Tagged Johnson & Johnson

Covid-19 Vaccine Side Effects: Your Questions Answered

The most common questions about vaccination side effects, answered.

Every day nearly three million people in the United States are getting the Covid-19 vaccine. And every new jab prompts new questions about what to expect after vaccination.

Last week I asked readers to send me their questions about vaccinations. Here are some answers.

Q: I’ve heard the Covid vaccine side effects, especially after the second dose, can be really bad. Should I be worried?

Short-lived side effects like fatigue, headache, muscle aches and fever are more common after the second dose of both the Pfizer-BioNTech and the Moderna vaccines, which each require two shots. (The Johnson & Johnson vaccine requires only a single shot.) Patients who experience unpleasant side effects after the second dose often describe feeling as if they have a bad flu and use phrases like “it flattened me” or “I was useless for two days.” During vaccine studies, patients were advised to schedule a few days off work after the second dose just in case they needed to spend a day or two in bed.

Data collected from v-safe, the app everyone is encouraged to use to track side effects after vaccination, also show an increase in reported side effects after the second dose. For instance, about 29 percent of people reported fatigue after the first Pfizer-BioNTech shot, but that jumped to 50 percent after the second dose. Muscle pain rose from 17 percent after the first shot to 42 percent after the second. While only about 7 percent of people got chills and fever after the first dose, that increased to about 26 percent after the second dose.

The New York Times interviewed several dozen of the newly vaccinated in the days afterward. They recounted a wide spectrum of responses, from no reaction at all to symptoms like uncontrolled shivering and “brain fog.” While these experiences aren’t pleasant, they are a sign that your own immune system is mounting a potent response to the vaccine.

Q: Is it true that women are more likely to get worse side effects from the vaccine than men?

An analysis of safety data from the first 13.7 million Covid-19 vaccine doses given to Americans found that side effects were more common in women. And while severe reactions to the Covid vaccine are rare, nearly all the cases of anaphylaxis, or life-threatening allergic reactions, occurred in women.

The finding that women are more likely to report and experience unpleasant side effects to the Covid vaccine is consistent with other vaccines as well. Women and girls can produce up to twice as many antibodies after receiving flu shots and vaccines for measles, mumps and rubella (M.M.R.) and hepatitis A and B. One study found that over nearly three decades, women accounted for 80 percent of all adult anaphylactic reactions to vaccines.

While it’s true that women may be more likely to report side effects than men, the higher rate of side effects in women also has a biological explanation. Estrogen can stimulate an immune response, whereas testosterone can blunt it. In addition, many immune-related genes are on the X chromosome, of which women have two copies and men have only one. These robust immune responses help to explain why 80 percent of autoimmune diseases afflict women. You can read more about women and vaccine side effects here.

Q: I didn’t have any side effects. Does that mean my immune system didn’t respond and the vaccine isn’t working?

Side effects get all the attention, but if you look at the data from vaccine clinical trials and the real world, you’ll see that many people don’t experience any side effects beyond a sore arm. In the Pfizer vaccine trials, about one out of four patients reported no side effects. In the Moderna trials, 57 percent of patients (64 or younger) reported side effects after the first dose — that jumped to 82 percent after the second dose, which means almost one in five patients reported no reaction after the second shot.

A lack of side effects does not mean the vaccine isn’t working, said Dr. Paul Offit, a professor at the University of Pennsylvania and a member of the Food and Drug Administration’s vaccine advisory panel. Dr. Offit noted that during the vaccine trials, a significant number of people didn’t report side effects, and yet the trials showed that about 95 percent of people were protected. “That proves you don’t have to have side effects in order to be protected,” he said.

Nobody really knows why some people have a lot of side effects and others have none. We do know that younger people mount stronger immune responses to vaccines than older people, whose immune systems get weaker with age. Women typically have stronger immune responses than men. But again, these differences don’t mean that you aren’t protected if you don’t feel much after getting the shot.

Scientists still aren’t sure how effective the vaccines are in people whose immune systems may be weakened from certain medical conditions, such as cancer treatments or H.I.V. infection or because they are taking immune suppressing drugs. But most experts believe the vaccines still offer these patients some protection against Covid-19.

The bottom line is that even though individual immune responses can vary, the data collected so far show that all three vaccines approved in the United States — Pfizer-BioNTech, Moderna and Johnson & Johnson — are effective against severe illness and death from Covid-19.

Q: I took Tylenol before I had my Covid vaccine shots and had very little reaction to the shots. Did I make a big mistake?

You shouldn’t try to stave off discomfort by taking a pain reliever before getting the shot. The concern is that premedicating with a pain reliever like acetaminophen (Tylenol) or ibuprofen (Advil, Motrin), which can prevent side effects like arm soreness as well as fever or headache, might also blunt your body’s immune response.

While it’s possible that taking a pain reliever before your shots might have dampened your body’s immune response, vaccine experts say you shouldn’t worry, and you shouldn’t try to get another shot. Studies of other vaccines suggest that while premedicating can dull the body’s immune response to a vaccine, your immune system can still mount a strong enough defense to fight infection. A review of studies of more than 5,000 children compared antibody levels in children who took pain relievers before and after vaccinations and those who did not. They found that pain relievers did not have a meaningful impact on immune response, and that children in both groups generated adequate levels of antibodies after their shots.

The high efficacy of all the Covid vaccines suggests that even if taking Tylenol before the shot did blunt your body’s immune response, there’s some wiggle room, and you are likely still well protected against Covid-19. “You should feel reassured that you’ll have enough of an immune response that you’ll will be protected, especially for vaccines that are this good,” said Dr. Offit.

Q: What about taking a pain reliever after the shot?

“It’s OK to treat” side effects with a pain reliever, said Dr. Offit, but if you don’t really need one, “don’t take it.”

While most experts agree it’s safe to take a pain reliever to relieve discomfort after you get vaccinated, they advise against taking it after the shot as a preventive or if your symptoms are manageable without it. The concern with taking an unnecessary pain reliever is that it could blunt some of the effects of the vaccine. (In terms of the vaccine, there’s no meaningful difference if you choose acetaminophen or ibuprofen.)

During the Moderna trial, about 26 percent of people took acetaminophen to relieve side effects, and the overall efficacy of the vaccine still was 94 percent.

Q: Are the side effects worse if you’ve already had Covid-19?

Research and anecdotal reports suggest that people with a previously diagnosed Covid-19 infection may have a stronger reaction and more side effects after their first dose of vaccine compared to those who were never infected with the virus. A strong reaction to your first dose of vaccine also might be a sign that you were previously infected, even if you weren’t aware of it.

If you previously tested positive for Covid-19 or had a positive antibody blood test, be prepared for a stronger reaction to your first dose, and consider scheduling a few days off work just in case. Not only will it be more comfortable to stay home and recover in bed, the vaccine side effects can resemble the symptoms Covid-19, and your co-workers won’t want to be near you anyway.

Q: I had Covid-19 already. Does that mean I can just get one dose?

Studies suggest that one dose might be adequate for people who have a previously confirmed case of Covid-19, but so far the medical guidelines haven’t changed. If you’ve received the Pfizer-BioNTech or Moderna vaccines, you should plan to get your second dose even if you’ve had Covid-19. Skipping your second dose could create problems if your employer or an airline ask to see proof of vaccination in the future. If you live in an area where the single-dose Johnson & Johnson vaccine is available, then you can be fully vaccinated after just one dose. You can read more here about the vaccine response in people who’ve had Covid-19.

Q: Will the vaccines work against the new variants that have emerged around the world?

The vaccines appear to be effective against a new variant that originated in Britain and is quickly becoming dominant in the United States. But some variants of the coronavirus, particularly one first identified in South Africa and one in Brazil, appear to be more adept at dodging antibodies in vaccinated people.

While that sounds worrisome, there’s reason to be hopeful. Vaccinated people exposed to a more resistant variant still appear to be protected against serious illness. And scientists have a clear enough understanding of the variants that they already are working on developing booster shots that will target the variants. The variants identified in South Africa and Brazil are not yet widespread in the United States.

People who are vaccinated should still wear masks in public and comply with public health guidelines, but you shouldn’t live in fear of variants, said Dr. Peter J. Hotez, dean of the National School of Tropical Medicine at Baylor College of Medicine in Houston. “If you’re vaccinated, you should feel pretty confident about how protected you are,” said Dr. Hotez. “It’s unlikely you’ll ever go to a hospital or an I.C.U. with Covid-19. In time you’re going to see a recommendation for a booster.”

I hope these answers will reassure you about your own vaccine experience. You can find a more complete list of questions and answers in our special vaccine tool “Answers to All Your Questions About Getting Vaccinated Against Covid-19.”

What to Expect When You Get Your Covid Vaccine

What to Expect When You Get Your Covid Vaccine

Kevin Mohatt for The New York Times

With more Americans becoming eligible for vaccination, many have questions about what the experience is like.

Here, Times science and health reporters answer some frequently asked questions about vaccination →

Mar. 10, 2021
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The Pfizer-BioNTech Vaccine Is Said to Be Powerfully Protective in Adolescents

A clinical trial found no infections among vaccinated children ages 12 to 15, the companies said, and there were no serious side effects. The data have not yet been reviewed by independent experts.

The Pfizer-BioNTech coronavirus vaccine is extremely effective in adolescents 12 to 15 years old, perhaps even more so than in adults, the companies reported on Wednesday. No infections were found among children who received the vaccine in a recent clinical trial, the drug makers said; the children produced strong antibody responses and experienced no serious side effects.

The findings, if they hold up, may speed a return to normalcy for millions of American families. Depending on regulatory approval, vaccinations could begin before the start of the next academic year for middle school and high school students, and for elementary school children not long after.

The companies announced the results in a news release that did not include detailed data from the trial, which has not yet been peer-reviewed nor published in a scientific journal. Still, the news drew praise and excitement from experts.

“Oh my god, I’m so happy to see this — this is amazing,” said Akiko Iwasaki, an immunologist at Yale University. If the vaccines’s performance in adults was A-plus, the results in children were “A-plus-plus.”

The good news arrives even as the country records another rise in infections and health officials renew calls for Americans to heed precautions and get vaccinated. On Monday, Dr. Rochelle Walensky, director of the Centers for Disease Control and Prevention, said that rising cases had left her with sense of “impending doom,” while President Biden called on state and local officials to reinstate mask mandates.

Vaccination efforts are accelerating throughout the nation. As of Tuesday, 29 percent of adults had received at least one dose of a coronavirus vaccine, and 16 percent had been fully inoculated, according to the C.D.C.

But the country cannot hope to reach herd immunity — the point at which immunity becomes so widespread that the coronavirus slows its crawl through the population — without also inoculating the youngest Americans, some experts say. Children under 18 account for about 23 percent of the population in the United States.

“The sooner that we can get vaccines into as many people as possible, regardless of their age, the sooner we will be able to really feel like we’re ending this pandemic for good,” said Angela Rasmussen, a virologist affiliated with Georgetown University in Washington.

Data from Israel suggest that vaccinating adults alone can significantly decrease the number of cases, but “long term, to hit the herd immunity threshold, we will have to vaccinate children,” she said.

The trial included 2,260 adolescents ages 12 to 15. The children received two doses of the vaccine three weeks apart — the same amounts and schedule used for adults — or a placebo of saltwater.

The researchers recorded 18 cases of coronavirus infection in the placebo group, and none among the children who received the vaccine. Still, the low number of infections makes it difficult to be too specific about the vaccine’s efficacy in the population at large, Dr. Rasmussen said.

“But obviously, it looks good for the vaccine if there were zero Covid cases among the vaccinated people,” she added.

The adolescents who got the vaccine produced much higher levels of antibodies on average, compared with participants 16 to 25 years of age in an earlier trial. The children experienced the same minor side effects as older participants, although the companies declined to be more specific.

Dr. Iwasaki said she had expected antibody levels in adolescents to be comparable to those in young adults. “But they’re getting even better levels from the vaccines,” she said. “That’s really incredible.”

She and other experts cautioned that the vaccine might be less effective in children, and adults, against some of the variants that have begun circulating in the United States.

Pfizer and BioNTech have begun a clinical trial of the vaccine in children under 12 and started inoculations of children ages 5 to 11 just last week. Company scientists plan to start testing the vaccine next week in even younger children, ages 2 to 5, followed by trials in children ages 6 months to 2 years.

Results from that three-phase trial are expected in the second half of the year, and the companies hope to make the vaccine available for children under 12 early next year.

“We share the urgency to expand the use of our vaccine to additional populations and are encouraged by the clinical trial data from adolescents between the ages of 12 and 15,” Albert Bourla, Pfizer’s chairman and chief executive officer, said in a statement.

Moderna has also been testing its vaccine in children. Results from a trial in adolescents ages 12 to 17 are expected in the next few weeks and in children 6 months to 12 years old in the second half of this year.

AstraZeneca started testing its vaccine in children 6 months and older last month, and Johnson & Johnson has said it will wait for results from trials in older children before testing its vaccine in children under 12.

Some parents have said they are reluctant to immunize their children because the risk posed by the virus is low. Children make up fewer than 1 percent of deaths from Covid-19, but about 2 percent of children who get the illness require hospital care.

The new results may not sway all of those parents, but they may reassure parents who have been wary of the vaccines, said Jennifer Nuzzo, an epidemiologist at the Johns Hopkins Center for Health Security.

“While I don’t think we have to wait until children are vaccinated to fully reopen schools, being able to vaccinate children may help some families feel safer about returning to school,” she said.

Pfizer and BioNTech plan to request from the Food and Drug Administration an amendment to the emergency use authorization for their vaccine, in hopes of beginning immunizations of older children before the start of the next school year. The companies also are planning to submit their data for peer review and publication in a scientific journal.

They will monitor the participants for two years after the second dose to assess the vaccine’s long-term safety and efficacy. Side effects of vaccines are usually apparent within the first six weeks, said Dr. Kristin Oliver, a pediatrician and vaccine expert at Mount Sinai Hospital in New York. “Still, it’s good to know that safety monitoring is going to continue,” she said.

The C.D.C. recommends that people avoid getting other vaccines for two weeks before and after receiving the two doses of the coronavirus vaccine.

But children receive more vaccines in the few weeks before the school year than at any other time, Dr. Oliver noted, so pediatricians and parents should aim to get those other immunizations done earlier than usual.

The coronavirus vaccines should ideally be given by pediatricians who have deep experience in immunizing children, Dr. Oliver added. “Now is the time to start planning how that rollout is going to take place in this age group,” she said.

Pfizer Begins Testing Its Vaccine in Young Children

Other drug makers have begun similar trials of their Covid-19 vaccines. If they work in children younger than 12 as expected, it will be easier for the U.S. to reach herd immunity.

Pfizer has begun testing its Covid-19 vaccine in children under 12, a significant step in turning back the pandemic. The trial’s first participants, a pair of 9-year-old twin girls, were immunized at Duke University in North Carolina on Wednesday.

Results from the trial are expected in the second half of the year, and the company hopes to vaccinate younger children early next year, said Sharon Castillo, a spokeswoman for the pharmaceutical company.

Moderna also is beginning a trial of its vaccine in children six months to 12 years of age. Both companies have been testing their vaccines in children 12 and older, and expect those results in the next few weeks.

AstraZeneca last month began testing its vaccine in children six months and older, and Johnson & Johnson has said it plans to extend trials of its vaccine to young children after assessing its performance in older children.

Immunizing children will help schools to reopen as well as help to end the pandemic, said Dr. Emily Erbelding, an infectious diseases physician at the National Institutes of Health who oversees testing of Covid-19 vaccines in special populations.

An estimated 80 percent of the population may need to be vaccinated for the United States to reach herd immunity, the threshold at which the coronavirus runs out of people to infect. Some adults may refuse to be vaccinated, and others may not produce a robust immune response.

Children under 18 account for about 23 percent of the population in the United States, so even if a vast majority of adults opt for vaccines, “herd immunity might be hard to achieve without children being vaccinated,” Dr. Erbelding said.

Pfizer had initially said it would wait for data from older children before starting trials of its vaccine in children under 12. But “we were encouraged by the data from the 12 to 15 group,” said Ms. Castillo, who did not elaborate on the results so far.

Scientists will test three doses of the Pfizer vaccine — 10, 20 and 30 micrograms — in 144 children. Each dose will be assessed first in children 5 through 11 years of age, then in children ages 2 through 4 years, and finally in the youngest group, six months to 2 years.

After determining the most effective dose, the company will test the vaccine in 4,500 children. About two-thirds of the participants will be randomly selected to receive two doses 21 days apart; the remaining will get two placebo shots of saline. The researchers will assess the children’s immune response in blood drawn seven days after the second dose.

“It sounds like a good plan, and it’s exciting that another Covid-19 vaccine is moving forward with trials in children,” said Dr. Kristin Oliver, a pediatrician and vaccine expert at Mount Sinai Hospital in New York.

Dr. Oliver said about half of the parents she sees in practice are eagerly waiting for vaccines, and even to volunteer their children for clinical trials, while the rest are skeptical because comparatively few children become seriously ill from coronavirus infection.

Both groups of parents will benefit from knowing exactly how safe and effective the vaccines are in children, she said.

Children represent 13 percent of all reported cases in the United States. More than 3.3 million children have tested positive for the virus, at least 13,000 have been hospitalized and at least 260 have died, noted Dr. Yvonne Maldonado, who represents the American Academy of Pediatrics on the federal Advisory Committee on Immunization Practices.

The figures do not fully capture the damage to children’s health. “We don’t know what the long-term effects of Covid infection are going to be,” Dr. Maldonado said.

Other vaccines have helped to control many horrific childhood diseases that can cause long-term complications, she added: “For some of us who’ve seen that, we don’t want to go back to those days.”

Children often react more strongly to vaccines than adults do, and infants and toddlers in particular can experience high fevers. Any side effects are likely to appear soon after the shot, within the first week and certainly within the first few weeks, experts have said.

Some vaccines are tested only in animals before being assessed in children, and have to be monitored carefully for side effects.

“But this is a little different, because we’ve already had experience with tens of millions of people with these vaccines,” Dr. Maldonado said. “So there’s a higher degree of confidence now in giving this vaccine to kids.”

Some experts suggested that the Food and Drug Administration may require up to six months of safety data from studies of children before authorizing the Covid-19 vaccines. But a spokeswoman said the agency did not expect six months of safety data to support the vaccines’ authorization.

The Pfizer-BioNTech vaccine is authorized for children 16 through 18 years old, and the authorization for that age group was based on just two months of safety data, she said.

Parents will want to know how the companies and the F.D.A. plan to monitor and disclose side effects from the vaccines, and how long they will continue to follow trial participants after the vaccines’ authorization, Dr. Oliver said.

“I think everyone has learned throughout this,” she said. “The more transparent you can be, the better.”

Plan to Ditch the Mask After Vaccination? Not So Fast.

Plan to Ditch the Mask After Vaccination? Not So Fast.

It’s not clear how easily vaccinated people may spread the virus, but the answer to that question is coming soon. Until then, scientists urge caution.

A health care worker prepared a dose of the Pfizer-BioNTech vaccine at a vaccination site in San Francisco on Monday.
A health care worker prepared a dose of the Pfizer-BioNTech vaccine at a vaccination site in San Francisco on Monday.Credit…Mike Kai Chen for The New York Times
Apoorva Mandavilli

  • March 3, 2021, 3:23 p.m. ET

With 50 million Americans immunized against the coronavirus, and millions more joining the ranks every day, the urgent question on many minds is: When can I throw away my mask?

It’s a deeper question than it seems — about a return to normalcy, about how soon vaccinated Americans can hug loved ones, get together with friends, and go to concerts, shopping malls and restaurants without feeling threatened by the coronavirus.

Certainly many state officials are ready. On Tuesday, Texas lifted its mask mandate, along with all restrictions on businesses, and Mississippi quickly followed suit. Governors in both states cited declining infection rates and rising numbers of citizens getting vaccinated.

But the pandemic is not yet over, and scientists are counseling patience.

It seems clear that small groups of vaccinated people can get together without much worry about infecting one another. The Centers for Disease Control and Prevention is expected shortly to issue new guidelines that will touch on small gatherings of vaccinated Americans.

But when vaccinated people can ditch the masks in public spaces will depend on how quickly the rates of disease drop and what percentage of people remain unvaccinated in the surrounding community.

Why? Scientists do not know whether vaccinated people spread the virus to those who are unvaccinated. While all of the Covid-19 vaccines are spectacularly good at shielding people from severe illness and death, the research is unclear on exactly how well they stop the virus from taking root in an immunized person’s nose and then spreading to others.

It’s not uncommon for a vaccine to forestall severe disease but not infection. Inoculations against the flu, rotavirus, polio and pertussis are all imperfect in this way.

The coronavirus vaccines “are under a lot more scrutiny than any of the previous vaccines ever have been,” said Neeltje van Doremalen, an expert in preclinical vaccine development at the National Institutes of Health’s Rocky Mountain Laboratories in Montana.

And now coronavirus variants that dodge the immune system are changing the calculus. Some vaccines are less effective at preventing infections with certain variants, and in theory could allow more virus to spread.

The research available so far on how well the vaccines prevent transmission is preliminary but promising. “We feel confident that there’s a reduction,” said Natalie Dean, a biostatistician at the University of Florida. “We don’t know the exact magnitude, but it’s not 100 percent.”

Still, even an 80 percent drop in transmissibility might be enough for immunized people to toss their masks, experts said — especially once a majority of the population is inoculated, and as rates of cases, hospitalizations and deaths plummet.

A line to register for a vaccination appointment in San Francisco. Experts say that people who have been inoculated should continue to wear masks to protect others.
A line to register for a vaccination appointment in San Francisco. Experts say that people who have been inoculated should continue to wear masks to protect others.Credit…Mike Kai Chen for The New York Times

But most Americans are still unvaccinated, and more than 1,500 people are dying every day. So given the uncertainty around transmission, even people who are immunized must continue to protect others by wearing masks, experts said.

“They should wear masks until we actually prove that vaccines prevent transmission,” said Dr. Anthony S. Fauci, director of the National Institute for Allergy and Infectious Diseases.

That proof is not yet in hand because the clinical trials for vaccines were designed to test whether the vaccines prevent serious illness and death, which usually reflects the virus’s impact on the lungs. Transmission, on the other hand, is driven by its growth in the nose and throat.

Primed by the vaccine, the body’s immune fighters should curb the virus soon after infection, shortening the infection period and curtailing the amounts in the nose and throat. That ought to significantly reduce the chances that a vaccinated person might infect others.

Animal studies support the theory. In one study, when monkeys were immunized and then exposed to the virus, seven of eight animals had no detectable virus in their noses or lung fluid, noted Juliet Morrison, a virologist at the University of California, Riverside.

Similarly, data from a few dozen participants in the Moderna trial who were tested when they got their second doses suggested that the first dose had decreased cases of infection by about two-thirds.

Another small batch of data emerged recently from the Johnson & Johnson trial. Researchers looked for signs of infection in 3,000 participants up to 71 days after getting the single-dose vaccine. Risk of infection in that study seemed to fall by about 74 percent.

“I think that’s very powerful,” said Dan Barouch, a virologist at Beth Israel Medical Center in Boston, who led one of the trial sites. “Those number estimates could change with more data, but the effect seems quite strong.”

More data is expected in the coming months from both Pfizer-BioNTech and Moderna.

But clinical trials may overestimate the power of a vaccine, because the type of people who choose to participate already tend to be careful and are counseled on precautions during the trial.

Some researchers instead are tracking infections among immunized people in real-world settings. For example, a study in Scotland conducted tests every two weeks, regardless of symptoms, on health care workers who had received the Pfizer-BioNTech vaccine. Investigators found that the vaccine’s effectiveness in preventing infection was 70 percent after one dose, and 85 percent after the second.

Researchers in Israel assessed infections in almost 600,000 immunized people and tried to trace their household contacts. The scientists found a 46 percent drop in infections after the first dose and a 92 percent drop after the second. (The study may have missed infections in people without symptoms.)

But to get a true assessment of transmission, researchers really need to know which immunized people become infected, and then trace the spread of the virus among their contacts with genetic analysis.

“That’s the ideal way to actually do this,” said Dr. Larry Corey, an expert in vaccine development at The Fred Hutchinson Cancer Research Center in Seattle. He is hoping to conduct such a study in college-age students.

Preparing swab samples at a testing site in San Francisco on Tuesday.Credit…Mike Kai Chen for The New York Times

But what precautions should immunized people take until the results from such studies become available? At the moment, many experts believe that what’s permissible will depend to a large extent on the number of cases in the surrounding community.

The higher the number of cases, the greater the likelihood of transmission — and the more effective vaccines must be in order to stop the spread.

“If the case numbers are zero, it doesn’t matter whether it’s 70 percent or 100 percent,” said Zoe McLaren, a health policy expert at the University of Maryland, referring to vaccine effectiveness.

Mask-wearing policies also will depend on how many unvaccinated people remain in the population. Americans may need to remain cautious as long as vaccination rates are low. But people will be able to relax a bit as those rates rise, and begin to return to normalcy once the virus runs out of others to infect.

“A lot of people have in mind that masks are the first thing that you let up on,” Dr. MacLaren said. In fact, she said, masks provide more freedom by allowing people to go to concerts, travel on buses or airplanes, or go shopping even with unvaccinated people around.

Ultimately, masks are a form of civic responsibility, said Sabra Klein, an immunologist at the Johns Hopkins Bloomberg School of Public Health.

“Are you wearing a mask to protect yourself from severe Covid, or are you wearing a mask for public health?” Dr. Klein said. “It’s right to do your part in the community beyond yourself.”

Covid Vaccines: Johnson & Johnson's shot authorized by F.D.A.

F.D.A. Clears Johnson & Johnson’s Shot, the Third Vaccine for U.S.

The authorization of a third Covid-19 vaccine will bring millions more doses within days. But health officials worry that some people will see the vaccine as the inferior choice.

The company plans to ship around 20 million doses by the end of March.
The company plans to ship around 20 million doses by the end of March.Credit…Mark Ralston/Agence France-Presse — Getty Images
  • Feb. 27, 2021, 6:12 p.m. ET

WASHINGTON — The Food and Drug Administration on Saturday authorized Johnson & Johnson’s single-shot Covid-19 vaccine for emergency use, beginning the rollout of millions of doses of a third effective vaccine that could reach Americans by early next week.

The announcement arrived at a critical moment, as the steep decline in coronavirus cases seems to have plateaued and millions of Americans are on waiting lists for shots.

Johnson & Johnson has pledged to provide the United States with 100 million doses by the end of June. When combined with the 600 million doses from the two-shot vaccines made by Pfizer-BioNTech and Moderna slated to arrive by the end of July, there will be more than enough shots to cover any American adult who wants one.

But federal and state health officials are concerned that even with strong data to support it, some people may perceive Johnson & Johnson’s shot as an inferior option.

The new vaccine’s 72 percent efficacy rate in the U.S. clinical trial site — a number scientists have celebrated — falls short of the roughly 95 percent rate found in studies testing the Moderna and Pfizer-BioNTech vaccines. Across all trial sites, the Johnson & Johnson vaccine also showed 85 percent efficacy against severe forms of Covid-19 and 100 percent efficacy against hospitalization and death.

“Don’t get caught up, necessarily, on the number game, because it’s a really good vaccine, and what we need is as many good vaccines as possible,” Dr. Anthony S. Fauci, the government’s top infectious disease expert, said in an interview on Saturday. “Rather than parsing the difference between 94 and 72, accept the fact that now you have three highly effective vaccines. Period.”

If Johnson & Johnson’s vaccine would have been the first to be authorized in the United States instead of the third, “everybody would be doing handstands and back flips and high-fives,” said Dr. James T. McDeavitt, dean of clinical affairs at the Baylor College of Medicine.

On Sunday a committee of vaccine experts who advise the Centers for Disease Control and Prevention will meet to discuss whether certain population groups should be prioritized for the vaccine, guidance that state health officials have been eagerly awaiting in anticipation of the F.D.A.’s authorization.

One administration official familiar with the distribution of the vaccine said that shipments would begin on Monday and deliveries could arrive as soon as Tuesday.

Johnson & Johnson has said it will ship nearly four million doses as soon as the F.D.A. authorizes distribution and another 16 million or so doses by the end of March. That is far fewer than the 37 million doses called for in its $1 billion federal contract, but the contract says that deliveries that are 30 days late will still be considered timely.

The federal government is paying the firm $10 a dose for a total of 100 million doses to be ready by the end of June, substantially less per dose than it agreed to pay Moderna and Pfizer, which developed its vaccine with a German partner, BioNTech.

Johnson & Johnson’s one-dose vaccine will allow states to rapidly increase the number of people who have been fully inoculated. Unlike the other two vaccines, it can be stored at standard refrigeration temperatures for at least three months.

Dr. Danny Avula, Virginia’s vaccine coordinator, is excited by the arrival of the newest vaccine.
Dr. Danny Avula, Virginia’s vaccine coordinator, is excited by the arrival of the newest vaccine.Credit…Carlos Bernate for The New York Times

Dr. Danny Avula, the vaccine coordinator for Virginia, said the Johnson & Johnson shipments would boost the state’s allotment of vaccine next week by nearly one-fifth.

“I’m super-pumped about this,” he said. “A hundred percent efficacy against deaths and hospitalizations? That’s all I need to hear.”

He said the state was planning mass vaccination events specifically for the Johnson & Johnson vaccine, partly to quell any suspicion that it is a lesser product targeted to specific groups.

“It will be super clear that this is Johnson & Johnson, here’s what you need to know about it. If you want to do this, you’re coming in with eyes wide open,” he said. “If not, you will keep your place on the list.”

Michele Roberts, the assistant secretary of Washington State’s health department, said that it would be difficult to explain the technical aspects of how Johnson & Johnson’s vaccine trials differed from those of other drug makers. Because the studies were conducted at different times and with different protocols, precise comparisons can be problematic. All three trials showed the vaccines provided strong protection against Covid-19, especially for severe disease.

Understanding the subtle contrasts requires a lot of “scientific literacy,” she said. “There are so many different factors at play. But those aren’t, you know, quick public messages.”

Even some clinicians misinterpret the differences among the Covid-19 vaccines, health officials said. “They assume it’s apples to apples but it’s apples to oranges, or worse, apples to tires,” said Dr. Nirav Shah, the director of the Maine Center for Disease Control and Prevention.

Last week, Dr. Shah said, the leader of one group of specialty health clinics in his state initially turned down his offer to ship doses of the Johnson & Johnson vaccine, saying his health practitioners were concerned it was less efficacious than the other two.

He said he told him: “Stop right there. We need to have a Zoom conversation right now with your entire medical staff.” Instead, he carefully explained Johnson & Johnson’s results to the provider, who then spoke with his staff. Twenty minutes later, the provider sent him a message saying: “We’re on board. Send us the J & J.”

Some state officials have been frustrated by what they view as a lack of a coordinated plan from the Biden administration on how to deploy the new vaccine. Governors have asked the White House for guidance, but administration officials have so far left it up to the states to decide.

Even though Johnson & Johnson received ample federal support and agreed to manufacture at risk, federal officials familiar with its operation said the company took an overly conservative approach to production, emphasizing scaling up on the back end of its contract.

As a result, Johnson & Johnson is expected deliver the bulk of its 100 million doses in the late spring or early summer. The country will still need them: By the end of May, Pfizer and Moderna have promised to ship enough doses to vaccinate 200 million Americans, leaving roughly 60 million eligible adults still uncovered. But with the spread of more contagious variants of the virus, health officials are anxious to vaccinate as many Americans as fast as possible.

Johnson & Johnson produced its first batch of roughly four million doses at its Dutch plant, federal officials said. The company’s new plant in Baltimore is expected to supply the bulk of its doses for the United States.

Americans are becoming more open to getting Covid-19 vaccines, according to the latest survey from the Kaiser Family Foundation, which has been monitoring attitudes since December. Fifty-five percent of adults now say they have either received one dose or will get it as soon as they can, up from 34 percent in December.

A drive-through Covid-19 vaccination site at Dodger Stadium.Credit…Philip Cheung for The New York Times

But Rupali Limaye, who studies vaccine hesitancy at Johns Hopkins University, said she worried about whether health officials and community leaders would sufficiently emphasize the strengths of the Johnson & Johnson vaccine, including how well it prevents the onset of severe Covid-19, hospitalization and death.

“People will want to know: Why is this one so much less and what does it mean for us?” she said. “I’m worried it’s going to cause more questions than confidence.”

Absent more direction from the federal government, state health officials are consulting with each other about where to direct the new source of supply.

Dr. Marcus Plescia, the chief medical officer for the Association of State and Territorial Health Officials, which represents state health agencies, predicted that “many states are going to be a little bit cautious” about where they initially ship the vaccine.

“You don’t want to say, ‘OK, we’re going to use this vaccine for our rural populations because it’s easier to ship.’” That may trigger a backlash from people who wrongly suspect that for some reason or another, they are being offered a second-rate vaccine, he said.

Dr. Shah of Maine said the new vaccine was particularly well-suited for drive-through vaccination sites, partly because it appeared less likely to trigger the kinds of side effects that require monitoring. Health officials in other states said it might also make sense to direct doses toward transient population groups who might be less likely to show up for second shots. Colleges might be particularly interested.

Dr. Jennifer Dillaha, the state epidemiologist in Arkansas’s health department, said the vaccine’s easier storage conditions could also increase the number of vaccinations in other nonmedical settings, like senior centers or sites in underserved communities that lack pharmacies or health care providers.

In order to limit possible confusion, some state health officials said that they initially plan to direct the new vaccine to new sites, not ones that are already administering the other vaccines.

Dr. Shah said that some pharmacists in Maine would rather handle one type of Covid-19 vaccine at a time. Although that may change, Dr. Shah said, “Every day matters. Anything that is introduced into the workflow that slows down the pace of vaccination hurts us.”

Carl Zimmer contributed reporting.

F.D.A. Expert Panel Endorses Johnson & Johnson’s Vaccine

F.D.A. Expert Panel Endorses Johnson & Johnson’s Vaccine

With this last hurdle cleared, formal authorization of the one-dose vaccine is expected on Saturday and distribution within days.

Vaccinations at the Steve Biko Academic Hospital in Pretoria, South Africa, earlier this week. The shot showed 82 percent against severe Covid in South Africa and 86 percent efficacy in the U.S.
Vaccinations at the Steve Biko Academic Hospital in Pretoria, South Africa, earlier this week. The shot showed 82 percent against severe Covid in South Africa and 86 percent efficacy in the U.S.Credit…Phill Magakoe/Agence France-Presse — Getty Images
  • Feb. 26, 2021, 6:25 p.m. ET

Johnson & Johnson’s Covid-19 vaccine was endorsed on Friday by a panel of experts advising the Food and Drug Administration, clearing the last hurdle before a formal authorization expected on Saturday, according to two people familiar with the agency’s plans. The nation’s first shipments will go out in the days after that.

It will be the third shot made available to the United States in the year since the first surge of coronavirus cases began washing over the country, and it will be the first vaccine to require just one dose instead of two.

Johnson & Johnson’s formulation worked well in clinical trials, particularly against severe disease and hospitalizations, even though it did not match the sky-high efficacy rates of the first two vaccines made by Pfizer-BioNTech and Moderna.

The panel, made up of independent infectious disease experts, statisticians and epidemiologists, voted unanimously in favor of authorizing the vaccine.

“We’re dealing with a pandemic right now,” said Dr. Jay Portnoy, an allergist at Children’s Mercy Hospital in Kansas City, M.O. and a member of the board. “It’s great that we have this vaccine.”

During Johnson & Johnson’s presentation to the panel, Dr. Gregory Poland, a virologist at the Mayo Clinic and a paid external consultant for the company, noted the vaccine’s efficacy, ease of use and low rate of side effects. It “nearly checks all the boxes,” he said. “To me, it is clear that the known benefits vastly outweigh the known risks.”

The vaccine had an overall efficacy rate of 72 percent in the United States and 64 percent in South Africa, where a concerning variant emerged in the fall. The shot showed 86 percent efficacy against severe forms of Covid-19 in the United States, and 82 percent against severe disease in South Africa.

Those are strong numbers, but lower than the roughly 95 percent efficacy rates of Pfizer-BioNTech and Moderna’s vaccines against mild, moderate and severe cases of Covid.

Johnson & Johnson’s vaccine is a single dose and uses a different kind of technology than the authorized vaccines. And the scale and size of the Johnson & Johnson trial was vast, spanning eight countries, three continents and nearly 45,000 participants.

Johnson & Johnson’s vaccine will be the third shot made available to the U.S. since the pandemic began, and it will be the first vaccine to require just one dose instead of two.
Johnson & Johnson’s vaccine will be the third shot made available to the U.S. since the pandemic began, and it will be the first vaccine to require just one dose instead of two.Credit…Phill Magakoe/Agence France-Presse — Getty Images

Although the vaccine works with one shot, studies are underway to determine if a second dose would increase its protective effects.

Dr. Paul Offit, a pediatrician at the Children’s Hospital of Philadelphia and one of the panelists, pointed out on Friday that in early clinical trials that took place over the summer, Johnson & Johnson found that a second dose led to levels of coronavirus antibodies that were almost three times higher than those produced by one dose alone.

The results of Johnson & Johnson’s two-dose, late-stage clinical trial are not expected until July at the earliest. If those results turn out to be better than a single dose, Dr. Offit asked, “Does this then become a two-dose vaccine?”

Dr. Johan Van Hoof, the global head of vaccine research and development at Janssen Pharmaceuticals, the drug development arm of Johnson & Johnson, said that the company decided to pursue the one-shot strategy after its studies on monkeys last spring showed that a single dose was enough to provide strong protection against the disease.

“It’s clear that in a situation of an outbreak, in a raging epidemic, the big challenge is to get the epidemic under control,” he said. “The regimen is extremely well positioned to be used in outbreak situations.”

But Dr. Van Hoof also noted that it will be important to track volunteers who received a single dose to see if their immunity changes in the months to come. It might be necessary to deliver a booster shot for long-term protection. “The big question mark still is, how long does protection last?” he said.

After the vote, the F.D.A. told Johnson & Johnson that it “will rapidly work toward finalization and issuance of an emergency use authorization,” according to a statement. The F.D.A. also said that it had notified other government agencies “so they can execute their plans for timely vaccine distribution.”

Sharon LaFraniere contributed reporting.

Johnson & Johnson’s Vaccine Works Well and May Curb Virus Spread

Johnson & Johnson’s Vaccine Works Well and May Curb Virus Spread

F.D.A. studies show the shot strongly protects against severe illness and may reduce spread of the virus. But the drugmaker has fallen short of initial production goals.

Jacqui Dallimore, a research nurse, delivering a shot to a volunteer in the Johnson & Johnson vaccine trial at the Desmond Tutu H.I.V. Foundation Youth Center in Masiphumelele, South Africa, in December.
Jacqui Dallimore, a research nurse, delivering a shot to a volunteer in the Johnson & Johnson vaccine trial at the Desmond Tutu H.I.V. Foundation Youth Center in Masiphumelele, South Africa, in December.Credit…Joao Silva/The New York Times
  • Feb. 24, 2021, 5:36 p.m. ET

The coronavirus vaccine made by Johnson & Johnson provides strong protection against severe disease and death from Covid-19, and may reduce the spread of the virus by vaccinated people, according to new analyses posted online by the company and the Food and Drug Administration on Wednesday.

The reports provided an in-depth confirmation of the initial results announced by Johnson & Johnson late last month, indicating that the United States is likely to soon have access to a third coronavirus vaccine developed in under a year. The F.D.A. could authorize the vaccine as early as Saturday, depending on a vote by its vaccine advisory panel on Friday, and distribution could begin within days.

If cleared, the vaccine would reach a number of firsts for the U.S. pandemic. Unlike the authorized vaccines made by Pfizer-BioNTech and Moderna, which require two doses, Johnson & Johnson’s is just a single shot, allowing the number of fully vaccinated Americans to rapidly increase once it is deployed. More than 44 million Americans have received at least one dose of the Moderna and Pfizer vaccines, but only around 20 million have received a second dose.

Those earlier vaccines use a new technology called mRNA that needs freezers for long-term storage. Johnson & Johnson’s vaccine, which uses sturdier viruses to deliver genes into cells, can keep for three months at normal refrigeration temperatures, making it easier to distribute and easier for pharmacies and clinics to stock. The White House on Wednesday said around two million doses would be ready to allocate to states next week, with up to another two million for pharmacies and community health centers.

The documents published by the F.D.A. on Wednesday showed that the new vaccine had an overall efficacy rate of 72 percent in the United States and 64 percent in South Africa, where a concerning variant emerged in the fall that is now driving most cases. The efficacy in South Africa was seven percentage points higher than earlier data released by the company showed.

The vaccine also showed 86 percent efficacy against severe forms of Covid-19 in the United States, and 82 percent against severe disease in South Africa. That means that a vaccinated person has a far lower risk of being hospitalized or dying from Covid-19. None of the nearly 22,000 vaccinated people in the trial died of Covid-19.

“The vaccine has definitely met the bar of what’s worthy of rolling out and using. It’s performing well,” said Natalie Dean, a biostatistician at the University of Florida. Another authorized vaccine, and especially one that only requires one dose, could block the spread of the virus more effectively and drive down cases faster. “Having more products available is a huge advantage,” Dr. Dean said.

State health departments around the nation have been eager to take advantage of it. In North Dakota, which has one of the nation’s highest rates of vaccination, members of the state’s vaccine ethics committee met this week to discuss the allocation and distribution of the vaccine, anticipating the F.D.A.’s analysis, said Kylie Hall, a vaccine adviser for the state’s health department. The new data may help guide the state’s decisions on which people to prioritize for the small number of doses that may arrive next week, she said.

“It prevents severe disease and death from Covid,” she said. “That’s the best news we could have.”

But access to the new vaccine could be severely limited at first. Dr. Richard Nettles, the vice president of U.S. medical affairs at Janssen Pharmaceuticals, the drug development arm of Johnson & Johnson, told lawmakers on Tuesday that nearly four million doses would be ready for shipment if the F.D.A. authorizes the vaccine. That is far below the 12 million it had originally pledged to give the federal government by the end of February.

He said that a total of 20 million doses would be ready by the end of March, 17 million fewer doses than the firm’s federal contract envisioned. But he insisted that Johnson & Johnson would fulfill its promise of 100 million doses by the end of June.

Asked about the shortfall on Wednesday, Jeffrey D. Zients, the White House coordinator of the pandemic response, said that the Biden administration discovered when it took office five weeks ago that Johnson & Johnson was behind on manufacturing and needed federal help in obtaining equipment and raw materials.

“It was disappointing when we arrived,” he said, but “I think the progress is real.” He added: “Obviously the prospect of a potential third approved vaccine is very encouraging,” because lack of supply remains the biggest obstacle to the nation’s vaccination effort.

A lab technician worked on blood samples taken from participants in the Johnson & Johnson Covid-19 vaccine trial at a lab in Groblersdal, South Africa, earlier this month.
A lab technician worked on blood samples taken from participants in the Johnson & Johnson Covid-19 vaccine trial at a lab in Groblersdal, South Africa, earlier this month.Credit…Jerome Delay/Associated Press

Johnson & Johnson’s vaccine has a lower efficacy rate than the vaccines from Moderna and Pfizer-BioNTech, which are both around 95 percent.

But in South Africa, the Johnson & Johnson vaccine is so far the clear winner. Novavax’s shot had an efficacy of 49 percent in South Africa. And a small trial in South Africa of the AstraZeneca-Oxford vaccine found that it did not offer much protection at all. The negative results led the South African government to abandon its plan of giving a million doses of AstraZeneca vaccines to health care workers. Last week, the government started giving Johnson & Johnson’s vaccines instead, and has so far administered more than 32,000.

The newly released documents, which include the F.D.A.’s first technical analysis of the company’s 45,000-person clinical trial, presented evidence that the vaccine was safe, with noticeably milder side effects than the Pfizer and Moderna vaccines and without any reports of severe allergic reactions like anaphylaxis.

The vaccine’s protection was consistent across Black, Hispanic and white volunteers, and also across different ages. The trial estimated a lower efficacy, of 42.3 percent, for people over 60 who had risk factors like heart disease or diabetes, a figure that came with a large amount of statistical uncertainty, the F.D.A. noted.

Dr. James Burke, an expert on trial design at the University of Michigan School of Medicine, cautioned that the results found in small subgroups can turn out to be the result of chance. “We’re wrong more than we’re right,” he said. “So we should always tread very cautiously.”

He noted that the trial only recorded 41 cases of Covid-19 in 6,667 people over 60 with comorbidities. “Common sense makes it pretty clear that we can’t make very robust estimates with such a small number of outcomes,” Dr. Burke said.

Preliminary data suggests that the vaccine’s protective effects grow in the weeks after vaccination. After 42 days, for example, only one vaccinated person got Covid-19, whereas 13 people in the placebo group did, which translates to a 92.4 percent efficacy rate. It’s not clear how long the vaccine’s protection will last before it wanes, an uncertainty that hovers over all the coronavirus vaccines, since they have only gone into testing in recent months.

Although several vaccines can protect people from getting sick with Covid-19, it is unclear whether the shots can also prevent people from getting infected and passing the virus to others, leading to a debate about how quickly society can return to normal after inoculations begin.

Moderna’s trial found some hints that vaccinated people were less likely to develop an infection without symptoms. And AstraZeneca found that its vaccine reduced asymptomatic infections by about half.

Johnson & Johnson looked for asymptomatic infections by checking for coronavirus antibodies 71 days after volunteers got a vaccine or a placebo. The new analyses estimate that the vaccine has an efficacy rate of 74 percent against asymptomatic infections. But that calculation was based on a relatively small number of volunteers, and the F.D.A. noted that “There is uncertainty about the interpretation of these data and definitive conclusions cannot be drawn at this time.”

Still, Dr. Dean said the results, while preliminary, were encouraging, especially when combined with other studies suggesting that vaccinated people who did get infected have a lower viral load, potentially making them less infectious.

“I think there’s a lot of good reasons to be optimistic,” she said.

Covid Vaccines for Kids Are Coming, but Not for Many Months

Covid Vaccines for Kids Are Coming, but Not for Many Months

Pfizer and Moderna are testing their vaccines on children 12 and older and hope to have results by the summer.

A 15-year-old participating in Moderna’s teen Covid vaccine trial received a shot in Houston this month.
A 15-year-old participating in Moderna’s teen Covid vaccine trial received a shot in Houston this month.Credit…Brandon Thibodeaux for The New York Times
Apoorva Mandavilli

  • Feb. 12, 2021, 5:00 a.m. ET

As adults at high risk for Covid-19 line up to be immunized against the coronavirus, many parents want to know: When will my child get a vaccine?

The short answer: Not before late summer.

Pfizer and Moderna have enrolled children 12 and older in clinical trials of their vaccines and hope to have results by the summer. Depending on how the vaccines perform in that age group, the companies may then test them in younger children. The Food and Drug Administration usually takes a few weeks to review data from a clinical trial and authorize a vaccine.

Three other companies — Johnson & Johnson, Novavax and AstraZeneca — also plan to test their vaccines in children, but are further behind.

When researchers test drugs or vaccines in adults first, they typically then move down the age brackets, watching for any changes in the effective dose and for unexpected side effects.

“It would be pretty unusual to start going down into children at an early stage,” said Dr. Emily Erbelding, an infectious diseases physician at the National Institutes of Health who oversees testing of Covid-19 vaccines in special populations.

Some vaccines — those that protect against pneumococcal or meningococcal bacteria or rotavirus, for example — were tested in children first because they prevent pediatric diseases. But it made sense for coronavirus vaccines to be first tested in and authorized for adults because the risk of severe illness and death from Covid-19 increases sharply with age, said Paul Offit, a professor at the University of Pennsylvania and a member of the F.D.A.’s vaccine advisory panel.

“We’re trying to save lives, keep people out of the I.C.U., keep them from dying,” Dr. Offit said. That means prioritizing vaccines for the oldest people and for those with underlying conditions.

People younger than 21 account for about one-quarter of the population in the United States, but they make up less than 1 percent of deaths from Covid-19. Still, about 2 percent of children who get Covid-19 require hospital care, and at least 227 children in the United States have died of the disease.

“It is a significant disease in children, just not necessarily when you compare it to adults,” said Dr. Kristin Oliver, a pediatrician and vaccine expert at Mount Sinai Hospital in New York.

Children will also need to be vaccinated in order for the United States to approach herd immunity — that long-promised goal at which the pandemic slows to a halt because the virus runs out of people to infect.

Scientists have estimated that 70 to 90 percent of the population might need to be immunized against the coronavirus to reach herd immunity, especially with more contagious variants expected to circulate widely in the country.

“Not all adults can get the vaccine because there’s some reluctance, or there’s maybe even some vulnerable immune systems that just don’t respond,” Dr. Erbelding said. “I think we have to include children if we’re going to get to herd immunity.”

It will also be important to immunize children in racial and ethnic populations that are hit hardest by the pandemic, she added.

Abhinav, 12, a participant in the Pfizer vaccine trial at Cincinnati Children’s Hospital last month.
Abhinav, 12, a participant in the Pfizer vaccine trial at Cincinnati Children’s Hospital last month.Credit…Cincinnati Children’s Hospital

Pfizer and Moderna’s clinical trials in adults each enrolled about 50,000 participants. They had to be that large in order to show significant differences between the volunteers who received a vaccine and those who got a placebo. But because it is rarer for children to become seriously ill with Covid-19, that kind of trial design in children would not be feasible, because it would require many more participants to show an effect.

Instead, the companies will look at vaccinated children for signs of a strong immune response that would protect them from the coronavirus.

The Pfizer-BioNTech vaccine was authorized in December for anyone 16 and older. The company has continued its trial with younger volunteers, recruiting 2,259 adolescents from 12 to 15 years of age. Teenagers are roughly twice as likely to be infected with the coronavirus as younger children, according to the Centers for Disease Control and Prevention.

Results from that trial should be available by summer, said Keanna Ghazvini, a spokeswoman for Pfizer.

“Moving below 12 years of age will require a new study and potentially a modified formulation or dosing schedule,” Ms. Ghazvini said. Those trials will most likely start later in the year, but the plans will be made final after the company has data from older children, she added.

Moderna’s vaccine, which was also authorized in December, is on a similar track for pediatric testing. In December, the company began testing adolescents ages 12 through 17, and plans to enroll 3,000 volunteers in this age group. The company expects results “around midyear 2021,” said Colleen Hussey, a spokeswoman for Moderna.

Based on the results, Moderna plans to assess the vaccine later this year in children between the ages of 6 months and 11 years.

Infants may have some antibodies at birth from vaccinated or infected mothers, but that maternal protection is unlikely to last through the first year of age. And with their relatively weak immune systems, babies might be particularly susceptible to infection if community transmission is high.

The trials will also assess the vaccine’s safety in children — and hopefully ease any fears that parents have. One-third of adults in the United States have said they do not plan to have their children immunized against the coronavirus, according to a recent poll conducted by Verywell Health.

Given the low risk of Covid-19 in children, some parents might be skeptical of the urgency to inoculate their children with a brand-new jab, Dr. Offit said. “For that reason, the vaccine would have to be held to a very high standard of safety,” he said.

More than 42 million people in the United States have been immunized so far, with few lasting side effects. And the F.D.A. has set up multiple systems to carefully monitor any serious reactions to the vaccine.

“They’re really looking at the data very, very closely,” Dr. Oliver said. “As a pediatrician and a mom, I have really good confidence that those systems work.”

Once a vaccine for children is available, schools can reintroduce extracurricular activities that involve close contact, like band practice, team sports and choir. But in the meantime, there is ample evidence that schools can reopen with other precautions in place, Dr. Oliver said.

“I don’t think we need to anticipate having a vaccine in order to open schools in the fall,” she said. “We should be planning now for opening schools.”

Dr. Oliver also urged parents to make sure children are immunized for other diseases. According to the C.D.C., orders for non-flu childhood vaccines through the Vaccines for Children Program are down approximately 10.3 million doses over all.

“Now’s the time to really catch up on missed doses of those vaccines,” she said. “Measles, HPV, tetanus boosters, pertussis boosters — all of that is really important.”

Which Covid Vaccine Should You Get? Experts Weigh the Effect Against Severe Disease

Which Covid Vaccine Should You Get? Experts Cite the Effect Against Severe Disease

Infectious disease doctors say getting a shot of the J&J vaccine, which has a lower efficacy against the virus than other vaccines, would still be well worthwhile.

Covid vaccinations in Santa Barbara County, Calif., this week.
Covid vaccinations in Santa Barbara County, Calif., this week.Credit…Daniel Dreifuss for The New York Times

  • Jan. 29, 2021, 5:32 p.m. ET

At first glance, the results reported on Friday from the long-awaited trial of Johnson & Johnson’s coronavirus vaccine might have seemed disappointing. Its overall efficacy — the ability to prevent moderate and severe disease — was reported at 72 percent in the United States, 66 percent in Latin American countries and 57 percent in South Africa.

Those figures appear far below the high bar set by Pfizer-BioNTech and Moderna, the first two vaccines authorized for emergency use in the United States, which reported overall efficacy from 94 to 95 percent.

Dr. Anthony S. Fauci, the nation’s leading infectious disease expert and now the lead medical adviser to President Biden on the coronavirus pandemic, acknowledged the striking difference at a briefing on Friday.

“If you woke up and you say, ‘Well, go to the door on the left and you get 94 or 95 percent, go to the door on the right and you get 72 percent,’ which door do you want to go to?” he asked.

But Dr. Fauci said that the more crucial measure was the ability to prevent severe disease, which translates to keeping people out of the hospital and preventing deaths. And that result, for Johnson & Johnson, was 85 percent in all of the countries where it was tested, including South Africa, where a rapidly spreading variant of the virus had shown some ability to elude vaccines.

More important than preventing “some aches and a sore throat,” Dr. Fauci said, is to fend off severe disease, especially in people with underlying conditions and in older adults, who are more likely to become seriously ill and to die from Covid-19.

“If you can prevent severe disease in a high percentage of individuals, that will alleviate so much of the stress in human suffering and death in this epidemic that we’re seeing, particularly now,” Dr. Fauci said, “as we well know, over the last several weeks, our health care system has been stressed by the number of people that require hospitalization, as well as intensive care.”

Dr. Francis Collins, director of the National Institutes of Health, compared the ability to prevent severe disease to the effects of flu shots, which do not always prevent influenza entirely but can make it less severe.

“The same thing seems to be applying here, in a circumstance where this variant is clearly making it a little tougher to get the most vigorous response that you would want to have,” Dr. Collins said. “But still, for severe disease, it’s looking really good.”

The Moderna vaccine also showed high efficacy, 100 percent, against severe disease. The Pfizer-BioNTech one appeared to as well, but the overall number of severe cases in the study was too small to be sure.

But researchers warn that trying to compare effectiveness between new studies and earlier ones may be misleading, because the virus is evolving quickly and to some extent the trials have studied different pathogens.

A participant in the Johnson & Johnson vaccine trial in Cape Town, South Africa, last month.
A participant in the Johnson & Johnson vaccine trial in Cape Town, South Africa, last month.Credit…Joao Silva/The New York Times

“You have to recognize that Pfizer and Moderna had an advantage,” Dr. William Schaffner, an infectious disease expert at Vanderbilt University, said in an interview. “They did their clinical trials before the variant strains became very apparent. Johnson & Johnson was testing its vaccine not only against the standard strain but they had the variants.”

The best way to stop the spread of mutants and to prevent more new ones from emerging is to vaccinate as many people as quickly as possible, Dr. Fauci and other researchers say. Viruses cannot mutate unless they are replicating, and they cannot replicate unless they can get into cells. Keeping them out by immunizing people can shut down the process.

In addition to the Pfizer-BioNTech and Moderna vaccines already in use in the United States, three more may soon become available: those made by Novavax, Johnson & Johnson and AstraZeneca. AstraZeneca’s vaccine has already been authorized in Britain and other countries.

Globally, the Johnson & Johnson vaccine is expected to play an important role, especially in low and middle-income countries, because it works after just one shot, is relatively inexpensive and is easier to store and distribute than the vaccines made by Pfizer-BioNTech and Moderna since it does not share their stringent requirements for freezing and refrigerating.

People waiting to be vaccinated may wonder if they will be able to pick and choose among vaccines, and if they should hold out and wait until the one that looks best to them becomes available.


Covid-19 Vaccines ›


Answers to Your Vaccine Questions

Currently more than 150 million people — almost half the population — are eligible to be vaccinated. But each state makes the final decision about who goes first. The nation’s 21 million health care workers and three million residents of long-term care facilities were the first to qualify. In mid-January, federal officials urged all states to open up eligibility to everyone 65 and older and to adults of any age with medical conditions that put them at high risk of becoming seriously ill or dying from Covid-19. Adults in the general population are at the back of the line. If federal and state health officials can clear up bottlenecks in vaccine distribution, everyone 16 and older will become eligible as early as this spring or early summer. The vaccine hasn’t been approved in children, although studies are underway. It may be months before a vaccine is available for anyone under the age of 16. Go to your state health website for up-to-date information on vaccination policies in your area

You should not have to pay anything out of pocket to get the vaccine, although you will be asked for insurance information. If you don’t have insurance, you should still be given the vaccine at no charge. Congress passed legislation this spring that bars insurers from applying any cost sharing, such as a co-payment or deductible. It layered on additional protections barring pharmacies, doctors and hospitals from billing patients, including those who are uninsured. Even so, health experts do worry that patients might stumble into loopholes that leave them vulnerable to surprise bills. This could happen to those who are charged a doctor visit fee along with their vaccine, or Americans who have certain types of health coverage that do not fall under the new rules. If you get your vaccine from a doctor’s office or urgent care clinic, talk to them about potential hidden charges. To be sure you won’t get a surprise bill, the best bet is to get your vaccine at a health department vaccination site or a local pharmacy once the shots become more widely available.

Probably not. The answer depends on a number of factors, including the supply in your area at the time you’re vaccinated. Check your state health department website for more information about the vaccines available in your state. The Pfizer and Moderna vaccines are the only two vaccines currently approved, although a third vaccine from Johnson & Johnson is on the way.

That is to be determined. It’s possible that Covid-19 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. To determine this, researchers are going to be tracking vaccinated people to look for “breakthrough cases” — those people who get sick with Covid-19 despite vaccination. That is a sign of weakening protection and will give researchers clues about how long the vaccine lasts. They will also be monitoring levels of antibodies and T cells in the blood of vaccinated people to determine whether and when a booster shot might be needed. It’s conceivable that people may need boosters every few months, once a year or only every few years. It’s just a matter of waiting for the data.

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.

If you have other questions about the coronavirus vaccine, please read our full F.A.Q.

Dr. Paul Offit, a vaccine expert at Children’s Hospital of Philadelphia, told CNN that if there was an abundant supply of the Pfizer-BioNTech and Moderna vaccines, they would be his first choices because of their higher overall efficacy.

But for now, there is not enough of those vaccines.

If he could not get either the Pfizer-BioNTech vaccine or the Moderna one, he would take the Johnson & Johnson shot, Dr. Offit said — as long as the data that the company will be presenting to the Food and Drug Administration looks as good as what the company reported on Friday.

He said Johnson & Johnson’s report of the reduction in severe disease was a powerful selling point.

“That’s what you want,” Dr. Offit said. “You want to stay out of the hospital, and stay out of the morgue.”

He noted that the company was also studying a two-shot regimen, which might raise its efficacy.

People who take the Johnson & Johnson vaccine should be able to safely receive a Pfizer-BioNTech or Moderna vaccine later if a booster shot is needed, he said.

Dr. Schaffner said he had just attended a meeting with other public health experts, and they had asked one another what they would tell their spouses or partners to do if they could get the Johnson & Johnson vaccine tomorrow, or had to wait three weeks for Pfizer-BioNTech’s or Moderna’s.

“All of us said, ‘Get the one tomorrow,’” Dr. Schaffner said. “The virus is bad. You’re risking three more weeks of exposure as opposed to getting protection tomorrow.”

He said Johnson & Johnson’s 85 percent efficacy against severe disease was a bit lower than those reported by Moderna and Pfizer-BioNTech, “but it’s still pretty darn high.”

It is not yet known whether it would be safe to take one type of vaccine now and then another later, Dr. Schaffner said, adding, “We haven’t studied this.”

Johnson & Johnson’s Vaccine Offers Strong Protection but Fuels Concern About Variants

Johnson & Johnson’s Vaccine Offers Strong Protection but Fuels Concern About Variants

The vaccine’s efficacy rate dropped from 72 percent in the United States to just 57 percent in South Africa, where a highly contagious variant is driving most cases.

A dose of Johnson & Johnson’s vaccine candidate was prepared at the Rocky Mountain Regional VA Medical Center in Aurora, Colo., last month.
A dose of Johnson & Johnson’s vaccine candidate was prepared at the Rocky Mountain Regional VA Medical Center in Aurora, Colo., last month.Credit…Michael Ciaglo/Getty Images
  • Jan. 29, 2021, 8:00 a.m. ET

Johnson & Johnson announced on Friday that its one-dose coronavirus vaccine provided strong protection against Covid-19, potentially offering the United States a third powerful tool in a desperate race against a worldwide rise in virus mutations.

But the results came with a significant cautionary note: The vaccine’s efficacy rate dropped from 72 percent in the United States to 57 percent in South Africa, where a highly contagious variant is driving most cases. Studies suggest that this variant also blunts the effectiveness of Covid vaccines made by Pfizer-BioNTech, Moderna and Novavax. The variant has spread to at least 31 countries, including the United States, where two cases were documented this week.

Johnson & Johnson said that it planned to apply for emergency authorization of the vaccine from the Food and Drug Administration as soon as next week, putting it on track to receive clearance later in February.

“This is the pandemic vaccine that can make a difference with a single dose,” said Dr. Paul Stoffels, the chief scientific officer of Johnson & Johnson.

The company’s announcement comes as the Biden administration is pushing to immunize Americans faster even with a tight vaccine supply. White House officials have been counting on Johnson & Johnson’s vaccine to ease the shortfall. But the company may only have about seven million doses ready when the F.D.A. decides whether to authorize it, according to federal health officials familiar with its production, and about 30 million doses by early April.

The variant from South Africa, known as B.1.351, could make things even worse for the vaccine push. Given the speed at which the variant swept through that country, it is conceivable that by April it could make up a large fraction of infections in the United States. That would undermine the effectiveness of available vaccines.

The fact that four vaccines backed by the federal government seem to be less effective against the B.1.351 variant has unsettled federal officials and vaccine experts alike. Facing this uncertainty, many researchers said it was imperative to get as many people vaccinated as possible — quickly. Lowering the rate of infection could thwart the contagious variants while they are still rare, and prevent other viruses from gaining new mutations that could cause more trouble.

“If ever there was reason to vaccinate as many people as expeditiously as we possibly can with the vaccine that we have right now, now is the time,” Dr. Anthony S. Fauci, the government’s top infectious disease expert, said in an interview. “Because the less people that get infected, the less chance you’re going to give this particular mutant a chance to become dominant.”

As the United States scrambles to get enough vaccines, the country is turning into something of an evolutionary experiment. The B.1.351 variant is one of several that have arrived in the country or originated here, all with the ability to spread faster than other variants.

“The pandemic is a lot more complicated now than it was a couple months ago,” said Dr. Dan Barouch, a virologist at Beth Israel Medical Center in Boston.

Vaughan Cooper, an evolutionary biologist at the University of Pittsburgh, said that all the new variants were likely evolving quietly for months before bursting on the scene. “I think we’re going to see many stories like this,” he said.

Federal regulators are also still waiting on data from Johnson & Johnson’s new manufacturing facility in Baltimore that prove it can mass-produce the vaccine. The company is counting on that factory to help reach its contractual pledge to the federal government of 100 million doses by the end of June.

If Johnson & Johnson can deliver vaccines quickly enough to the United States, it might be able to help drive down cases before variants make things worse. Since the vaccine requires only a single shot — unlike the Moderna and Pfizer-BioNTech vaccines, which require two — that delivery would translate into full coverage for 100 million people.

Johnson & Johnson’s vaccine has another advantage that might help speed up the rollout. It can stay viable in a refrigerator for three months, while the two authorized vaccines have to be kept frozen. That gives the company an edge not just in reaching more isolated parts of the United States, but in getting the vaccine to remote areas of the world that could otherwise seed more aggressive mutants.

“If you talk about the potential impact on the developing world, I believe it’s much more relevant than here,” Dr. Fauci said.

But vaccine makers also have to prepare for the B.1.351 variant or another one surging to dominance and demanding new vaccines. “You’ve got to be nimble enough to be able to adapt by upgrading our vaccines that match the dominant strain,” Dr. Fauci said.

Exactly when to make that switch will be a difficult decision, because the viruses are spreading unpredictably, and manufacturing new doses will be a huge undertaking.

“The implications of that are big. You would not take that choice lightly,” said John D. Grabenstein, an epidemiologist with the Immunization Action Coalition, a nonprofit organization that disseminates information about vaccines. “It’s not doomsday. It’s just that we are going to need a bigger boat.”

Johnson & Johnson’s announcement came one day after Novavax said an early analysis of its 15,000-person trial in Britain had revealed that the two-dose vaccine had an efficacy rate of nearly 90 percent there. But in a small trial in South Africa, the efficacy rate dropped to just under 50 percent.

Johnson & Johnson presented only a summary of findings of its clinical trial. The vaccine was 85 percent effective in preventing severe disease in all three regions where the trial was run: the United States, Latin America and South Africa. After 28 days, none of the vaccinated participants who developed Covid-19 had to be hospitalized.

The company reported that the vaccine’s protective effect seems to increase with time. But without long-term data on immunity, scientists and regulators do not yet know whether the vaccine’s efficacy peaks at some point before dropping.

Dr. Stoffels said the company was still waiting for more data on whether the vaccine can protect against asymptomatic infection.


Covid-19 Vaccines ›


Answers to Your Vaccine Questions

Currently more than 150 million people — almost half the population — are eligible to be vaccinated. But each state makes the final decision about who goes first. The nation’s 21 million health care workers and three million residents of long-term care facilities were the first to qualify. In mid-January, federal officials urged all states to open up eligibility to everyone 65 and older and to adults of any age with medical conditions that put them at high risk of becoming seriously ill or dying from Covid-19. Adults in the general population are at the back of the line. If federal and state health officials can clear up bottlenecks in vaccine distribution, everyone 16 and older will become eligible as early as this spring or early summer. The vaccine hasn’t been approved in children, although studies are underway. It may be months before a vaccine is available for anyone under the age of 16. Go to your state health website for up-to-date information on vaccination policies in your area

You should not have to pay anything out of pocket to get the vaccine, although you will be asked for insurance information. If you don’t have insurance, you should still be given the vaccine at no charge. Congress passed legislation this spring that bars insurers from applying any cost sharing, such as a co-payment or deductible. It layered on additional protections barring pharmacies, doctors and hospitals from billing patients, including those who are uninsured. Even so, health experts do worry that patients might stumble into loopholes that leave them vulnerable to surprise bills. This could happen to those who are charged a doctor visit fee along with their vaccine, or Americans who have certain types of health coverage that do not fall under the new rules. If you get your vaccine from a doctor’s office or urgent care clinic, talk to them about potential hidden charges. To be sure you won’t get a surprise bill, the best bet is to get your vaccine at a health department vaccination site or a local pharmacy once the shots become more widely available.

Probably not. The answer depends on a number of factors, including the supply in your area at the time you’re vaccinated. Check your state health department website for more information about the vaccines available in your state. The Pfizer and Moderna vaccines are the only two vaccines currently approved, although a third vaccine from Johnson & Johnson is on the way.

That is to be determined. It’s possible that Covid-19 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. To determine this, researchers are going to be tracking vaccinated people to look for “breakthrough cases” — those people who get sick with Covid-19 despite vaccination. That is a sign of weakening protection and will give researchers clues about how long the vaccine lasts. They will also be monitoring levels of antibodies and T cells in the blood of vaccinated people to determine whether and when a booster shot might be needed. It’s conceivable that people may need boosters every few months, once a year or only every few years. It’s just a matter of waiting for the data.

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.

If you have other questions about the coronavirus vaccine, please read our full F.A.Q.

The company is preparing a lengthy briefing document it will submit to the F.D.A. in its application for authorization. The agency’s scientists will review the raw data from the trial and present their own analysis.

Unlike the messenger RNA vaccines made by Pfizer-BioNTech and Moderna, Johnson & Johnson uses an adenovirus, which normally causes the common cold. While adenovirus-based vaccines have been investigated for some three decades, they have yet to be licensed for use in the United States.

Johnson & Johnson’s Ebola vaccine became the first approved adenovirus-based vaccine for any disease when European regulators gave it the green light last July. Astra-Zeneca and the University of Oxford used a different adenovirus for their coronavirus vaccine, which is now authorized in Britain and other countries. Russian scientists created their Sputnik V vaccine from adenoviruses as well.

Johnson & Johnson received $456 million from Operation Warp Speed to support its research. In July, the government agreed to purchase 100 million doses for $1 billion if it proved safe and effective.

That same month, the company moved into clinical trials, which found that a single shot produced a strong immune response, consistent with experiments done on monkeys. Johnson & Johnson began the final “Phase 3” trial in September, again using a single dose. It recruited volunteers in the United States, South Africa and Latin America.

Half of the volunteers received the vaccine, and half received a placebo. The company then had to wait. Only when enough people in the trial got Covid-19 would an independent board of advisers look at the results to see how many sick volunteers were vaccinated — a process known as unblinding.

Late last year, surges of coronavirus infections accelerated the trial toward unblinding. In December, Johnson & Johnson decided it would not need to recruit 60,000 volunteers as it originally planned. It capped the trial at 45,000.

Like other vaccine developers, Johnson & Johnson was required by the F.D.A. to also record information about adverse events experienced by the volunteers for the first few months after vaccination.

Dr. Barouch, who led the team that designed the vaccine and tested it on animals last year, had to wait for months for the unblinding. “I’m thinking a lot about it,” he said in a Jan. 11 interview. “But, no, I don’t have champagne ready to go.”

After he learned the results, Dr. Barouch said he was delighted. “I think this vaccine will have a public health benefit throughout the world,” he said.

Johnson & Johnson is also moving forward with other trials of the vaccine to see how it can be improved. In December it began a trial with two doses. Dr. Fauci was optimistic that people who get a so-called prime boost may enjoy even more protection.

“If they get a prime boost, it’s entirely conceivable that they can get up to 90-plus percent,” he said.

In addition, Dr. Stoffels said that Johnson & Johnson was tailoring a version of its vaccine with a protein patterned after the B.1.351 variant. It could potentially deploy it in countries where that version of the virus was a threat.

“Pretty much all vaccine developers now are having that conversation,” said Dr. Peter J. Hotez, a vaccine expert with the Baylor School of Medicine and the creator of a different coronavirus vaccine.