Tagged Coughs

Think Like a Doctor: A Cough That Won’t Stop Solved!

Photo

Credit Andreas Samuelsson

On Thursday we asked Well readers to unravel the case of a middle-aged man who had a cough for over a year. He was just about to give up on finding a cause or cure when he started coughing up blood. A CT scan done at that point revealed a strange hole near the base of the right lung. Your challenge was to figure out what was going on.

The correct diagnosis is:

An aspiration of a foreign body

Over 400 of you wrote in and a handful of you figured it out. Anne Hartley was the first to suggest that the man inhaled a foreign object. She’s a general internist at Rush Medical College in Chicago. When I asked her how she figured it out she said it was easy. She has two small children and so, she told me, “foreign bodies are always on my mind.” Reading how healthy the patient appeared made it seem even more likely that he had accidentally inhaled something that was now lodged in his lungs. Strong work, Anne!

So he had inhaled something – but what? A couple of you even figured that out. A shout out to Toni Brisby of Britain, who was the first to suspect that the patient had inhaled a seed. Well done, Toni!

The Diagnosis:

The first successful removal of an aspirated object was published in 1897. A small bone was retrieved from the airways of a German farmer using a long metal tube and a set of tweezers. At that time, half of all people who accidentally aspirated objects into their lungs died. That changed dramatically over the next decades when an American ear, nose and throat specialist developed early versions of the tools used to remove such objects. That doctor, Chevalier Jackson, devoted his life to putting these tools to use. A collection of the several thousands objects he retrieved from airways of the children and adults who needed him is on display at the Mütter Museum in Philadelphia.

These days foreign body aspiration is most common in boys between the ages of 1 and 2. The mortality rate is 7 percent in children younger than 4. Only a tiny fraction of aspirations (well under 1 percent) occur in adults, and most of those adults are either elderly or have some underlying condition that makes swallowing difficult – because of some neurological problem, like having a stroke, or because they are impaired by alcohol or drugs. What is aspirated also varies with age. In children, most of the aspirated objects are nuts or seeds.

In adults the most common objects fished out of the lungs were pins or small plastic objects. Foods were a distant second. Most adults sought medical care within 24 hours but some didn’t remember aspirating at all and others remembered only once the object was found, when a bronchoscopy was done to evaluate symptoms – as was the case here. Persistent cough was the most common symptom but recurrent infections were also seen. Presence of the object was often suspected from chest X-rays, which sometimes showed air trapping in the lung beyond the obstruction.

How the Diagnosis Was Made:

Dr. Karen Schmitz was the doctor caring for the 43-year-old man, who went to the hospital after two weeks of coughing up blood (hemoptysis) – the newest development in a cough that had lasted a year and a half. A CT scan showed a strange hole in the lower part of his right lung. Because tuberculosis could cause such holes as well as hemoptysis, he was in an isolation room until the doctors were sure he didn’t have it.

Still, TB seemed an unlikely diagnosis. He had never been exposed to TB and had no real risk factors. And even though he had an impressive cough, none of the usual symptoms of TB were present. He had no fever or night sweats, hadn’t lost weight, and he didn’t feel sick. So even before the tests came back the question became, if it wasn’t TB, what was causing this cough?

He was seen by an infectious disease specialist and Dr. Timothy Clark, a lung specialist. They agreed on the most likely culprits. It could be some kind of fungus – chronic fungal infections can cause few or even no symptoms. He had traveled in Southern California and Arizona, both places where a fungus called Coccidioides often caused asymptomatic disease. Blood tests were ordered to look for common fungi. There was also the possibility that it might be something worse – a lung cancer. Again he had no risk factors – he’d never smoked – but it was a possibility. So doctor and patient decided that the best course of action would be for the pulmonologist to look directly into the patient’s lungs. The test, called a bronchoscopy, was scheduled for the following morning.

The Doctor Is Surprised:

Early the next day the patient was taken to a procedure room to have his bronchoscopy. In this test a tiny camera is threaded into the lungs to look at the lesion using the CT scan to help navigate to the right spot.

The patient was lightly sedated, and moments later Dr. Clark inserted the scope. The lung specialist guided the instrument down the narrow pink corridors of the airways. The goal was to get as close as possible to the hole seen on the scan and take samples of the surrounding tissues. Suddenly the doctor stopped. He saw something – was it a tiny piece of metal? – sitting where the airway forked. He edged the scope a little closer. It was black and smooth with a shape that was strangely familiar. He threaded a tiny gripper through the scope, onto the end next to the camera, and pulled the object out.

“Is that a seed?” he asked. Suddenly the patient said in a slurred voice, “It’s a sunflower seed.” Dr. Clark dropped the tiny object into a specimen cup. “You’re right! It is a sunflower seed!”

Even under the influence of the sedative, the patient was able to remember when he’d inhaled the seed. It was at a baseball game he’d gone to with his older son. He’d bought a bag of sunflower seeds – his favorite snack — and was cracking them open with his teeth when suddenly one seed escaped and went down the wrong pipe. He started coughing immediately as his body fought to expel the foreign object. He coughed for what seemed to be a long time and while he never felt the seed come up, the spasm finally subsided. And he felt fine. He didn’t really think about it again until a couple of weeks later when he started coughing again. He told his first couple of doctors about it, but they pooh-poohed the notion. The interval between the choking event and the onset of the cough made aspiration much less likely. Besides, it’s usually only a problem for the very young or the very old — rarely for the perfectly healthy middle-aged guy.

Did the doctor think that this little seed could account for the coughing that had been killing him for the past 18 months? The doctor nodded. And if it was, he should get better within a couple of days.

The patient was ecstatic. Maybe it was just the relief of knowing that his 18 months of coughing were over or maybe it was the drugs they’d given him for the procedure, but the exuberant man found himself calling out as he was wheeled out the elevator to his hospital room: “Yay, I don’t have cancer. Yay, it was a seed.” He shook the cup with the retrieved seed in time with his chant.

As they watched the man roll out of the procedure room Dr. Clark turned to Dr. Schmitz. “You know I’ve seen this one other time. And it’s funny – we always forget to think of it.”

That was last December. After a couple of days, the cough was completely gone. And once baseball season started this spring, the man was able to enjoy his sunflower seeds just as he always had.

Think Like a Doctor: A Cough That Won’t Stop

Photo

Credit Andreas Samuelsson

The Challenge: A 43-year-old man starts to cough every time he takes a deep breath. Can you help him figure out why?

Every month, the Diagnosis column of The New York Times Magazine asks Well readers to try their hand at solving a medical mystery. Below you will find the story of a healthy middle-aged man who starts coughing and just can’t stop. He can’t exercise. He can’t laugh. Sometimes he can’t even talk without interrupting himself with deep, awful-sounding hacks.

Below I provide much of the information available to the doctors who examined him. It took 18 months before a doctor figured out what was wrong. Can you do it any faster? The first reader to offer the correct diagnosis will receive a signed copy of my book, “Every Patient Tells a Story,” and the satisfaction of solving a real-life case.

An Emergency 18 Months in the Making

“You should probably have that checked out in the E.R.,” the nurse suggested to the middle-aged man on the other end of the phone. “And sooner rather than later.” In the next few days? he asked. In the next few hours, the nurse replied.

The 43-year-old man hung up the phone more surprised than worried. He had been dealing with an annoying and persistent cough for a year and a half and none of the doctors or nurses he’d seen in that time seemed to think it was a big deal. Until now – since he started coughing up blood.

He called his wife to tell her what the nurse suggested. After work he was going to drive himself to the emergency room at the veterans’ hospital in downtown Denver. He could hear the relief in her voice when she asked if he wanted her to come with him. No, she had enough on her hands looking after their four children. He’d let her know what they said.

An Abnormal X-ray

In the E.R., the man’s complaint got him seen right away. His chest X-ray was normal, they told him. (The X-ray is shown here)

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But when they came back into his cubby wearing masks over their noses and mouths he suspected that the CT scan was not. The scan had shown some kind of hole in his lungs, the E.R. doctor told him. That’s why he was coughing up blood. One of the diseases that can cause those kinds of cavities was tuberculosis. Had he ever been exposed to TB? Not that he knew of. (The CT scan images are shown here.)

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Because TB was such a dangerous disease – and extremely contagious — they would have to find out if he had it. If he did, he would certainly need to be treated. And to make sure he didn’t infect anyone while he was being tested, he needed to be in a specialized room – a room where the air he breathed wouldn’t be breathed by anyone else. None of the hospital’s negative pressure rooms were available so they were going to transfer him to Presbyterian/St. Luke’s Medical Center, the big regional hospital just a couple of miles away. They had an available room and would be able to care for him.

You can read the patient’s history and physical from the E.R. here:

Admission Notes

The patient’s notes from the hospital.

The Patient’s Long Story

Dr. Karen Schmitz was the second-year resident assigned to care for the new guy sent over to be tested for TB. She could see the patient sitting up in bed talking on the phone as she secured the mask over her nose and mouth and entered the double-door room that would prevent any air-borne infectives from spreading. As she entered, the patient looked at her, smiled a warm smile, and held up a finger as if to say, “I’ll be with you in a minute.” As he finished up his phone call, the doctor looked at him carefully. He was a robust guy – youthful and healthy looking. He certainly didn’t look like any of the people she’d cared for with active TB. When he hung up, he apologized and the doctor introduced herself. She pulled up a chair and settled in. She knew from what she’d read in the chart that it was going to be a long story.

The bloody cough was pretty new, he told her. It started two weeks earlier. But the cough itself had been around for 18 months. He’d caught it a couple of summers ago, and it just never went away. At first he thought it was bronchitis – he’d had that a lot when he was a kid — but when it lasted for more than a couple of weeks, he went to see his primary care doctor. He’d never had a fever or any other sign of being sick. He had some runny nose and itchy eye symptoms that started weeks before the cough and so he and his doctors thought it was allergies. Or asthma. His doctor prescribed an antihistamine and later an inhaler. They fixed his runny nose, and eased up the chest tightness, but the hacking never slowed down.

He went to an ear, nose and throat specialist who scoped his nose and throat. Completely normal. He had a chest X-ray – also normal.

He saw a pulmonologist who, hearing that he had a little heartburn, started him on a powerful antacid medication. That pill completely fixed the heartburn but didn’t touch the cough.

That first year he’d seen three doctors in a half-dozen appointments, and had a scope, a chest X-ray and a slew of blood tests and still no one could tell him why he was coughing or how to make it stop. So he figured he’d just have to learn to live with it.

Not that he wanted that. Every time he took a deep breath he would cough. In the middle of telling a good story he’d have to stop to cough. Whenever he laughed, he coughed. Dozens of times a day, he coughed. He even had to give up exercising. Any time he exerted himself, even just a little, the cough would kick in with a shocking fierceness. Recently he’d tried riding his bike and just 15 minutes in he had to stop. Even though he was taking it easy, as soon as he started to breathe just a little harder than usual, he nearly keeled over. He had to get off his bike. He was doubled over with the ferocious hacking. Sweat and tears poured down his cheeks. He could hear the rasping sound of his breath between the deep jagged coughs. He wondered if he could even make it home. That was the last time he tried to exert himself. And that had been weeks earlier.

You can see the pulmonologist’s notes here:

Pulmonary Consult Note

The notes from the lung specialist.

The Doctor’s Visit

But eventually, he started to cough up blood. That happened the morning after he’d had another terrible blast of coughing. He’d gone with his wife and four children to Vail for Thanksgiving. As he was packing the car to come home he started coughing and felt as if it would never stop, as if he’d never be able to breathe again. But he recovered, until the next morning when he started to cough up blood. It scared him. And terrified his wife. When it didn’t get better after a couple of weeks, he’d decided to call the hospital, and the nurse on the phone sent him to the E.R.

Now, talking to Dr. Schmitz, he told her he never smoked and rarely drank. And even though it was legal, he never smoked pot either. He had been an officer in the Air Force and now was a real estate agent. He had spent a few months in Kuwait and another few in Saudi Arabia, but that was in the 1990s. He’d traveled a bit – mostly out west, but nothing recent. He took medicine for high cholesterol, the antihistamine and the antacid medicine, but that was it. His exam was unremarkable. Dr. Schmitz listened hard through her stethoscope as she placed it on his chest where she knew the hole in his lung was, but heard nothing abnormal.

She didn’t start him on antibiotics, because she didn’t yet know what she was treating, she told him. Tuberculosis seemed unlikely so she was going to test him for other infections as well. To make sure the team didn’t miss anything, they consulted an infectious diseases specialist and a pulmonologist.

You can see their notes here.

Infectious Disease Consult

Notes from the infectious disease specialist.

Dr. Schmitz checked on her patient throughout the day. He was always on the phone, his computer open, hard at work. So far they were doing nothing for the guy – just watching and waiting for answers. When the TB test came back negative, Dr. Schmitz thought he might very well be the healthiest patient in the entire hospital. Was she right? The patient got his diagnosis the very next day.

Solve the Mystery

What do you think is making this patient cough?

Post your answers in the comment section. I’ll tell you the answer tomorrow.

Think Like a Doctor: The Tired Gardener

The Challenge: Can you figure out what is wrong with a lively 67-year-old gardener who develops a daily fever and shaking chills along with chest pain and a dry cough?

Every month, the Diagnosis column of The New York Times Magazine asks Well readers to solve a real-life diagnostic mystery. Below you will find the details of a case involving a retired maker of surgical supplies who starts having daily fevers along with chills, chest pain and a dry cough.

I’ll give you the same information the doctor was given before he made this diagnosis. Will you be able to figure out what’s wrong?

As usual, the first reader to submit the correct diagnosis gets a signed copy of my book, “Every Patient Tells a Story,” and the pleasure of puzzling out a tough but fascinating case.

The Patient’s Story

“NoNo says he doesn’t feel good,” the 9-year-old girl said of her grandfather, handing her mother the thermometer. The woman dried her hands on her apron and took the device. She squinted at the little electronic numbers. Just under 102 degrees.

Her father had been sick for weeks. Feverish, weak, not eating. It was late summer and the tomatoes and eggplants in the garden were ripe, but he hadn’t even walked through his garden for days, so she knew he wasn’t feeling well. But this was the first time he’d admitted that something more serious might be going on.

It was about time. She’d taken her 67-year-old father to several doctors over the past two months. They’d looked him over and given him antibiotics, but it hadn’t helped.

“Tell NoNo that if he’s feeling sick he’s got to go to the hospital,” she told the little girl. She darted back to her grandfather’s room then quickly returned. “He says he’s ready to go.”

The woman wasn’t sure exactly when her father had started to get sick, but six or seven weeks earlier she had noticed that he was no longer the first one out of bed. Instead of being up and out before 7 a.m., he wouldn’t get up until late morning. And he started to have strange shaking chills each afternoon and evening, followed by a fever — regular as clockwork.

He looked sweaty and pale. She asked him what was wrong, but he said he was fine. Or sometimes he’d say he felt a little tired. After an hour or two the fever would pass and he’d just look tired, but the next day, or sometimes the day after, the fever would be back.

The First Diagnosis

The woman first took her father to his regular doctor. Knowing how much he loved to work in his garden, the doctor figured he probably had Lyme disease. It was summertime, and Lyme was common in the area of Connecticut where they lived. Plus, he practically took root in the half-acre garden back behind the house where he lived with his wife and their children and grandchildren.

This was the first summer the woman could remember where her father wasn’t out in his garden every single day. This year it seemed that whole weeks would go by when he did nothing but look out the window at his beautiful handiwork.

Her father took antibiotics for the presumed Lyme. It didn’t help.

A Second Diagnosis

When the patient went for a follow-up visit, he told his doctor that his stomach was bothering him a bit. So he was referred to a gastroenterologist. That doctor diagnosed Helicobacter pylori – a bacterium tough enough to survive the acid environment of the stomach that can cause pain and ulcers.

He took two weeks of treatment for that — three medications to kill the bug, and one to neutralize the acid they thrive in. That didn’t stop the daily fevers, either.

Recently the man’s wife noticed that he’d developed a dry cough. Was this a pneumonia? His doctor gave him yet another antibiotic. And he was still taking that pill when he agreed to go to the emergency room.

Pneumonia?

So three generations — wife, daughter and granddaughter — got in the car with the man they loved and drove to the hospital where the daughter worked.

The emergency room was quiet when they arrived, and after explaining that the patient had been having fevers for weeks, the patient and his entourage were taken into the back so he could be seen right away.

He did have a fever but otherwise looked pretty healthy. The doctors there seemed to focus on the cough and fever. They figured he had a pneumonia that wasn’t responding to the antibiotics he was taking. And when a chest X-ray failed to show any sign of pneumonia at all, the doctors sent him home.

You can see the note from that first visit to the Emergency Department here.

First ER Visit

If Not Pneumonia, Then What?

The next day, the man felt no better. His daughter was distressed. Her father was sick. Antibiotics weren’t working. And he was getting worse.

She called his primary care doctor again. He was also worried, he told her. But he didn’t know what to suggest.

What if she tried a different emergency room?, she suggested. They had gone to Yale-New Haven Hospital initially because that’s where she worked, but what if they went to the smaller branch of the hospital, St. Raphael’s Hospital, less than a mile away. They had different doctors there, and the hospital had a different feel — local and friendly rather than big and academic. Maybe they would find a doctor there who could help them figure out what was going wrong. It was unorthodox, the doctor told her, to shop around emergency rooms. And it wasn’t clear what another E.R. visit might do. But he was also worried about the patient, and it was certainly worth a try.

Another E.R. Visit

So early that evening they all got back into the car and drove to the St. Raphael campus. The E.R. was bustling when the family came in. Once again he had a fever – 101.6 degrees. His family explained how sick he’d been, how tired. And yet when the doctor examined him, he seemed well enough. He couldn’t find anything abnormal beyond the fever.

The labs told a slightly different story. His red blood cell count was low. So were his platelets – a type of blood cell that helps blood to clot. What was particularly strange was that these two findings had been checked the day before at the other E.R. and had been fine. And there was some evidence that he had some liver damage.

And when tested for viral hepatitis — a common causes of abnormal liver tests — he tested positive for hepatitis A and possibly hepatitis B as well.

He was admitted to St. Raphael’s Hospital because of his worsening anemia and viral hepatitis.

You can see the note from this second emergency room visit, and the admission note from the night team here.

The Second ER Note

Admission Note

Fitting the Pattern

The next morning, Dr. Neil Gupta saw the patient. Hearing the patient’s story, and the diagnosis of hepatitis A infection, was a little puzzling. Patients with hepatitis usually have mild flu-like symptoms, with a loss of appetite, nausea and vomiting, plus fatigue, low-grade fever and a generalized sense of being unwell. Certainly this patient didn’t feel well, but he had no nausea, no vomiting. And his fever came in spikes. The pattern didn’t really match.

Dr. Gupta sat down with the patient’s family and reviewed all the symptoms and the timeline. Then he reviewed all the labs. He sent off a bunch of tests.

You can see Dr. Gupta’s note here.

The Doctor’s Note

Solving the Mystery

Dr. Gupta was finally able to figure out what was wrong with this man. Can you?

The first person to figure out what is really going on with this 67-year-old gardener gets a copy of my book and that lovely sense of satisfaction that comes from making a tough diagnosis.

Rules and Regulations: Post your questions and diagnosis in the comments section below. The winner will be contacted. Reader comments may also appear in a coming issue of The New York Times Magazine.

Why Pertussis is Making a Comeback

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Credit Getty Images

Whooping cough, a potentially life-threatening childhood illness, all but disappeared in the 1940s after a vaccine was developed. Why is it making a comeback now, when most children are vaccinated?

In recent years, there have been several outbreaks reaching numbers not seen since the 1950s. A spike in 2012 sickened 48,277 Americans, and 20 died, most of them infants. There were 13 deaths in 2013 and again in 2014, the last year for which statistics are available.

The respiratory illness induces such powerful, uncontrollable fits of coughing — the medical term is paroxysmal coughing — that older patients may break a rib or burst capillaries in the eyes. Children may have seizures. Babies, who cannot cough that hard, can stop breathing and die.

A recent study from California confirms what earlier reports have suggested: that the newer pertussis vaccine, reformulated to be safer and have fewer side effects than the older version, just isn’t as effective.

The study, by researchers at Kaiser Permanente’s Vaccine Study Center in Oakland, Calif., found that just three years after vaccination with the new vaccine and booster, teenagers had lost virtually all of the vaccine’s protection, and more than 90 percent were susceptible to infection four years after the booster. The teenagers had received only the newer form of the pertussis vaccine and booster, a form without whole cells called DTaP, which in the 1990s replaced the previous vaccine, a whole-cell pertussis vaccine called DTwP. (The pertussis vaccine is given in combination with those for diphtheria and tetanus.)

These teenagers had the highest incidence of pertussis of any age group in 2014, despite receiving boosters at ages 11 to 12. The booster was introduced in 2005 when health experts realized the new vaccine was not conferring lifelong protection, officials with the Centers for Disease Control and Prevention said.

But the study showed that even with the booster, teenagers were still vulnerable to infection.

“The new vaccine provides reasonable short-term protection during the first year, but the protection wanes over the next few years, and not much remains by about three years after vaccination,” said Dr. Nicola Klein, a director of the Kaiser Permanente Vaccine Study Center and lead author of the study, published in Pediatrics earlier this month.

Pertussis had never been eradicated. Having the disease does not confer lifelong immunity. But the last time there were more than 40,000 infections in the United States was in 1959. That was down from a high of more than 265,000 infections in 1934. By 1976, the number was down to 1,010 infections in the entire country.

“The levels at which it’s occurring now haven’t been seen in at least 50 years,” Dr. Klein said.

“The biggest driver is waning immunity from our vaccines,” said Tami Skoff, an epidemiologist with the division of bacterial diseases of the C.D.C. “The protection doesn’t last as long as we originally thought it would.”

Despite concerns about the effectiveness of the new vaccine, there are no plans to return to the old one. The earlier vaccine carried a high risk of alarming but temporary side effects like pain, swelling at the site of the injection and fever, as well as more serious complications like febrile convulsions or loss of consciousness, said Dr. James D. Cherry, professor of pediatrics at the David Geffen School of Medicine at U.C.L.A., who has written extensively about pertussis. There had also been cases of a brain disorder, encephalopathy, after vaccination.

“The older vaccine had some significant downsides; the new one is much better tolerated but may not be providing as robust protection,” said Dr. Wanda Filer, the president of the American Academy of Family Physicians.

That does not mean you should skip vaccinations — on the contrary: Experts say vaccinations are more important than ever for children, pregnant women, and adults generally, especially those who will be in close contact with a newborn, such as grandparents, siblings or a nanny.

Pregnant women should be vaccinated during the third trimester, the C.D.C. says, even if they have been immunized before. That way, they can develop antibodies that are passed on to the fetus through the placenta. The ideal time for mothers to get the shot is the 27th to 36th weeks of pregnancy; the protective antibodies are highest two weeks after the vaccination.

For adults, even if the vaccine does not prevent disease entirely, it reduces the severity.

That is important, Ms. Skoff said, because the disease — which once killed thousands of Americans each year — can be miserable and prolonged. It can last for months and is often called the “100-day cough.”

Making a diagnosis is tricky. Even though pertussis is a bacterial respiratory infection that responds to antibiotics, the diagnosis is usually missed early on when the condition is treatable because it is mistaken for a cold or bronchitis. Not all patients exhibit the disease’s characteristic whooping sound when they catch their breath after coughing.

“It’s a very painful disease,” said Dr. Carrie Byington, a professor of pediatrics at University of Utah who heads the American Academy of Pediatrics’ committee on infectious diseases. She had pertussis herself when she was a young doctor. “It’s not like any other cough you’ve experienced. Even as an adult, you can’t really control it. It’s incredibly powerful.”

A severe infection may require hospitalization, and recovery can take months; the illness can have a lasting effect on lung function, leaving people with shortness of breath or fatigue. Even after a person recovers, another viral respiratory infection can cause pertussislike cough spasms, doctors said.

For now, however, the focus is not on developing a more effective vaccine. Instead, public health officials are promoting vaccinations for pregnant women and adults. Some experts have suggested more frequent vaccinations for everyone, timed before an expected outbreak, or every three years.

New vaccines “are a long ways away,” Dr. Cherry said. “Until then, we’re much better off than we were in the past, and we aren’t having reactions with vaccines.”

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Whooping Cough Booster Shot May Offer Only Short-Term Protection

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The rapidly fading effectiveness of the pertussis booster vaccine may help explain recent widespread outbreaks of whooping cough.

The United States stopped using a whole-cell pertussis vaccine in the 1990s and began using an acellular version called DTaP. Five vaccinations are given during childhood, and a booster vaccine, called the Tdap, is given to adolescents and adults.

Researchers looked at 1,207 pertussis cases among children who had had the acellular vaccine in childhood. The study, in Pediatrics, found that when these children got the Tdap booster, it was 69 percent effective after the first year, then dropped to less than 9 percent two to three years later.

A new, more effective vaccine against whooping cough is needed, but according to the lead author, Dr. Nicola P. Klein, co-director of the Kaiser Permanente Vaccine Study Center, a change in schedule might be effective until one is developed.

“We need to think about whether we should have a targeted routine of vaccines instead of an age-based method,” she said. “There are a number of ways to do this. We’ve seen epidemics every four years in California, so maybe every four years would work. Or we could vaccinate whenever there is an outbreak.”

Dr. Klein added that the vaccination of pregnant women is effective in preventing pertussis in newborns, and that all pregnant women should get the Tdap vaccine in the third trimester of pregnancy.