the vaccine. None are common allergens. The only chemical with a history of causing allergic reactions is polyethylene glycol, or PEG, which helps package the mRNA into an oily sheath, protecting it as it goes into human cells.

But PEG is, generally speaking, inert and widespread. It’s found in ultrasound gel, laxatives like Miralax and injectable steroids, among other drugs and products, Dr. Blumenthal said. Despite the chemical’s ubiquity, she said, “I’ve only seen one case of a PEG allergy — it’s really, really uncommon.”

It’s still possible that something else could be causing the reactions — perhaps a factor related to how the vaccines are transported, thawed or administered, Dr. Blumenthal said.

Did the volunteers in Pfizer’s clinical trials have any bad reactions?

A small number of volunteers in Pfizer’s clinical trials experienced allergic reactions. Just one of the 18,801 participants who received the vaccine in a late-stage trial had anaphylaxis, and the incident was deemed unrelated to the vaccine, said Steven Danehy, a spokesman for Pfizer. No severe reactions were found in people who got a placebo shot.

Pfizer excluded people with a history of anaphylaxis to vaccines from its clinical trials.

What does the F.D.A. say about these reactions?

Several experts raised concerns about the allergic reactions in meetings convened to discuss both Pfizer’s and Moderna’s vaccines. The agency has advised caution, noting that health care providers should not administer the vaccine to anyone with a “known history of a severe allergic reaction” to any component of the vaccine — a standard warning for vaccines.

Should people with mild allergies wait to get vaccinated?

There’s no evidence that people with mild allergies, which are quite common, need to avoid the vaccine. Allergies are, simply put, the product of an inappropriate immune response against something harmless — pollen, peanuts, cat dander and the like. In many cases, the results of this overreaction are mild symptoms such as a runny nose, coughing or sneezing.

But allergies are specific: A reaction to one substance does not guarantee a reaction to another. On Monday, the American College of Allergy, Asthma and Immunology released guidance stating that people with common allergies “are no more likely than the general public to have an allergic reaction to the Pfizer-BioNTech Covid-19 vaccine.”

William Amarquaye, a clinical pharmacist at Brandon Regional Hospital, said he wouldn’t let his asthma or allergies stop him from taking the vaccine when it is offered to him in the next few weeks. He’s also never had trouble with other vaccines he has taken in the past.

“It should still be OK to take the vaccine,” Dr. Amarquaye said. “I’m actually excited about it.”

What about people with a history of severe allergies?

Most people in this category should be good to go, too, said Dr. Eun-Hyung Lee, an expert in allergy and immunology at Emory University.

Guidelines released by the Centers for Disease Control and Prevention identify only one group of people who might not want to get Pfizer’s vaccine: those with a known history of severe allergic reactions to an ingredient in the injection.

People with a history of anaphylaxis to any other substance, including other vaccines or injectable drugs, can still get the vaccine, but should consult their health care providers and be monitored for 30 minutes after getting their shots. Everyone else, like people with mild or no allergies, need to wait only 15 minutes before leaving the vaccination site.

“In general, the immediate reactions that require epinephrine are those that happen within the first 30 minutes,” said Dr. Merin Kuruvilla, an allergist and immunologist at Emory University.

Some people will understandably be concerned. Dr. Taison Bell, a critical care physician at UVA Health in Charlottesville, Va., said he worried about his 7-year-old son, Alain, who is severely allergic to several foods, including wheat, peanuts and cow’s milk. Alain has about two bouts of anaphylaxis each year.

It’s a bit of a relief that Alain is “later in the prioritization schema,” Dr. Bell said. By the time a vaccine is ready for him, he said, “we’ll get a better sense for how serious this is.” The family plans to discuss their situation with Alain’s doctor.

Ultimately, it’s unlikely that any of the ingredients in a coronavirus vaccine would cause Alain any issues. Alain has tolerated other vaccines, including the flu shot, in previous years, and is looking forward to his own shot at immunization to the coronavirus, said Dr. Bell, who received his first dose of Pfizer’s vaccine on Tuesday.

What about Moderna’s vaccine?

Two volunteers in Moderna’s late-stage clinical trial developed anaphylactic reactions, the company reported at the F.D.A. committee meeting on Thursday. Neither was deemed to be linked to the company’s vaccine, which also contains mRNA, because they occurred weeks or months after the participants received their shots. One of these volunteers also had a history of asthma and a shellfish allergy.

Moderna, unlike Pfizer, did not exclude people with a history of anaphylaxis from its trials.

Dr. Tal Zaks, the company’s chief medical officer, said that while Moderna’s vaccine recipe was similar to Pfizer’s, key molecular differences existed that could set the two products on different paths. He said that bad reactions to Pfizer’s vaccine did not guarantee that similar events would happen in relation to the Moderna shots.

Both vaccines do, however, include a version of PEG.

Dr. Blumenthal and others said that anyone concerned about having an allergic reaction to a vaccine should seek the advice of a health care provider.

For anyone getting the vaccine, it’s all about “balancing out the risks,” Dr. Lee, of Emory, said. Allergic reactions can be dangerous. But they are rare and treatable, and the tools to combat them should be available at all vaccination sites. The coronavirus, on the other hand, can have far graver consequences.

“When it’s my turn in line, I think weighing these odds is what I would do,” Dr. Lee said.

How New York City Vaccinated 6 Million People in Less Than a Month

The vaccination line on April 14, 1947, at the New York City Health Department.
The vaccination line on April 14, 1947, at the New York City Health Department.Credit…Arthur Brower/The New York Times

How New York City Vaccinated 6 Million People in Less Than a Month

When a single case of smallpox arrived in Manhattan in 1947, a severe outbreak was possible. A decisive civil servant made a bold decision.

The vaccination line on April 14, 1947, at the New York City Health Department.Credit…Arthur Brower/The New York Times

  • Dec. 18, 2020, 5:00 a.m. ET

On Easter weekend in 1947, New York City buzzed with an air of invincibility. The miseries of World War II were finally over, and New York, like the rest of the country, was buoyant. The future promised great things. The Polaroid Land camera had just been invented. Consumer TV sets were appearing in living rooms. The transistor radio was in the works.

What the public didn’t know was that smallpox, the scourge of civilizations, had improbably re-emerged in the city five weeks earlier.

On March 1, a 47-year-old American businessman, Eugene Le Bar, arrived in New York after a long bus ride from Mexico City. He was on his way to Maine, but he had been feeling sick and checked into a Midtown hotel with his wife. After sightseeing, he collapsed into bed, exhausted, with a headache and a pain in the back of his neck.

By March 5, Mr. Le Bar was in Bellevue Hospital with a 105-degree fever and a peculiar-looking rash on his face and hands. Three days later, he was transferred to Willard Parker, the city’s communicable disease hospital. His doctors considered several diagnoses, none definitive. Because he had a vaccination scar, they ruled out smallpox. On March 10, Mr. Le Bar was dead.

Soon, more patients at Willard Parker began exhibiting symptoms similar to Mr. Le Bar’s: first, a 22-month-old baby from the Bronx named Patricia, then a 27-year-old man from Harlem, Ismael Acosta. A 30-month-old toddler, John, followed. The doctors thought they were looking at chickenpox, but were flummoxed by the patients’ rashes, which didn’t fit the diagnosis.

The route of infection: A map from Life Magazine showing the path of Eugene Le Bar’s bus ride to New York.
The route of infection: A map from Life Magazine showing the path of Eugene Le Bar’s bus ride to New York.Credit…Life Magazine
A newspaper article clipping about the smallpox outbreak.

On April 4, the results came back from the U.S. Army Medical School Laboratory in Washington. All three were confirmed cases of smallpox, which had not been seen in New York City since before the war. Health officials began connecting the dots, and the dots led back to Eugene Le Bar, patient zero.

The city’s health commissioner, Israel Weinstein, had taken the job 10 months earlier. He’d been a child on the Lower East Side when a smallpox outbreak brought the city to its knees in the early 1900s, killing 720 New Yorkers in a two-year period. Now he was both a medical doctor and a scientist; he had earned a doctorate from New York University, along with a Ph.D. and an M.D. from Columbia.

So when he got the lab results, he knew what he was up against.

Smallpox had plagued humankind for thousands of years. According to the World Health Organization, it claimed the lives of 300 million people in the 20th century alone.

All it takes for smallpox to spread is a cough, a sneeze or a touch. After that, it’s only a matter of days before the virus triggers fever, aches, pains and nausea. A rash appears on the face and soon covers the body, sprouting into fluid-filled pustules. Three out of 10 cases are fatal. Those who survive are often left deeply scarred, blind or both.

“In the pantheon of infectious diseases, smallpox is in the top five,” said Dr. Charles DiMaggio, professor of surgery and population health at N.Y.U. Grossman School of Medicine. “It was thoroughly horrifying because it disfigured people it didn’t kill, and it killed indiscriminately.”

Thanks to a vaccine developed in the late 1700s and refined in the decades that followed, smallpox outbreaks had generally been contained.

In 1980, the World Health Organization officially declared smallpox eradicated.

The making of smallpox vaccine in 1947 at Lederle Laboratories in Pearl River, N.Y.Credit…Fritz Goro/The LIFE Picture Collection, via Getty Images

“The smallpox eradication program is absolutely considered one of the crowning achievements of global public health,” Dr. DiMaggio said. “And it’s never been duplicated. Just the very idea that a disease was eradicated — a disease that ravaged humankind for millennia — is remarkable. And the reason we were able to do that is because of vaccinations.”

In 1947, most New Yorkers had been inoculated against smallpox. They’d been told the inoculation would protect them for life — but there was no guarantee. In some cases, the vaccine didn’t take. In others, the immunity wore off. Mr. Le Bar was proof of that.

Dr. Weinstein had some tough decisions to make.

The lab results reached him on Good Friday, April 4. In two days, New Yorkers would be gathering for the city’s annual Easter Parade. If only one of them had smallpox, even among a vaccinated population, the resulting outbreak could be devastating.

“Imagine the Easter Parade, and all these people crowded together on Fifth Avenue,” said Dr. Howard Markel, director of the Center for the History of Medicine at the University of Michigan. “All of them cheering and chanting, and potentially coughing and sneezing, and you have smallpox introduced into that picture. That is a public health nightmare.”

Dr. Weinstein wasted no time. Knowing there was only one way to deal with the virus — vaccination — he took action. At 2 o’clock that day, he held a news conference, urging all city dwellers to get vaccinated immediately, even if they had been inoculated as children. Re-vaccinations were necessary, he said, in case people had lost their immunity.

It was hardly without risk. Not only could the announcement cause mass hysteria, but in 1947, vaccines were not tested the way they are today. The vaccine available at the time could trigger rare but dangerous side effects, especially in people with weakened immune systems or particular skin conditions.

According to Dr. David Oshinsky, professor of medicine at NYU Langone Health, Dr. Weinstein acted in line with the scientific knowledge of the era. He made the right move, which was to vaccinate as many people as possible.

Dr. Israel Weinstein, the New York City health commissioner, vaccinating a member of his staff, Doris Wendroff, in April 1947.Credit…Arthur Brower/The New York Times

Dr. Israel Weinstein Audio

Courtesy of the NYC Municipal Archives WNYC collection

Dr. Markel agrees. “Weinstein was doing his job as best he could,” he said. “The risk of smallpox spreading and causing disease and death was far, far greater than the tiny risk of getting encephalitis or dying of the vaccine. So, I come not to bury Weinstein, but to praise him.”

In a series of daily radio addresses, Dr. Weinstein focused on transparency and a consistent message. The vaccine, he said, was free, and there was, in his words, “absolutely no excuse for anyone to remain unprotected.” In a calm, clear voice, he promoted the rallying cry that would appear on posters throughout the city: “Be Sure. Be Safe. Get Vaccinated!”

“The first thing he did was level with the public,” Dr. Oshinsky said. “He told them that smallpox had arrived in the city, and that it was possible there was going to be a spread — and that it was an extremely communicable and dangerous disease. And he said, ‘We will provide enough vials of vaccine to effectively protect the city.’”

But the municipal stockpile contained nowhere near enough to vaccinate all of the city’s 7.8 million residents.

With the full cooperation of Mayor William O’Dwyer, Dr. Weinstein secured 250,000 units of vaccine from the naval medical supply depot in Brooklyn. He had 780,000 doses flown in from military bases in California and Missouri. He purchased an additional two million from private manufacturers, and then he ordered more.

He directed his Bureau of Laboratories to convert its bulk supplies into single-dose units, and he began a tracing program to locate and vaccinate those who had been in contact with the victims.

The lines at Morrisania Hospital in the Bronx on April 14, 1947, represented a fraction of the New Yorkers who answered a city appeal to get vaccinated against smallpox. Credit…Bettmann, via Getty Images

The vaccine rollout was remarkably swift and uncomplicated, and it’s one that almost certainly couldn’t happen today.

“In 1947, the city was able to act alone, as opposed to navigating a complicated relationship with the governor of New York and the federal government,” said Dr. Irwin Redlener, director of the Pandemic Resource and Response Initiative at Columbia University’s Earth Institute. “The city was able to say, ‘We’re going after this,’ and then make it happen.”

At first, the public’s response was lackluster. Easter Sunday turned out to be surprisingly warm and sunny — the temperature hit a record 79 degrees — and more than a million New Yorkers turned out for the parade. That weekend, only 527 people requested vaccines. But days later when news broke that Ismael Acosta’s wife, Carmen, had died from smallpox, and that three more cases had been discovered, people’s minds changed — and, as it happened, so did the weather.

New Yorkers were soon standing for hours, often in chilly rain, outside public and private hospitals, clinics and police stations, waiting to get their inoculations. For them, vaccinations were nothing new. Many had served as soldiers in World War II; they had been vaccinated against a host of viruses and saw the inoculations as a matter of course. Moreover, today’s anti-vaccination movement did not exist.

Dr. Oshinsky, who wrote the Pulitzer Prize-winning book “Polio: An American Story,” offers yet another reason. “This was the height of polio in the United States,” he said. “People had a much better sense of the impact of infectious disease. They saw it all the time, and they were rightly fearful. But they were also optimistic that medical science could conquer this. In 1947, there was tremendous faith in the medical community, unlike today.”

 In the city’s schools, 889,000 students were inoculated, like these at St. Joan of Arc Parochial School in Jackson Heights, Queens.Credit…Art Edger/NY Daily News Archive, via Getty Images

In front of news cameras, Dr. Weinstein vaccinated Mayor O’Dwyer, who had already been inoculated four times in the Army. President Harry S. Truman also got into the act. His visit to New York on April 21 was accompanied by news reports that he, too, had rolled up his sleeve.

“In today’s vernacular, O’Dwyer and Truman were influencers,” said Lisa Sherman, president of the Ad Council, the nonprofit group working on a campaign for the Covid-19 vaccines. “They could deliver important information that people wanted to hear. They were trusted messengers.”

The response was so great that the city enlisted thousands of civilian volunteers to help deliver inoculations. Armed with vials of vaccine, the volunteers, along with professional health care providers, administered as many as eight doses per minute. Making their way through every school in the city, they inoculated 889,000 students. In the first two weeks, five million New Yorkers were vaccinated against smallpox.

By mid-April, the city’s stockpile was nearly depleted. Mayor O’Dwyer convened an emergency meeting of drug company representatives, all but threatening them with public scorn if they didn’t ramp up delivery. Within 48 hours, a million more doses arrived.

In early May, 10 weeks after Eugene Le Bar stepped off a bus in Manhattan, Dr. Weinstein announced that the danger had passed.

Later that year, he summed up the case in The American Journal of Public Health. “In a period of less than a month, 6,350,000 people were vaccinated in New York City,” he wrote. “Never before had so many people been vaccinated in such a city and on such short notice.”

The finally tally was 12 infections and two deaths.

“What Dr. Weinstein did in 1947 is something we’re still studying and referring to,” Dr. Markel said. “The fact that they developed the logistics — the delivery of vaccine, the large public spaces where people could line up to get vaccines, the manpower in the form of nurses and doctors who would give the vaccine — is pretty incredible. Weinstein is to be credited.”

In the first two weeks of the 1947 outbreak, five million New Yorkers were vaccinated against smallpox.Credit…The Everett Collection

“It stands out as a remarkable achievement by any measure,” Dr. DiMaggio said. “It was a public health triumph.”

Dr. Weinstein resigned from his post in November 1947, seven months after the smallpox outbreak. He left behind a blueprint for containing an infectious disease in a large, dense city.

But this time, with the coronavirus pandemic, New York faces a logistical hurdle. Experts in infectious disease point to a hollowing out of the public health infrastructure — not just in the city, but across the country. Yet, they believe the biggest obstacle is not distribution but the public’s distrust of government, science and the media.

“We’re coming out of a train wreck of messaging,” Dr. Redlener said. “We’ve learned that politics is poison to a public health initiative, especially during a crisis. Honesty and straightforward, clear messaging are absolutely critical.”

In 1947, Dr. Weinstein was the only voice with a megaphone. He spoke and people listened.

“Back then, there was a much simpler media landscape,” Ms. Sherman said as she laid out the Ad Council’s campaign, which is due to kick off early next year. “In today’s environment, we’re dealing with a highly, highly fragmented media. We’ll be relying on micro-influencers who are the trusted voices.”

So, as the Covid-19 vaccine rollout in New York City began this past week, a major question remains: Can the city come close to what it accomplished 73 years ago?

Dr. Redlener, who serves as an adviser to Mayor Bill de Blasio on emergency response, said he believes that New York will meet the challenge again. But he added, “It’s almost inconceivable that we’re going to be able to do something similar as rapidly and as effectively.”

Weekly Health Quiz: Covid Vaccines, Winter Sports and a Cancer Breakthrough

1 of 7

Which statement about the new coronavirus vaccines is not true?

About 20 million Americans, including health care workers and residents of nursing homes, will be the first to get vaccinated

Vaccination requires two shots, three to four weeks apart

The vaccine can help protect you from getting infected with coronavirus, though it’s uncertain whether it will prevent you from spreading it to others

If you’ve already had natural Covid, it’s not safe to get vaccinated

2 of 7

In rare cases, the coronavirus vaccine has caused a severe allergic reaction, with symptoms such as a rash and shortness of breath developing about how long after getting the shot?

10 minutes

1 day

3 days

10 days

3 of 7

Mycobacterium marinum, a tuberculosis-like infection that can cause painful joint swelling, is spread through cuts in the skin from handling raw:

Pork

Fish

Poultry

Beef

4 of 7

Which of the following Winter Olympic Sports has the lowest rate of injuries?

Snowboard cross

Freestyle skiing aerials

Bobsled

Ski jumping

5 of 7

Paul Farmer, a medical anthropologist, received the $1 million Berggruen Prize for his work on:

Raising awareness of environmental cancers

Providing health care to underserved communities

Discovering the hepatitis C virus

Developing new methods of birth control

6 of 7

In recent decades, the mortality rate from falls in this age group more than doubled:

People aged 25 to 44

People aged 45 to 64

People aged 65 to 75

People over 75

7 of 7

A new scan that detects malignant cells anywhere in the body may lead to improved treatments for this cancer that kills 33,000 American men each year:

Testicular cancer

Penile cancer

Prostate cancer

Male breast cancer

Life After Covid: When Can We Start Making Plans?

When Can We Start Making Plans?

We asked Dr. Anthony S. Fauci and other experts when they thought life would start to feel more normal.

Credit…Vincent Neuberg
Tara Parker-Pope

  • Dec. 16, 2020, 5:00 a.m. ET

The United States moved one step closer to getting back to normal this week with the first Covid vaccinations of health care workers around the country. While the majority of Americans won’t get their shots until spring, the vaccine rollout is a hopeful sign of better days ahead. We asked Dr. Anthony S. Fauci, as well as several epidemiologists and health and science writers for The Times, for their predictions about the months ahead. Here’s what they had to say.

What advice do you have for families eager to celebrate the holidays with their loved ones?

“Do it by Zoom. Don’t let Junior come home and kill Grandma. Think of this like World War II — our soldiers didn’t get to fly home to eat turkey. My father was at Normandy. My mother was with the Red Cross in occupied Austria. They missed the holidays. Life went on. There were happier years later.” — Donald G. McNeil Jr., health and science reporter

Will we shake hands again?

“I’m not. I don’t know about you. I said that many, many months ago and the newspapers went wild with it. I’m sure people will get back to shaking hands. I think people will probably become more aware of personal hygiene and protecting yourself. That doesn’t mean nobody will shake hands again, nor does it mean everybody will go back to the way we did it again. Probably somewhere in between. Some people will be reluctant to shake hands. Some people will be washing hands a whole lot more than they ever did, even when Covid-19 is no longer around.” — Dr. Anthony S. Fauci

When would you personally feel comfortable returning to the office?

“When I’m vaccinated and everyone around me is.” — McNeil

Is my employer going to require me to to be vaccinated?

“Employers do have the right to compel their workers to be vaccinated once a vaccine is formally approved. Many hospital systems, for example, require annual flu shots. But employees can seek exemptions based on medical reasons or religious beliefs. In such cases, employers are supposed to provide a ‘reasonable accommodation’; with a coronavirus vaccine, a worker might be allowed to wear a mask in the office instead, or to work from home.” — Abby Goodnough, national health care correspondent

Will we ever go to a big, crowded, indoor party without a mask again?

“If the level of infection in the community seems substantial, you’re not going to have the parties with friends in congregant settings. If the level of infection is so low that risk is minuscule, you’re going to see back to the normal congregating together, having parties, doing that. If we want to get back to normal it gets back to my message: When the vaccine becomes available, get vaccinated.” — Dr. Fauci

Do we have to wait for 75 percent of the population to be vaccinated before we can travel again?

“I think traveling is going to start easing up as you get much less than that. I think it’s going to be gradual. There is no black and white, light switch on, light switch off.” — Dr. Fauci

How long will we be wearing masks?

“If you get herd immunity where there are no infections around, you wouldn’t have to wear a mask all the time. You might want to wear it if you were in a crowded situation, but you wouldn’t have to have the stringency you have now. Ultimately, I think you’re going to have to transition from wearing all the time, to wearing it under certain circumstances, to perhaps not having to wear it at all.” — Dr. Fauci

How will we know it’s safe to do normal things?

“First of all, it’s going to be expressed by the number of new cases that you see — the test positivity number. You’ve got to go as low as you can get. The best number is zero. It’s never going to be zero, but anywhere close to that is great.” — Dr. Fauci

When can we go to the movies or the theater?

“It depends on the uptake of the vaccine and the level of infection in the community. If you go to April, May, June and you really put on a full-court press and try to vaccinate everybody within a period of a few months, as you go from second to third quarter of the year, then you could likely go to movies, go to theaters, do what you want. However, it’s unlikely, given what we’re hearing about people’s desire to get vaccinated, that we’re going to have that degree of uptake. If it turns out that only 50 percent get vaccinated, then it’s going to take much, much longer to get back to the kind of normality that we’d like to see.” — Dr. Fauci

When will you eat in a restaurant?

“If more than half the population is vaccinated, I would feel a little less stressed and anxious when heading out to do errands I normally do. I might actually feel comfortable to eat in a restaurant or see friends again one day if this is possible.”— Vijaya L. Seegulam, research project manager, Boston University

When will you feel comfortable in a crowd?

“Once my family and I are vaccinated, I would change behaviors, except I can’t imagine being in a crowd or attending any crowded events until at least 80 percent of the population is vaccinated.”— Julie Bettinger, associate professor, University of British Columbia

When will restrictions start to ease up?

“I think widespread availability of vaccines will result in the further relaxation of most precautions by mid- to late summer 2021.” — Michael Webster-Clark, postdoctoral researcher, University of North Carolina at Chapel Hill

What will the new normal look like?

“The new normal will be continued masking for the next 12 to 18 months and possibly the next few years. This is a paradigm shift.” — Roberta Bruhn, epidemiology core co-director, Vitalant Research Institute

What will never return to normal?

“My relationships with people who have taken this pandemic lightly and ignored public health messages and recommendations.” — Victoria Holt, professor emeritus, University of Washington

What did you learn from pandemic life?

“Staying home with my children has taught me that life with fewer errands to run and activities to partake in is kind of nice. I think in the future we will cut down on our family obligations.” — Jennifer Nuzzo, associate professor, Johns Hopkins

What pandemic habit will you keep?

“I’m going to keep my mask, and wear it in crowds and on subways, particularly during cold and flu season. I used to get sick all the time, but I haven’t had a cold or sore throat in months. I really like not getting sick!”

What’s one thing you’ll never take for granted again?

“I won’t take traveling to my extended family for granted.” — Alicia Allen, assistant professor, University of Arizona

What has forever changed in your daily life?

“I will never again have to explain what an epidemiologist is.” — Janet Rich-Edwards, associate professor, Harvard

Contributors: Margot Sanger-Katz, Claire Cain Miller and Quoctrung Bui

Answers to Your Questions About the New Covid Vaccines in the U.S.

Answers to Your Questions About the New Covid Vaccines in the U.S.

Vaccines are rolling out to health workers now and will reach the arms of the rest of us by spring. Here’s what you need to know.

The Pfizer-BioNTech Covid vaccines are prepared to be shipped at a Pfizer plant on Dec. 13, 2020 in Portage, Michigan.
The Pfizer-BioNTech Covid vaccines are prepared to be shipped at a Pfizer plant on Dec. 13, 2020 in Portage, Michigan.Credit…Pool photo by Morry Gash
  • Dec. 14, 2020, 1:47 p.m. ET

Getting the vaccine

Why can’t everyone get the vaccine now?

There aren’t enough doses for everyone, so initially the vaccine will be rationed for those who need it most. It will take time to produce and distribute the vaccine, and then schedule two vaccinations per person, three to four weeks apart. As more vaccines get approved, things will speed up. At least 40 million doses (enough for 20 million people) should be available from Pfizer and Moderna by the end of the year, and much more will come in 2021. How many doses will your state get? Look up your state’s vaccine distribution plans here. —Abby Goodnough

Who will get the vaccine first?

Here’s the expected order for vaccinations:

  • Health care workers and people in long-term care facilities: The nation’s 21 million health care workers and three million mostly elderly people living in long-term care facilities will go first, starting in December. Initially, there won’t be enough doses to vaccinate all health care workers, so states will prioritize based on exposure risk, choosing emergency room staff, for instance, to go first. Or they may offer the vaccine to the oldest health care workers first.

  • Essential workers: The 87 million Americans who work in food and agriculture, manufacturing, law enforcement, education, transportation, corrections, emergency response and other sectors, likely will be second in line, starting early next year. States will set priorities. Arkansas, for example, has proposed including workers in its large poultry industry, while Colorado wants to include ski industry workers who live in congregate housing.

  • Adults with underlying medical conditions and people over 65. Health officials are hoping to get any remaining older adults who have not been vaccinated sometime in the first quarter. Some states might decide to vaccinate residents over 75 before some types of essential workers.

  • All other adults. Adults in the general population are at the back of the line. They could start receiving the vaccine as early as April, said Dr. Anthony S. Fauci, the nation’s top infectious disease expert, although many people likely will have to wait until at least May or June. The vaccine hasn’t been approved in children, so it may be several months, or possibly a year, before the vaccine is available for anyone under the age of 16. —Abby Goodnough, Tara Parker-Pope

How will the first doses of the vaccine get to health workers?

Hospitals and medical groups are contacting health workers to schedule vaccine appointments. FedEx and UPS will transport the vaccine throughout most of the country, and each delivery will be followed by shipments of extra dry ice a day later.

Pfizer designed special containers, with trackers and enough dry ice to keep the doses sufficiently cold for up to 10 days. Every truck carrying the containers will have a device that tracks its location, temperature, light exposure and motion. Pfizer will ship the special coolers, each containing at least 1,000 doses, directly to locations determined by each state’s governor. At first, almost all of those sites will probably be hospitals that have confirmed they can store shipments at minus 94 degrees Fahrenheit, as the Pfizer vaccine requires, or use them quickly. —Abby Goodnough

How will the vaccine get to nursing homes?

The pharmacy chains CVS and Walgreens have contracts with the federal government to send teams of pharmacists and support staff into thousands of long-term care facilities in the coming weeks to vaccinate all willing residents and staff members. CVS and Walgreens are both planning to administer their first vaccinations on Dec. 21.

More than 40,000 facilities have chosen to work with CVS. Nearly 35,000 picked Walgreens. Each U.S. state has already picked, or will soon pick, either the Pfizer or the Moderna vaccine for all of its long-term care facilities that will be working with the pharmacies. —Rebecca Robbins, Abby Goodnough

How will the rest of us get vaccinated?

It’s likely that when the general public starts getting vaccinated in April, shots will be scheduled through doctor’s offices, CVS, Walgreens and other pharmacies — the same way people get flu shots. However, final plans will depend on what other vaccines besides Pfizer’s and Moderna’s have been approved. —Abby Goodnough, Rebecca Robbins

Can I choose which vaccine I get?

This depends on a number of factors, including the supply in your area at the time you’re vaccinated and whether certain vaccines are found to be more effective in certain populations, such as older adults. At first, the only choice will be Pfizer’s vaccine, though Moderna’s could become available within weeks. —Abby Goodnough

How long will it take to work?

You won’t get the full protection from the Pfizer-BioNTech vaccine until about a week after the second dose, based on clinical trial data. The researchers found that the vaccine’s protection started to emerge about ten days after the first dose, but it only reached 52 percent efficacy, according to a report in the New England Journal of Medicine. A week after the second dose, the efficacy rose to 95 percent. Read more here. —Carl Zimmer, Noah Weiland

Safety and side effects

Will it hurt? What are the side effects?

The injection into your arm won’t feel different than any other vaccine, but the rate of short-lived side effects does appear higher than a flu shot. Tens of thousands of people have already received the vaccines, and none of them have reported any serious health problems. The side effects, which can resemble the symptoms of Covid-19, last about a day and appear more likely after the second dose. Early reports from vaccine trials suggest some people might need to take a day off from work because they feel lousy after receiving the second dose. In the Pfizer study, about half developed fatigue. Other side effects occurred in at least 25 to 33 percent of patients, sometimes more, including headaches, chills and muscle pain.

While these experiences aren’t pleasant, they are a good sign that your own immune system is mounting a potent response to the vaccine that will provide long-lasting immunity. —Abby Goodnough, Carl Zimmer

How do I know it’s safe?

Each company’s application to the F.D.A. includes two months of follow-up safety data from Phase 3 of clinical trials conducted by universities and other independent bodies. In that phase, tens of thousands of volunteers got a vaccine and waited to see if they became infected, compared with others who received a placebo. By September, Pfizer’s trial had 44,000 participants; no serious safety concerns have been reported. — Abby Goodnough

If I have allergies, should I be concerned?

People with severe allergies who have experienced anaphylaxis in the past should talk to their doctors about how to safely get the vaccine and what precautions to take. Although severe reactions to vaccines are rare, two health care workers had anaphylaxis after receiving the vaccine on the first day it became available in Britain. Both workers, who had a history of severe reactions, were treated and have recovered. (Anaphylaxis can be life-threatening, with impaired breathing and drops in blood pressure that usually occur within minutes or even seconds after exposure to a food, medicine or substance like latex.) For now, British authorities have said the vaccine should not be given to anyone who has ever had an anaphylactic reaction, but U.S. health experts have said such warnings are premature because severe reactions can be treated or prevented with medications. Because of the British cases, the F.D.A. said it would require Pfizer to increase its monitoring for anaphylaxis and submit data on it once the vaccine comes into use. Fewer than one in a million recipients of other vaccines a year in the U.S. have an anaphylactic reaction, said Dr. Paul Offit, a vaccine expert at Children’s Hospital of Philadelphia.

Among those who participated in the Pfizer trials, a very small number of people had allergic reactions. A document published by the F.D.A. said that 0.63 percent of participants who received the vaccine reported potential allergic reactions, compared to 0.51 percent of people who received a placebo. In Pfizer’s late-stage clinical trial, one of the 18,801 participants who received the vaccine had an anaphylactic reaction, according to safety data published by the F.D.A. on Tuesday. None in the placebo group did. Read more here. — Denise Grady

What about my situation? Answers about different types of patients.

I had Covid-19 already. Do I need the vaccine?

It’s safe, and probably even beneficial, for anyone who has had Covid to get the vaccine at some point, experts said. Although people who have contracted the virus do have immunity, it is too soon to know how long it lasts. So for now, it makes sense for them to get the shot. The question is when. Some members of the C.D.C. advisory committee have suggested people who have had Covid in the past 90 days should be toward the back of the line.Read more here. —Abby Goodnough, Apoorva Mandavilli

Will it work on older people?

All the evidence we have so far suggests that the answer is yes. The clinical trials for the two leading vaccines have shown that they work about the same in older people as younger people. As the vaccines get distributed, the vaccine makers and the C.D.C. will continue to monitor the effectiveness of the vaccine in people 65 and older who, because of age-related changes in their immune systems, often don’t respond as well to vaccination as younger people do. But just as certain flu vaccines have been developed to evoke a stronger immune response in older people, it’s possible that one of the new vaccines could emerge as a better option for this age group. It’s just far too soon to know. —Carl Zimmer

I’m young and at low risk. Why not take my chances with Covid-19 rather than get a vaccine?

Covid-19 is by far the more dangerous option. Although people who are older, obese or have other health problems are at highest risk for complications from Covid-19, younger people can become severely ill, too. In a study of more than 3,000 people ages 18 to 34 who were hospitalized for Covid, 20 percent required intensive care and 3 percent died.

And as many as one in three people who recover from Covid have chronic complaints, including exhaustion, a racing heart and worse for months afterward. Covid vaccines, in contrast, carry little known risk. Read more here. —Apoorva Mandavilli

Vaccinating pregnant women and children

What about women who are pregnant or breastfeeding?

Pregnant and breastfeeding women should consult with their obstetricians and pediatricians about whether to get the vaccine. The Pfizer vaccine has not been tested in pregnant women or in those who were breastfeeding, and federal health officials have not issued any specific guidance, other than allowing these women to be vaccinated if they choose. (The American College of Obstetricians and Gynecologists issued practice guidelines to help women and their doctors talk about vaccination.)

In the initial rollout, it will be mostly pregnant health care workers who must weigh the benefits and possible risks. By the time the vaccine is available to pregnant essential workers or to women in the general population, there should be a lot more data available.

Some experts said the virus itself poses greater risks to pregnant women than the new vaccine. Since the 1960s, pregnant women have been urged to receive vaccines against influenza and other diseases. These women are generally cautioned against live vaccines, which contain weakened pathogens — but the Pfizer vaccine does not contain live virus. Read more here.Apoorva Mandavilli

Does the vaccine affect fertility or miscarriage risk?

A false claim has been circulating online that the new vaccine will threaten women’s fertility by harming the placenta. Here’s why it’s not true.

The claim stems from the fact that the vaccines from Pfizer and Moderna cause our immune systems to make antibodies to something called a “spike” protein on the coronavirus. The false warnings about fertility are based on the claim that these antibodies could also attack a similar protein that is made in the placenta during pregnancy, called syncytin. In reality, the spike protein and syncytin are similar only in one very small region, and there’s no reason to believe antibodies that can grab onto spike proteins would lock onto syncytin.

What’s more, the human body generates its own supply of spike antibodies when it fights off the coronavirus, and there’s no sign that these antibodies attack the placenta. If they did, you’d expect that women who got Covid-19 would suffer miscarriages. But a number of studies show that Covid-19 does not trigger miscarriages. Read more here. —Carl Zimmer

When will vaccines be available for children?

So far, no coronavirus vaccine has been approved for children. New vaccines are typically tested on adults before researchers launch trials on children, and coronavirus vaccine developers are following this protocol. In September, Pfizer and BioNTech began studying their vaccine on children as young as 12. Moderna followed suit in December. If these trials yield good results, the companies will recruit younger children. The FDA will then have to review these results before the vaccines can get emergency authorization. Read more here.—Carl Zimmer

Why weren’t children included in the early studies?

Vaccines are typically tested on adults first in the interest of safety. But once a vaccine is shown to be safe and effective in adults, researchers have to run more trials on children to adjust the dosage for their bodies. Another factor in the wait for a vaccine for children is that they are far less likely to die from Covid-19 than adults are. The Centers for Disease Control and Prevention issued a report in September which concluded that, of more than 190,000 people who died in the United States with Covid-19, only 121 were under the age of 21. —Carl Zimmer and Katie Thomas

Life after vaccination

What if I forget to take the second dose on time?

Both the vaccines from Pfizer-BioNTech and from Moderna have two doses, with the booster shot coming a few weeks after the first. Pfizer-BioNTech’s second dose comes three weeks after the first, and Moderna’s comes four weeks later. The second dose provides a potent boost that gives people strong, long-lasting immunity.

If for some reason you fail to get the second shot precisely three weeks after the first, you don’t have to start all over again with another two-dose regimen. “The second dose can be picked up at any time after the first. No need to start the series over,” said Dr. Paul Offit, a professor at the University of Pennsylvania and a member of the F.D.A.’s vaccine advisory panel.

And while the two leading vaccines include a second dose, some future vaccine candidates may only require one dose. Johnson & Johnson, for example, is expecting data in January that will show whether its experimental vaccine works after a single dose. In case it doesn’t, the company has also started a separate trial using two doses. —Carl Zimmer, Tara Parker-Pope

If I’ve been vaccinated, will I still need to wear a mask?

Yes, but not forever. Here’s why. The coronavirus vaccines are injected deep into the muscles and stimulate the immune system to produce antibodies. This appears to be enough protection to keep the vaccinated person from getting ill. But what’s not clear is whether it’s possible for the virus to bloom in the nose — and be sneezed or breathed out to infect others — even as antibodies elsewhere in the body have mobilized to prevent the vaccinated person from getting sick.

The vaccine clinical trials were designed to determine whether vaccinated people are protected from illness — not to find out whether they could still spread the coronavirus. Based on studies of flu vaccine and even patients infected with Covid-19, researchers have reason to be hopeful that vaccinated people won’t spread the virus, but more research is needed. In the meantime, everyone — even vaccinated people — will need to think of themselves as possible silent spreaders and keep wearing a mask. Read more here. —Apoorva Mandavilli

Will my employer require vaccinations?

Employers do have the right to compel their workers to be vaccinated once a vaccine is formally approved. Many hospital systems, for example, require annual flu shots. But employees can seek exemptions based on medical reasons or religious beliefs. In such cases, employers are supposed to provide a “reasonable accommodation” — with a coronavirus vaccine, for example, a worker might be allowed to work if they wear a mask, or to work from home. —Abby Goodnough

How will we know when things are getting better?

The test positivity rate in your community will be an indicator of how things are going. This number is the percentage of overall tests given in a community that come back positive. The lower the number, the fewer new cases and the less likely you are to cross paths with someone who has the virus. “The best number is zero,” Dr. Fauci said. “It’s never going to be zero, but anywhere close to that is great.” —Tara Parker-Pope

When can we start safely doing normal things, like going to the movies or the theater?

Public health officials estimate that 70 to 75 percent of the population needs to be vaccinated before people can start moving freely in society again. If things go well, life could get a lot better by late spring and early summer. “It depends on the uptake of the vaccine and the level of infection in the community,” Dr. Fauci said.

Given the surveys so far showing significant public reluctance to get vaccinated, however, it may take awhile to see widespread community protection, he said: “If it turns out that only 50 percent get vaccinated, then it’s going to take much, much longer to get back to the kind of normality that we’d like to see.” —Tara Parker-Pope

Will these vaccines put a dent in the epidemic?

The coronavirus vaccines will be much less effective at preventing death and illness in 2021 if they are introduced into a population where the virus is raging — as is now the case in the U.S. A vaccine that’s 95 percent effective, as Moderna’s and Pfizer’s versions appear to be, is a powerful fire hose. But the size of a fire is still a bigger determinant of how much destruction occurs.

According to the authors of a paper in the journal Health Affairs, at the current level of infection in the U.S. (about 200,000 confirmed new infections per day), a vaccine that is 95 percent effective — distributed at the expected pace — would still not be enough to end the terrible toll of the virus in the six months after it was introduced. Almost 10 million or so Americans would still contract the virus, and more than 160,000 would die.

Measures that reduce the virus’s spread — like mask-wearing, social distancing and rapid-result testing — can still have profound effects. Public health officials hope that people will continue to take these precautions at least until the country reaches a vaccination rate of 70 to 75 percent. —David Leonhardt

Will I be required to provide proof of vaccination to travel?

In the coming weeks, major airlines including United, JetBlue and Lufthansa plan to introduce a health passport app, called CommonPass, that aims to verify passengers’ coronavirus test results — and perhaps soon, vaccinations. CommonPass notifies users of local travel rules — like having to provide proof of a negative virus test — and then aims to check that they have met them.

Although no plans are in place yet to require proof of vaccination for travel or other activities, electronic vaccination credentials could have a profound effect on efforts to control the virus and restore the economy. They could prompt more employers and college campuses to reopen. And developers say they may also give some consumers peace of mind by creating an easy way for movie theaters, cruise ships and sports arenas to admit only those with documented virus vaccinations. Read the full story. —Natasha Singer

How long will the vaccine last? Will I need another one next year?

That is to be determined. It’s possible that coronavirus vaccinations will become an annual event, just like the flu shot. Or it may be that the benefits of the vaccine last longer than a year. We have to wait to see how durable the protection from the vaccines is. Immunity from coronavirus infections appears to last for months, at least, so that may be a hint about vaccines. —Carl Zimmer

How the different vaccines work

How do these new genetic vaccines work?

The Pfizer-BioNTech and Moderna vaccines use a genetic molecule to prime the immune system. That molecule, known as mRNA, is packaged in an oily bubble that can fuse to a cell, allowing the molecule to slip in. The cell uses the mRNA to make proteins from the coronavirus, which can stimulate the immune system. While the immune protection from these vaccines may last for months or perhaps even years, their mRNA does not — it is destroyed by our cells within days. Although these are described as “genetic” vaccines, the vaccines don’t alter your genes in any way. —Carl Zimmer

What do the vaccine developers mean when they say their vaccines are 95 percent effective?

Vaccine developers test their vaccines in clinical trials. The fundamental logic behind these trials was worked out by statisticians over a century ago. Researchers vaccinate some people and give a placebo to others. They then wait for participants to get sick and look at how many of the illnesses came from each group.

In the case of Pfizer, for example, the company recruited 43,661 volunteers and waited for 170 people to come down with symptoms of Covid-19 and then get a positive test. Among those who got sick, 162 had received a placebo shot, and just eight had received the real vaccine. This result shows that receiving a vaccine dramatically lowered the chances of getting Covid-19 compared to receiving a placebo.

The difference is expressed as efficacy: the Pfizer-BioNTech vaccine has an efficacy rate of 95 percent. (If there were no difference between the vaccine and placebo groups, the efficacy would be zero. If none of the sick people had been vaccinated, the efficacy rate would have been 100 percent.) A vaccine’s efficacy rate and effectiveness rate are different: Efficacy is a measurement made within the strict confines of a clinical trial, whereas effectiveness refers to how a vaccine works in the real world. No one knows yet the true effectiveness of these new vaccines. —Carl Zimmer

Was the Pfizer vaccine part of the government’s Operation Warp Speed?

Pfizer did not accept federal funding to help develop or manufacture the vaccine, unlike front-runners Moderna and AstraZeneca. Pfizer did get a $1.95 billion deal with the government to deliver 100 million doses of the vaccine. The arrangement is an advance-purchase agreement, meaning that the company won’t get paid until they deliver the vaccines. Read more here. —Carl Zimmer and Katie Thomas

What does the rollout of the Pfizer vaccine mean for the other vaccines in the race?

Researchers were heartened by the strong results of the vaccine developed by Pfizer and BioNTech. “It gives us more hope that other vaccines are going to be effective too,” said Akiko Iwasaki of Yale University.

The Moderna vaccine, which is next in line for approval, has an efficacy rate of 94.5 percent, essentially the same as the Pfizer-BioNTech vaccine. A vaccine from AstraZeneca and the University of Oxford has shown confusing trial results, with efficacy rates between 60 and 90 percent, depending on the strength of the doses that volunteers received. And the French company Sanofi had a major disappointment in its early clinical trials, finding that its vaccine couldn’t provoke an immune response in people over 55. The company is now reformulating its vaccine to start new trials. —Carl Zimmer and Katie Thomas

Reporting contributed by:

Abby Goodnough, Carl Zimmer, Rebecca Robbins, Apoorva Mandavilli, Denise Grady Katie Thomas, Tara Parker-Pope, Noah Weiland, Natasha Singer, David Leonhardt, Roni Caryn Rabin, Julie Bosman, Reed Abelson and Richard Pérez-Peña

Fears of a ‘Twindemic’ Recede as Flu Lies Low

Fears of a ‘Twindemic’ Recede as Flu Lies Low

Despite early worries, flu patients are not competing with Covid-19 patients for ventilators, and the threat of dueling outbreaks may be waning.

A free flu shot administered at Comerica Park in Detroit, Mich., last month.
A free flu shot administered at Comerica Park in Detroit, Mich., last month.Credit…Seth Herald/Agence France-Presse — Getty Images
Donald G. McNeil Jr.

  • Dec. 13, 2020, 5:00 a.m. ET

Despite the horrifying surge of Covid-19 cases and deaths in the United States right now, one bit of good news is emerging this winter: It looks unlikely that the country will endure a “twindemic” of both flu and the coronavirus at the same time.

That comes as a profound relief to public health officials who predicted as far back as April that thousands of flu victims with pneumonia could pour into hospitals this winter, competing with equally desperate Covid-19 pneumonia victims for scarce ventilators.

“Overall flu activity is low, and lower than we usually see at this time of year,” said Dr. Daniel B. Jernigan, director of the influenza division of the Centers for Disease Control and Prevention. “I don’t think we can definitively say there will be no twindemic; I’ve been working with flu for a long time, and I’ve been burned. But flu is atypically low.”

Since September, the C.D.C. “FluView” — its weekly report on influenza surveillance — has shown all 50 states in shades of green and chartreuse, indicating “minimal” or “low” flu activity. Normally by December, at least some states are painted in oranges and reds for “moderate” and “high.”

(For one puzzling week in November, Iowa stood out in dark burgundy, indicating “very high” flu levels. But that turned out to be a reporting error, Dr. Jernigan said.)

Of 232,452 swabs from across the country that have been tested for flu, only 496, or 0.2 percent, have come up positive.

That has buoyed the spirits of flu experts.

Dr. William Schaffner, medical director for the National Foundation for Infectious Diseases, which promotes flu shots, said he was recently on a telephone discussion with other preventive medicine specialists. “Everybody was in quiet awe about how low flu is,” he said. “Somebody said: ‘Shh, don’t talk about it. The virus will hear us.’”

Flu numbers are likely to remain low for many more weeks, predicted Kinsa Health, a company that uses cellphone-connected thermometers and historical databases to forecast flu trends.

“Going forward, we don’t expect influenza-like illness to go high,” said Inder Singh, Kinsa’s founder and chief executive. “It looks like the twindemic isn’t going to happen.”

7% of population sick with flu

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7% of population sick with flu

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7% of population sick with flu

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By The New York Times | Source: Kinsa

A combination of factors is responsible for the remarkably quiet flu season, experts said.

In the Southern Hemisphere, where winter stretches from June through August, widespread mask-wearing, rigorous lockdowns and other precautions against Covid-19 transmission drove flu down to record-low levels. Southern Hemisphere countries help “reseed” influenza viruses in the Northern Hemisphere each year, Dr. Jernigan said.

Also, to keep Covid-19 out, New Zealand and Australia have closed their borders either to all noncitizens or to Americans, so there has been very little air traffic from those Southern Hemisphere countries.

In the United States, the cancellation of large indoor gatherings, closings of schools and use of masks to prevent coronavirus transmission have also driven down levels of all respiratory diseases, including influenza.

In addition, Dr. Jernigan said, a “phenomenal number” of flu shots were manufactured and shipped to pharmacies, hospitals and doctors’ office in August, a month earlier than usual.

As of late November, 188 million doses had been shipped; the old record was 175 million doses shipped last year. Spot shortages were quickly reported in some cities, so experts assumed that large numbers of Americans took them.

However, there is not yet enough data to confirm that assumption. According to a preliminary tally released Dec. 9, about 70 million adults had received the shots through pharmacies or doctors’ offices as of mid-November, compared with 58 million last year.

Although that appears to be a substantial increase, the C.D.C. does not know how many Americans who normally get their flu shots at work were unable to do so this year because of stay-at-home orders, said Dr. Ram Koppaka, the agency’s associate director for adult immunization. There was a big increase in flu shots delivered by pharmacies, and that may represent people who normally would have received the shots at work.

“The best we can say is that it appears that we are now about where we were last year,” Dr. Koppaka said.

Given that vaccines were available early, he added: “I’m disappointed that it’s not better than it is. We need to keep telling people that it’s not too late to get a flu shot.”

Normally, about 80 percent of all adults who get flu shots have had them by the end of November. But about nine million doses of vaccines that were meant for uninsured adults, and which the federal government purchased this year out of fear of a “twindemic,” are still being delivered, Dr. Koppaka said.

The finally tally of how many shots were taken will not be available until summer, after the flu season is over, he said.

Nonetheless, even the preliminary data showed disturbing trends in two important target groups: pregnant women and children. Only 54 percent of pregnant women have received flu vaccine this year, compared with 58 percent by this time last year. And, although about 48 percent of all children got flu shots both last year and this year, the percentage of Black children who got them dropped substantially this year, by 11 percentage points.

Dr. Koppaka said he could not yet account for those drops in coverage. Pregnant women might have been afraid to go to doctors or pharmacies for fear of getting Covid-19, and many Black children might have been missed because public schools that offer vaccines were closed — but that was just speculation, he emphasized.

Although Dr. Koppaka strongly encouraged unvaccinated Americans to get flu shots, the threat of a two-headed pandemic monster appears to be fading.

Because of the coronavirus pandemic, the C.D.C. is not currently posting forecasts on its FluSight page, where it predicts the future course of the flu season.

Kinsa Health, by contrast, is predicting that flu will stay at historic lows through February, when the season typically peaks. The company has a record of accurately predicting flu seasons several weeks ahead of the C.D.C.

C.D.C. surveillance data is based on weekly reports from doctors’ offices and hospitals noting the percentage of patient visits that are for flu symptoms. Because there are delays in reporting, sometimes for weeks, there is a lag between the time a flu arrives in a county and the agency’s confirmation that it is there.

Also, people who catch flu but never see a doctor are not captured in the C.D.C.’s surveillance net. People avoid doctors for many reasons, including a lack of insurance or because, this year, they are afraid of catching the coronavirus.

Kinsa receives about 100,000 readings each day from about two million thermometers connected to smartphones; the company claims it can detect local fever spikes down to the ZIP code level.

Both Covid-19 and flu can drive up the number of reported fevers, but flu outbreaks can be distinguished from Covid ones, Mr. Singh said.

The company has access to decades of historical flu data from 600 cities across the country, and there are patterns to how flu typically spreads in each city based on climate and population density, said Samuel D. Chamberlain, the company’s chief data scientist.

Also, because everyone is susceptible to the new coronavirus, Covid fevers surge and spread much faster across ZIP codes than do those caused by colds and flu, Mr. Singh said.

Moreover, users are asked to enter all their symptoms in the Kinsa app. Loss of smell and taste is a common Covid-19 symptom. Making things even simpler, the app asks users if they have had a positive coronavirus or flu test.

Currently, flu is at less than half its typical level for early December, Mr. Singh said. By February, when cases typically shoot to a sharp peak, its numbers should be down to about one-quarter of a typical seasonal apex, he predicted.

“In theory, the flu virus could be taking a year off,” said Dr. Arthur Reingold, head of epidemiology at the School of Public Health of the University of California, Berkeley.

He recently asked a friend who was treating Covid-19 cases at the University of California, San Francisco, hospital how many flu cases she had seen this year.

“The answer was zero,” he said. “That’s a relief, and certainly a relief to my friends who do clinical work.”

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Pregnant and Breastfeeding Women May Opt to Receive the Vaccine

Pregnant and Breastfeeding Women May Opt to Receive the Vaccine

Although no coronavirus vaccine has been studied in these women, many scientists believe the benefits will outweigh any potential risks.

With vaccines in short supply, the F.D.A.’s decision most immediately affects the estimated 330,000 pregnant and breastfeeding health care workers in the United States.
With vaccines in short supply, the F.D.A.’s decision most immediately affects the estimated 330,000 pregnant and breastfeeding health care workers in the United States.Credit…Callaghan O’Hare/Reuters
Apoorva Mandavilli

  • Dec. 11, 2020, 11:14 p.m. ET

In its emergency authorization of the Pfizer-BioNTech vaccine on Friday night, the Food and Drug Administration took an unexpected step, leaving open the possibility that pregnant and breastfeeding women may opt for immunization against the coronavirus.

The agency authorized the vaccine for anyone 16 and older, and asked Pfizer to file regular reports on the safety of the vaccine, including its use in pregnant women.

There had been no guarantee that the agency would take this route. The vaccine was not tested in pregnant women or in those who were breastfeeding. Regulators in the United Kingdom recommended against these women receiving the shots even while acknowledging that the evidence so far “raises no concerns for safety in pregnancy.”

The Centers for Disease Control and Prevention has not yet endorsed the vaccine for pregnant women, but an advisory committee to the agency is expected to meet this weekend to make further recommendations.

Some experts said the virus itself poses greater risks to pregnant women than the new vaccine, and noted that vaccines have been given to pregnant women for decades and have been overwhelmingly safe.

“This is a really huge step forward in recognizing women’s autonomy to make decisions about their own health care,” said Dr. Emily Miller, an obstetrician at Northwestern University and a member of the Covid-19 task force of the Society for Maternal and Fetal Medicine.

With the first doses of the vaccine reserved for health care workers and residents of long-term care facilities, the F.D.A.’s authorization most immediately affects the estimated 330,000 pregnant and breastfeeding health care workers in the United States.

“I am incredibly supportive of the F.D.A.’s decision to leave the door open to Covid vaccination for pregnant and lactating workers,” said Ruth Faden, a bioethicist at Johns Hopkins University in Baltimore.

Some health care workers are at high risk of Covid-19, either because their jobs bring them into intense contact with the virus — for example, cleaning the rooms of sick patients — or because they live in low-income and multigenerational homes, Dr. Faden said.

“We have to be able to give women the opportunity to think through this for themselves with whoever it is providing obstetrical care to them,” she said.

Health care organizations should also help their employees weigh the risks, and accommodate women who do not feel comfortable working on the front lines, she added.

None of the vaccine clinical trials have so far included pregnant or lactating women, nor even women who are planning to get pregnant; some trials are expected to begin in January.

Still, the American College of Obstetrics and Gynecology, the S.M.F.M. and other organizations have been calling on the F.D.A. to allow pregnant and lactating people access to the vaccine.

At a meeting on Thursday to review Pfizer’s data for an emergency use authorization, Dr. Doran Fink, the F.D.A.’s deputy director for vaccine development, signaled that the agency was open to the idea.

“We really have no data to speak to risks specific to the pregnant women or the fetus, but also no data that would warrant a contraindication to use in pregnancy at this time,” Dr. Fink said. “Under the E.U.A., they would be then free to make their own decision in conjunction with their health care provider.”

The E.U.A. did not endorse the vaccine for pregnant or breastfeeding women, other than to note that Pfizer should collect long-term data on how the vaccine performs in pregnant women.

Since the 1960s, pregnant women have been urged to receive vaccines against influenza and other diseases. These women are generally cautioned against live vaccines, which contain weakened pathogens.

Even so, the benefits of live vaccines outweigh the risks in some situations, said Dr. Denise Jamieson, an obstetrician at Emory University in Atlanta and a member of A.C.O.G.’s committee on Covid vaccines.

“We have a long track record of giving pregnant women vaccinations, and nearly all vaccinations are very safe,” Dr. Jamieson said.

Dr. Jamieson said she was “disappointed that F.D.A. was not more explicit” but encouraged that “there is no explicit contraindication regarding pregnancy, which is good.”

Health care providers should be prepared to counsel pregnant patients on the decision to be immunized, based on the patients’ potential exposures and underlying conditions like diabetes and obesity, Dr. Jamieson added.

“A woman who can stay home, who doesn’t have any other children and no one in the household is working, is very different than an essential worker who needs to go out every day and be around other people,” she said.

Women who are contemplating pregnancy should get both vaccine doses before trying to get pregnant, she added.

In the initial rollout, it will be mostly pregnant health care workers who must weigh the benefits and possible risks. By the time the vaccine is available to pregnant essential workers or to women in the general population, there should be a lot more data available, the experts said.

“The big question we don’t know quite yet is if it actually crosses the placenta,” said Dr. Geeta Swamy, an obstetrician at Duke University in Durham, N.C., and a member of A.C.O.G.’s Covid vaccine group, referring to the vaccine. “To be honest, what would be the most reassuring would be to see some of the animal data.”

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So-called D.A.R.T. — developmental and reproductive toxicity — studies are conducted in animals to assess a vaccine’s possible effects on a fetus. These data are typically required for licensing a vaccine, but not for an E.U.A.

Animal studies would ideally have been conducted as soon as safety data on the vaccines were available and before companies started large trials, Dr. Faden, the bioethicist, said. But at the F.D.A. meeting on Thursday, officials at Pfizer hinted that the animal data would be available by the end of the year.

(Moderna did not respond to queries about its timeline for animal studies, and it was unclear whether AstraZeneca and Johnson & Johnson had begun theirs.)

“The vaccines that are behind — if they haven’t started their D.A.R.T. studies, they should start them yesterday,” Dr. Faden said.

The experts were particularly enthusiastic about the prospect that breastfeeding women might get the vaccine. “The biologic plausibility to there being some risk of harm to an infant from breastfeeding is extremely, extremely low,” Dr. Swamy said.

In the time it would take an antigen — the essential ingredient in the new vaccine — injected into a woman’s arm to travel through her bloodstream and into breast milk, the antigen would disintegrate.

“There’s not a good reason even to think that vaccinating children is unsafe,” Dr. Swamy added. “To be honest, the reason we don’t have pediatric studies yet is because they’re trying to figure out the right dosage.”

Some women breastfeed for years and, particularly in low- and middle-income countries, not being able to do so may have devastating consequences for babies, experts said.

“I would applaud the fact that the F.D.A. has recognized that in the absence of data and meaning in either direction, decisions should be made between patients and their providers,” Dr. Swamy said. “We’re talking about women who are adult individuals, right?”

The Elderly vs. Essential Workers: Who Should Get the Coronavirus Vaccine First?

The Elderly vs. Essential Workers: Who Should Get the Coronavirus Vaccine First?

The C.D.C. will soon decide which group to recommend next, and the debate over the trade-offs is growing heated. Ultimately, states will decide whom to include.

The Department of Homeland Security’s list of essential workers is long and varied, including jobs such as tugboat operators and these grocery store clerks in Brooklyn.
The Department of Homeland Security’s list of essential workers is long and varied, including jobs such as tugboat operators and these grocery store clerks in Brooklyn.Credit…Juan Arredondo for The New York Times
  • Dec. 5, 2020, 10:41 a.m. ET

With the coronavirus pandemic surging and initial vaccine supplies limited, the United States faces a hard choice: Should the country’s immunization program focus in the early months on the elderly and people with serious medical conditions, who are dying of the virus at the highest rates, or on essential workers, an expansive category encompassing Americans who have borne the greatest risk of infection?

Health care workers and the frailest of the elderly — residents of long-term-care facilities — will almost certainly get the first shots, under guidelines the Centers for Disease Control and Prevention issued on Thursday. But with vaccination expected to start this month, the debate among federal and state health officials about who goes next, and lobbying from outside groups to be included, is growing more urgent.

It’s a question increasingly guided by concerns over the inequities laid bare by the pandemic, from disproportionately high rates of infection and death among poor people and people of color to disparate access to testing, child care and technology for online schooling.

“It’s damnable that we are even being placed in this position that we have to make these choices,” said the Rev. William J. Barber II, a co-chairman of the Poor People’s Campaign, a national coalition that calls attention to the challenges of the working poor. “But if we have to make the choice, we cannot once again leave poor and low-wealth essential workers to be last.”

Ultimately, the choice comes down to whether preventing death or curbing the spread of the virus and returning to some semblance of normalcy is the highest priority. “If your goal is to maximize the preservation of human life, then you would bias the vaccine toward older Americans,” Dr. Scott Gottlieb, the former Food and Drug Administration commissioner, said recently. “If your goal is to reduce the rate of infection, then you would prioritize essential workers. So it depends what impact you’re trying to achieve.”

The trade-off between the two is muddied by the fact that the definition of “essential workers” used by the C.D.C. comprises nearly 70 percent of the American work force, sweeping in not just grocery store clerks and emergency responders, but tugboat operators, exterminators and nuclear energy workers. Some labor economists and public health officials consider the category overbroad and say it should be narrowed to only those who interact in person with the public.

Essential and Frontline Occupations

About 70 percent of workers in the U.S. have jobs that are considered essential. A subset are considered “frontline” workers, meaning their jobs cannot be performed from home. Hover or tap to see each job.

Essential

Frontline

By Matthew Conlen·Note: States may have differing definitions of essential workers. | Sources: Labor Market Information Institute, Council for Community and Economic Research, National Bureau of Economic Research, U.S. Bureau of Labor Statistics, Cybersecurity and Infrastructure Security Agency

An independent committee of medical experts that advises the C.D.C. on immunization practices will soon vote on whom to recommend for the second phase of vaccination — “Phase 1b.” In a meeting last month, all voting members of the committee indicated support for putting essential workers ahead of people 65 and older and those with high-risk health conditions.

Historically, the committee relied on scientific evidence to inform its decisions. But now the members are weighing social justice concerns as well, noted Lisa A. Prosser, a professor of health policy and decision sciences at the University of Michigan.

“To me the issue of ethics is very significant, very important for this country,” Dr. Peter Szilagyi, a committee member and a pediatrics professor at the University of California, Los Angeles, said at the time, “and clearly favors the essential worker group because of the high proportion of minority, low-income and low-education workers among essential workers.”

That position runs counter to frameworks proposed by the World Health Organization, the National Academies of Sciences, Engineering, and Medicine, and many countries, which say that reducing deaths should be the unequivocal priority and that older and sicker people should thus go before the workers, a view shared by many in public health and medicine.

Dr. Robert Redfield, the C.D.C. director and the nation’s top public health official, reminded the advisory committee of the importance of older people, saying in a statement on Thursday that he looked forward to “future recommendations that, based on vaccine availability, demonstrate that we as a nation also prioritize the elderly.”

Once the committee votes, Dr. Redfield will decide whether to accept its recommendations as the official guidance of the agency. Only rarely does a C.D.C. director reject a recommendation from the committee, whose 14 members are selected by the Health and Human Services secretary, serve four-and-a-half-year terms and have never confronted a task as high in profile as this one.

But ultimately, the decision will be up to governors and state and local health officials. They are not required to follow C.D.C. guidelines, though historically they have done so.

Defining ‘essential’

The drive-through window at a fast food restaurant in Albuquerque. Food service workers have high rates of infection from the coronavirus.
The drive-through window at a fast food restaurant in Albuquerque. Food service workers have high rates of infection from the coronavirus.Credit…Adria Malcolm for The New York Times

There are about 90 million essential workers nationwide, as defined by a division of the Department of Homeland Security that compiled a roster of jobs that help maintain critical infrastructure during a pandemic. That list is long, and because there won’t be enough doses to reach everyone at first, states are preparing to make tough decisions: Louisiana’s preliminary plan, for example, puts prison guards and food processing workers ahead of teachers and grocery employees. Nevada’s prioritizes education and public transit workers over those in retail and food processing.

Share of workers in essential and frontline jobs, by state

By Matthew Conlen·Note: States may have different definitions of essential workers. | Sources: Labor Market Information Institute, Council for Community and Economic Research, National Bureau of Economic Research, U.S. Bureau of Labor Statistics, Cybersecurity and Infrastructure Security Agency

At this early point, many state plans put at least some people who are older and live independently, or people who have medical conditions, ahead of most essential workers, though that could change after the C.D.C. committee makes a formal recommendation on the next phase.

One occupation whose priority is being hotly debated is teaching. The C.D.C. includes educators as essential workers. But not everyone agrees with that designation.

Marc Lipsitch, an infectious-disease epidemiologist at Harvard’s T.H. Chan School of Public Health, argued that teachers should not be included as essential workers, if a central goal of the committee is to reduce health inequities.

“Teachers have middle-class salaries, are very often white, and they have college degrees,” he said. “Of course they should be treated better, but they are not among the most mistreated of workers.”

Elise Gould, a senior economist at the Economic Policy Institute, disagreed. Teachers not only ensure that children don’t fall further behind in their education, she said, but are also critical to the work force at large.

An empty classroom in Ohio. Public health experts disagree on whether teachers should get a top priority for the vaccine.Credit…Kyle Grillot/Reuters

“When you talk about disproportionate impact and you’re concerned about people getting back into the labor force, many are mothers, and they will have a harder time if their children don’t have a reliable place to go,” she said. “And if you think generally about people who have jobs where they can’t telework, they are disproportionately Black and brown. They’ll have more of a challenge when child care is an issue.”

In September, academic researchers analyzed the Department of Homeland Security’s list of essential workers and found that it broadly mirrored the demographics of the American labor force. The researchers proposed a narrower, more vulnerable category — “frontline workers,” such as food deliverers, cashiers and emergency medical technicians, who must work face to face with others and are thus at greater risk of contracting the virus.

By this definition, said Francine D. Blau, a labor economist at Cornell University and an author of the study, teachers belong in the larger category of essential workers. However, when they work in classrooms rather than remotely, she said, would they fit into the “frontline” group. Individual states categorize teachers differently.

Dr. Blau said that if supplies are short, frontline workers should be emphasized. “These are a subset of essential workers who, given the nature of their jobs, must provide their labor in person. Prioritizing them makes sense given the heightened risk that they face.”

The analysis, a working paper for the National Bureau of Economic Research, is in line with other critics, who say that the list of essential workers is too wide-ranging.

“If groups are too large, then you’re not really focusing on priorities,” said Saad B. Omer, director of the Yale Institute for Global Health, who worked on the vaccination frameworks for the W.H.O. and the National Academies.

The essential workers on the federal list make up nearly 70 percent of the American labor force, the researchers said, compared with 42 percent for the frontline workers. Women made up 39 percent of frontline workers and, in certain occupations, far more. Frontline workers’ education levels are lower, as are their wages — on average, just under $22 an hour. The proportion of Black and Hispanic workers is higher than in the broader category of essential workers.

Death vs. transmission

A nursing home resident in Brooklyn being taken to a hospital last April. The C.D.C. recommends that residents of long-term care facilities, along with health care workers, get the very first vaccines.Credit…Lucas Jackson/Reuters

Some health policy experts said that to prioritize preventing deaths rather than reducing virus transmission was simply a pragmatic choice, because there won’t be enough vaccine initially available to make a meaningful dent in contagion. A more effective use of limited quantities, they say, is to save the lives of the most frail.

Moreover, vaccine trial results so far show only that the shots can protect the individuals who receive them. The trials have not yet demonstrated that a vaccinated person would not infect others. Though scientists believe that is likely to be the case, it has yet to be proved.

Harald Schmidt, an expert in ethics and health policy at the University of Pennsylvania, said that it is reasonable to put essential workers ahead of older adults, given their risks, and that they are disproportionately minorities. “Older populations are whiter, ” Dr. Schmidt said. “Society is structured in a way that enables them to live longer. Instead of giving additional health benefits to those who already had more of them, we can start to level the playing field a bit.”

But to protect older people more at risk, he called on the C.D.C. committee to also integrate the agency’s own “social vulnerability index.”

The index includes 15 measures derived from the census, such as overcrowded housing, lack of vehicle access and poverty, to determine how urgently a community needs health support, with the goal of reducing inequities.

In a new analysis of the states’ preliminary vaccine plans, Dr. Schmidt found that at least 18 states intended to apply the index. Tennessee, for one, has indicated that it will reserve some of its early allotments for disadvantaged communities.

Still, some people believe it is wrong to give racial and socioeconomic equity more weight than who is most likely to die.

“They need to have bombproof, fact-based, public-health-based reasons for why one group goes ahead of another,” said Chuck Ludlam, a former Senate aide and biotech industry lobbyist who protested putting essential workers ahead of older people in comments to the committee. “They have provided no explanation here that will withstand public scrutiny.”

Blurred lines, many unknowns

Employees of the Four Seasons Rehabilitation and Nursing in Westland, Mich., demonstrated for better pay and protections during an outbreak of Covid-19 in October.Credit…Emily Elconin/Reuters

Further complicating matters, the different priority groups discussed by the C.D.C. committee are overlapping — many essential workers have high-risk conditions, and some are older than 65. Some states have suggested that they will prioritize only essential workers who come face to face with the public, while others have not prioritized them at all.

Even some people whose allegiance lies with one group have made the case that others should have an earlier claim on the vaccine. Marc Perrone, president of the United Food and Commercial Workers Union, which represents 1.3 million grocery and food processing workers, said that despite the high rate of infection among his members, he thought that older adults should go first.

“Here’s the thing: Everybody’s got a grandmother or grandfather,” Mr. Perrone said. “And I do believe almost everybody in this country would want to protect them, or their aging parents.”

But Dr. Nirav Shah, Maine’s top public health official, said he respectfully disagreed, repeating the explanation he had given his in-laws — who are older but in good health and able to socially distance.

He said: “I’ve told them: ‘You know what? I’m sorry, but there are others that I need to get this vaccine to first, so that when you guys get vaccinated, the world you come back into is ready to receive you.’”

All these plans are, of course, unfurling with essential information still unknown.Many state officials said that as on-the-ground realities emerge, they fully expect their plans to evolve.

One uncertainty: given the high rates of apprehension swirling around this vaccine, how many people in the early groups will actually line up for it?

“If a high proportion of essential workers decline to get the vaccine, states will have to quickly move onto the next group anyway,” said Dr. Prosser, the University of Michigan health analyst. “Because once the vaccines arrive, they will have to be used in a certain amount of time before they degrade.”

Additional work by Jugal K. Patel.

The Swiss Cheese Model of Pandemic Defense

The Swiss Cheese Model of Pandemic Defense

It’s not edible, but it can save lives. The virologist Ian Mackay explains how.

The multilayered “Swiss cheese” model was devised in the 1990s to improve industrial safety. Ian Mackay, a virologist at the University of Queensland, recently adapted it for the coronavirus pandemic. “It’s important to use more slices to prevent those volatile holes from aligning and letting virus through,” he said.
The multilayered “Swiss cheese” model was devised in the 1990s to improve industrial safety. Ian Mackay, a virologist at the University of Queensland, recently adapted it for the coronavirus pandemic. “It’s important to use more slices to prevent those volatile holes from aligning and letting virus through,” he said.Credit…Ian M. Mackay

By

  • Dec. 5, 2020, 5:00 a.m. ET

Lately, in the ongoing conversation about how to defeat the coronavirus, experts have made reference to the “Swiss cheese model” of pandemic defense.

The metaphor is easy enough to grasp: Multiple layers of protection, imagined as cheese slices, block the spread of the new coronavirus, SARS-CoV-2, the virus that causes Covid-19. No one layer is perfect; each has holes, and when the holes align, the risk of infection increases. But several layers combined — social distancing, plus masks, plus hand-washing, plus testing and tracing, plus ventilation, plus government messaging — significantly reduce the overall risk. Vaccination will add one more protective layer.

“Pretty soon you’ve created an impenetrable barrier, and you really can quench the transmission of the virus,” said Dr. Julie Gerberding, executive vice president and chief patient officer at Merck, who recently referenced the Swiss cheese model when speaking at a virtual gala fund-raiser for MoMath, the National Museum of Mathematics in Manhattan.

“But it requires all of those things, not just one of those things,” she added. “I think that’s what our population is having trouble getting their head around. We want to believe that there is going to come this magic day when suddenly 300 million doses of vaccine will be available and we can go back to work and things will return to normal. That is absolutely not going to happen fast.”

Rather, Dr. Gerberding said in a follow-up email, expect to see “a gradual improvement in protection, first among the highest need groups, and then more gradually among the rest of us.” Until vaccines are widely available and taken, she said, “we will need to continue masks and other common-sense measures to protect ourselves and others.”

In October, Bill Hanage, an epidemiologist at the Harvard T.H. Chan School of Public Health, retweeted an infographic rendering of the Swiss cheese model, noting that it included “things that are personal *and* collective responsibility — note the ‘misinformation mouse’ busy eating new holes for the virus to pass through.”

“One of the first principles of pandemic response is, or ought to be, clear and consistent messaging from trusted sources,” Dr. Hanage said in an email. “Unfortunately the independence of established authorities like the C.D.C. has been called into question, and trust needs to be rebuilt as a matter of urgency.” A catchy infographic is a powerful message, he said, but ultimately requires higher-level support.

The Swiss cheese concept originated with James T. Reason, a cognitive psychologist, now a professor emeritus at the University of Manchester, England, in his 1990 book, “Human Error.” A succession of disasters — including the Challenger shuttle explosion, Bhopal and Chernobyl — motivated the concept, and it became known as the “Swiss cheese model of accidents,” with the holes in the cheese slices representing errors that accumulate and lead to adverse events.

The model has been widely used by safety analysts in various industries, including medicine and aviation, for many years. (Dr. Reason did not devise the “Swiss cheese” label; that is attributed to Rob Lee, an Australian air-safety expert, in the 1990s.) The model became famous, but it was not accepted uncritically; Dr. Reason himself noted that it had limitations and was intended as a generic tool or guide. In 2004, at a workshop addressing an aviation accident two years earlier near Überlingen, Germany, he delivered a talk with the title, “Überlingen: Is Swiss cheese past its sell-by date?”

In 2006, a review of the model, published by the Eurocontrol Experimental Center, recounted that Dr. Reason, while writing the book chapter “Latent errors and system disasters,” in which an early version of the model appears, was guided by two notions: “the biological or medical metaphor of pathogens, and the central role played by defenses, barriers, controls and safeguards (analogous to the body’s autoimmune system).”

The cheese metaphor now pairs fairly well with the coronavirus pandemic. Ian M. Mackay, a virologist at the University of Queensland, in Brisbane, Australia, saw a smaller version on Twitter, but thought that it could do with more slices, more information. He created, with collaborators, the “Swiss Cheese Respiratory Pandemic Defense” and engaged his Twitter community, asking for feedback and putting the visualization through many iterations. “Community engagement is very high!” he said. Now circulating widely, the infographic has been translated into more than two dozen languages.

Dr. Mackay, a creator of the “Swiss Cheese Respiratory Pandemic Defense.”
Dr. Mackay, a creator of the “Swiss Cheese Respiratory Pandemic Defense.”Credit…Faye Sakura for The New York Times

“This multilayered approach to reducing risk is used in many industries, especially those where failure could be catastrophic,” Dr. Mackay said, via email. “Death is catastrophic to families, and for loved ones, so I thought Professor Reason’s approach fit in very well during the circulation of a brand-new, occasionally hidden, sometimes severe and occasionally deadly respiratory virus.”

The following is an edited version of a recent email conversation with Dr. Mackay.

Q. What does the Swiss cheese model show?

A. The real power of this infographic — and James Reason’s approach to account for human fallibility — is that it’s not really about any single layer of protection or the order of them, but about the additive success of using multiple layers, or cheese slices. Each slice has holes or failings, and those holes can change in number and size and location, depending on how we behave in response to each intervention.

Take masks as one example of a layer. Any mask will reduce the risk that you will unknowingly infect those around you, or that you will inhale enough virus to become infected. But it will be less effective at protecting you and others if it doesn’t fit well, if you wear it below your nose, if it’s only a single piece of cloth, if the cloth is a loose weave, if it has an unfiltered valve, if you don’t dispose of it properly, if you don’t wash it, or if you don’t sanitize your hands after you touch it. Each of these are examples of a hole. And that’s in just one layer.

To be as safe as possible, and to keep those around you safe, it’s important to use more slices to prevent those volatile holes from aligning and letting virus through.

Q. What have we learned since March?

A. Distance is the most effective intervention; the virus doesn’t have legs, so if you are physically distant from people, you avoid direct contact and droplets. Then you have to consider inside spaces, which are especially in play during winter or in hotter countries during summer: the bus, the gym, the office, the bar or the restaurant. That’s because we know SARS-CoV-2 can remain infectious in aerosols (small floaty droplets) and we know that aerosol spread explains Covid-19 superspreading events. Try not to be in those spaces with others, but if you have to be, minimize your time there (work from home if you can) and wear a mask. Don’t go grocery shopping as often. Hold off on going out, parties, gatherings. You can do these things later.

We don’t talk about eye coverings much, but we should, because we don’t know enough about the role of eyes in transmission. We do know that eyes are a window to the upper respiratory tract.

Q. Where does the “misinformation mouse” fit in?

A. The misinformation mouse can erode any of those layers. People who are uncertain about an intervention may be swayed by a loud and confident-sounding voice proclaiming that a particular layer is ineffective. Usually, that voice is not an expert on the subject at all. When you look to the experts — usually to your local public health authorities or the World Health Organization — you’ll find reliable information.

An effect doesn’t have to be perfect to reduce your risk and the risk to those around you. We need to remember that we’re all part of a society, and if we each do our part, we can keep each other safer, which pays off for us as well.

Another example: We look both ways for oncoming traffic before crossing a road. This reduces our risk of being hit by a car but doesn’t reduce it to zero. A speeding car could still come out of nowhere. But if we also cross with the lights, and keep looking as we walk, and don’t stare at our phone, we drastically reduce our risk of being hit.

We’re already used to doing that. When we listen to the loud nonexperts who have no experience in protecting our health and safety, we are inviting them to have an impact in our lives. That’s not a risk we should take. We just need to get used to these new risk-reduction steps for today’s new risk — a respiratory virus pandemic, instead of a car.

Q. What is our individual responsibility?

A. We each need to do our part: stay apart from others, wear a mask when we can’t, think about our surroundings, for example. But we can also expect our leadership to be working to create the circumstances for us to be safe — like regulations about the air exchange inside public spaces, creating quarantine and isolation premises, communicating specifically with us (not just at us), limiting border travel, pushing us to keep getting our health checks, and providing mental health or financial support for those who suffer or can’t get paid while in a lockdown.

Q. How can we make the model stick?

A. We each use these approaches in everyday life. But for the pandemic, this all feels new and like a lot of extra work. Because everything is new. In the end, though, we’re just forming new habits. Like navigating our latest phone’s operating system or learning how to play that new console game I got for my birthday. It might take some time to get across it all, but it’s worthwhile. In working together to reduce the risk of infection, we can save lives and improve health.

And as a bonus, the multilayered risk reduction approach can even decrease the number of times we get the flu or a bad chest cold. Also, sometimes slices sit under a mandate — it’s important we also abide by those rules and do what the experts think we should. They’re looking out for our health.

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