When Immunity Fails: The Whooping Cough Epidemic
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December 16, 2010 – Thirty years ago, whooping cough had nearly disappeared. Today, it's back. The epidemic has already killed 10 babies and infected thousands of children this year in California. KPBS and the Watchdog Institute at SDSU are working together to look at who’s getting sick, facts about the vaccine, and how public health agencies have responded.
JOANNE FARYON: Hello, I’m Joanne Faryon. Welcome to tonight’s special, When Immunity Fails: The Whooping Cough Epidemic. We’ll explore the worst whooping cough outbreak in California in more than 60 years. Just why is a disease that was nearly extinct thirty years ago, finding its way back not just in this state, but in other parts of the country as well? What we learned may surprise you. There are serious questions about how well the vaccine to prevent the disease works; questions government health officials have been slow to even ask. KPBS teamed up with the Watchdog Institute, an investigative journalism center at San Diego State University, and Radio Netherlands Worldwide to tell this story. A story that took us across California and overseas to Amsterdam. But first, we begin in a delivery room in a San Diego hospital, where a mother has just given birth to her third son. [ baby crying ] Matthew Jacob Bryce was born Oct 11, 2010. A healthy baby boy, the third boy for Cindy and Marlon Bryce. Matthew started showing signs of a cold when he was just two weeks old. The Bryce family knew something was wrong. MARLON BRYCE: So it just seemed like this cold it was just affecting his breathing. FARYON: The family was aware of the whooping cough epidemic in California, from news reports REPORTER: State health officials say more than 6,400 cases of whooping cough have been reported this year. FARYON: And their pediatrician. BRYCE: There wasn’t any whooping or they always say there is a whooping or a cough, he didn’t have a cough or anything it was just that there was a cold. FARYON: Matthew’s doctor suspected it could be whooping cough, also known as pertussis. She took a nasal swab and sent it to the lab. She also started Matthew on antibiotics. Six days later, with Matthew just 23 days old, Cindy Bryce got a phone call from the California Department of Health. The diagnosis was whooping cough. M. BRYCE: The moment I heard it I just immediately started thinking the worst because you have heard the news about the babies that have passed away. FARYON: From January to October this year, 10 newborns in California died from whooping cough, two in San Diego County. More than 7,000 children and adults got sick from the disease - the highest number in the state in more than 60 years. Just how did Matthew and so many others come down with a disease that is supposed to be preventable with a vaccine? Tonight we’ll raise questions about the effectiveness of that vaccine. A four-month investigation by KPBS and the Watchdog Institute, found many people who have been diagnosed with whooping cough were immunized. We also show how government data on the number of people diagnosed with whooping cough lacks timeliness and is often inconsistent, begging the question: just who is keeping track of this epidemic? We’ll show you how some of the experts who influence vaccine policy are financially tied to vaccine companies. And, we’ll follow the Bryce family as they struggle with their son’s diagnosis, and the setbacks in his recovery. Whooping cough, violent cough, the hundred-day cough; all names for pertussis. DR. JAMES CHERRY: What causes the cough actually we don’t know… there’s no other cough quite like it. FARYON: Pertussis is a respiratory illness caused by the bacterium bordetella pertussis. At first, it can mimic a cold. But later produces a violent and persistent cough, a cough that leaves children gasping for air – creating the distinct whooping sound. For adults, whooping cough may only be a nuisance. In fact scientists estimate more than 80 percent of adult cases are never diagnosed because most people assume they just have a bad cold. But to infants whooping cough can be deadly, especially if not diagnosed early. DR. JAMES CHERRY: So with infection that you eventually clear the bacteria and you get better. But it's a prolonged, a good percentage of cases will last one or two months. DR. FRITS MOOI: After a pertussis infection it has been shown to get super infections, in fact that is one of the main complications, pneumonia. FARYON: Young babies aren’t able to cough up secretions that collect in their lungs, leading to pneumonia and making it difficult to breathe. Early antibiotic treatment is most critical in this age group. Whooping cough was nearly wiped out by the late 1970’s because of mass immunization, but it’s somehow found its way back to California and other highly vaccinated communities around the world. Just why it’s made such a vengeful comeback has two of the world’s leading whooping cough experts in disagreement. Dr. James Cherry of UCLA: CHERRY: The main reason is increased awareness. FARYON: and Dr. Frits Mooi of the Netherlands Centre for Infectious Diseases Control. MOOI: We found really a new mutation in the bug. FARYON: Dr. Mooi and Dr. Cherry both began their research into Whooping Cough about 30 years ago. Cherry in the U.S. and Mooi in The Netherlands. The two scientists know each other's work. CHERRY: First of all, his molecular microbiological is, he's right at the top of scholars. There's no question about that. I think where some of the things he's published is the clinical data are not very good. MOOI: I don't communicate too much with him but what he wrote in the press is that I screw up epidemiology. That doesn't help me too much. FARYON: To understand why these two experts disagree, you need to know a little about the history of the pertussis vaccine. ANNOUNCER: Since most serious cases occur before school age, immunization in school may be too late. FARYON: The bacteria that causes whooping cough was first isolated in Belgium in 1906. At the time, the illness was one of the leading causes of infant death. ANNOUNCER: In 1921, whooping cough killed 316 Michigan children. Last year, the number of deaths was reduced to 63. FARYON: The discovery lead to the first attempts at a vaccine. But it wasn’t until the late 1940’s scientists developed a vaccine effective enough to prevent whooping cough. ANNOUNCER: Unlike the disease however, a vaccine does not endanger life. FARYON: By 1946, mass immunization programs began in the U.S. and the number of cases dropped dramatically. Prior to the vaccine the rate of disease was 157 cases per 100,000. By the 1970’s, with large scale immunizations, fewer than one in one hundred thousand people got whooping cough. But the vaccine was not without controversy. The early versions were associated with side effects such as prolonged crying spells and seizures in babies. By 1996, the FDA approved a new whooping cough vaccine. It was called an acellular version. That means the vaccine uses only purified components of the disease-causing organism. That vaccine was considered to be safer and associated with few mild side effects. Today, the U.S. uses only the acellular pertussis vaccine. But as the United States was changing vaccines something else was happening – health officials across the country were reporting increasing numbers of positive whooping cough cases. And in a government lab about 30 minutes outside of Amsterdam, a group of scientists had discovered something else – the bacterium that causes whooping cough started to look a little different. MOOI: This new mutation had the effect that the bacteria started to produce more pertussis toxin. FARYON: Just whether that mutation is to blame, at least in part, for the California epidemic and outbreaks elsewhere in the world is at the heart of the whooping cough debate. Dr. Mooi believes this to be the case, but not Dr. Cherry. CHERRY: Even though these changes have occurred there is no evidence that that’s lead to increased vaccine failure. FARYON: Here in San Diego County, more than 85 percent of children are immunized. In fact, less than three percent of kids entering kindergarten have not been immunized because of their family’s personal beliefs. But despite the high immunization rate, San Diego has the second largest number of positive whooping cough cases in California. Dr. Dean Sidelinger is San Diego’s deputy public health officer. DR. DEAN SIDELINGER: This is a disease that if someone has it it’s very easy to transfer from one person to another. So if you or I sitting here during this interview, one of us had pertussis chances are we could transmit that to the other person. Sidelinger says in the past, the number of whooping cough cases peaked in summer and slowed by fall, but this year, that didn’t happen. SIDELINGER: So as time goes on we’re seeing more cases. We know that public awareness plays into that as we talk about pertussis more people are asking their doctors and doctors are asking their patients we’re going to see more, but that trend continued. FARYON: By the end of November 2010, nearly 1000 infants, children and adults in San Diego County tested positive for whooping cough. More than half of them had been immunized. Our investigation shows that trend continues throughout California. KPBS and The Watchdog Institute collected data from 9 California counties that report some of the highest infection rates. Our research shows that where immunization history is known, between 44 and 83 percent of people diagnosed with whooping cough were vaccinated. We looked at California Department of Public Health records too. In cases where vaccination history was recorded, more than 80 percent of infected people had been immunized. DR. MARK HORTON: From the epidemiology experts and the experts in vaccine that this is absolutely expected. FARYON: Dr. Mark Horton is the director of the California Department of Public Health. HORTON: If you've got a percentage of the population vaccinated and a percentage of those vaccinated that are still susceptible because the vaccine isn't perfectly effective or effective in all individuals, when you work out the arithmetic you'll see that even with a very effective vaccine, and even if you have the majority of the population vaccinated, the pool of susceptibles will include a number of individuals that have never been vaccinated but will also include quite a few and in some cases greater than 50 percent of the individuals have been previously vaccinated. FARYON: In other words, if you do the math, you will always find a certain number of immunized people getting sick if a vaccine is not 100 percent effective. HORTON: So that’s no surprise to us nor is it a reflection on the efficacy of the vaccine. REPORTER KEVIN CROWE: It’s not a reflection on the efficacy of the vaccine? HORTON: Correct, correct. FARYON: But 20 years ago, the reverse was true. According to a report by the Centers for Disease Control, more than half of the children between 3 months and 4 years old who got whooping cough nationwide between 1990 and 1996 were not immunized. The rate of whooping cough has also been increasing for the past 20 years. From less than one in 100,000 to 18 per 100,000 here in California. And in some California counties such as San Luis Obispo, rates are nearly as high as before vaccines were developed. Two days after our interview with the Bryce family, Matthew got a fever. He was hospitalized at Rady’s Children’s Hospital in San Diego. Matthew was not immunized against whooping cough. He’s too young. Babies can’t be immunized until they’re two months old. But everyone else in the Bryce family was vaccinated – even his parents got booster shots. The practice of immunizing everyone around a newborn baby is called cocooning. CINDY BRYCE: When I called the doctor they asked me who has it and I couldn’t give them an answer because I don’t know where he got it from because everyone’s been vaccinated. FARYON: Myron and one of his sons were also tested for whooping cough – both were negative. M. BRYCE: The one thing I would want to know is the vaccine working? Is it as effective because before this I thought the vaccine was working and I thought that if I did everything that I was told to do that our sons would be protected. FARYON: Just how effective is the vaccine? That all depends on who you talk to. Drug information included with the two most commonly used whooping cough vaccines in the US say the vaccine is 85 percent effective. MOOI: This new strain has completely invaded the Netherlands and also other countries and pushed out all the other strains. It’s quite unique. FARYON: Dr. Mooi believes there’s no way to determine how effective the vaccines are because they have not been tested against the new strain of whooping cough. MOOI: We call it the p3 strain. FARYON: A strain he believes is more virulent and can make people sicker. This strain emerged while the new acellular vaccines were being developed. MOOI: I can tell you one of the reasons the vaccine companies is not too happy with me is because if what I say is true they selected the wrong strains the in the 1980’s. FARYON: Mooi’s lab was studying the new strain when The Netherlands experienced an unexpected whooping cough epidemic in 1996. MOOI: There were more strains in fact when you compare the two there was a very direct relationship between the emergence of these strains, we call them p3 strains and the increase in pertussis notifications. CHERRY: There’s absolutely no evidence that either of the two vaccines that are most common today used in the U.S. that there is increased vaccine failure with either of those vaccines. FARYON: So if you had to explain why we’re seeing this epidemic the highest number of cases in 60 years, what would you tell people? CHERRY: The main reason is increased awareness. People, particularly public health people are much more aware and that trickles down. FARYON: Cherry says the increase is also due in part because of something called waning immunity. Immunity to whooping cough does not last a lifetime, whether you are vaccinated or develop natural immunity from getting the disease. Almost all experts agree waning immunity is contributing to whooping cough outbreaks worldwide. Where they disagree: when does immunity fail? Dr. Mooi believes the new strain of pertussis causes immunity to fail sooner than in the past. And he’s published his findings in several peer reviewed journals including the CDC’s Infectious Diseases. MOOI: When the immunity is sub-optimal what will happen the bacteria will not be recognized very well by the immune system because of the mismatch and second of all even if immune response is started in the body the toxin will be able to delay it. You could say these two changes work together by decreasing the period of which the vaccine is protective further. FARYON: The Netherlands learned something else after its 1996 epidemic. At the time, it had very few samples of the bacteria that was causing people to get sick. So Mooi’s lab began asking doctors and their labs to send him positive pertussis swabs. His lab now has 3,000 samples. California that has collected just 29 samples from the more than 7,000 whooping cough cases in the state. During the KPBS/Watchdog four month investigation, we also learned data kept by the state and the CDC was often lagging behind county data and was inconsistent. While counties like San Diego knew the immunization status of the vast majority of people with whooping cough, the state’s data listed the information as unknown. Despite statewide protocols for reporting pertussis, a KPBS/Watchdog survey found some counties don’t follow them or are slow to report the information HORTON: There’s a perception that the more numbers the better, but let me be very clear we in no way need reports on every single case of pertussis for us to make important judgments and decisions about what’s happening. FARYON: The CDC in Atlanta declined our requests for an interview. In an email response they said it is “difficult to disentangle all the factors” contributing to increases in pertussis, but listed “increasing transmission, better recognition, and increased laboratory confirmation.” We also asked whether a new more virulent strain could be contributing to the outbreak. The CDC’s response: “Available data do not suggest that ptxP3 is more virulent, or that increasing reports are attributable only to the emergence of ptxP3. We continue to work on this and other potential explanations for the increase in pertussis that has occurred since the 1980s.” The CDC sent us this study by their own investigators. The study looked at children between 6 months and five years old. It found pertussis vaccines to be more than 90 percent effective. The study looked at data between 1998 and 2001. It did not collect pertussis strain information. SINGING: Do you happen to know what a T-dap is? It's a special vaccine but it's not just for kids. FARYON: Sanofi Pastuer, one of two companies that make the vaccine widely used in the U.S., sponsored this singing competition earlier this year. SINGING: Persussis is the reason why you should call your doctor today. FARYON: It was a public relations exercise to get the word out about whooping cough and immunization. But just where is the line between good PR and trying to influence public health policy? SINGING: Take a shot and give pertussis a whooping. FARYON: Especially when public health policy can increase vaccine sales. Since 2007, the California department of health has spent more than $200 million on pertussis vaccines for children on medical or who are under-insured. And it’s sure to rise. In September, the California state legislature passed a law requiring all students to receive another does, a sixth dose of the pertussis vaccine before entering middle school. It may be a case of what’s good for business is also good for public health. But how much influence does industry have over public health policy? Sanofi Pasteur also established and funds The Global Pertussis Initiative. A group made up of medical experts from around the world. The GPI was established 10 years ago to study why pertussis was making a comeback and find ways to control the disease. More than half its members are employees of the pharmaceutical company or receive research money or consulting fees. Public officials from across the country, including California and the CDC, site the Global Pertussis Initiative when making vaccine policy. Dr. James Cherry is a member of the initiative. He’s also received speaking fees and research funds from vaccine manufacturers. At the same time, he sat on government committees to help determine vaccine policy and efficacy. FARYON: A cynic might say that if you have a community of experts in pertussis as in the Global Pertussis Initiative, who primarily their work in terms of this endeavor is being funded by the drug company that makes the vaccine, there might be less incentive to say make a new vaccine and more incentive to say just use the old one more often. What do you say to them? CHERRY: I don’t think that’s true. I think that we’ve been talking about new vaccines. It think the difficulty with the new vaccine lies in the expense that it would cost to make a new vaccine and the difficulty in testing it and FDA requirements for it and I think if the climate was right for two of the major manufacturers they would do it. MOOI: And these are three different pertussis strains. FARYON: Dr. Mooi is a critic of the Pertussis Initiative. MOOI: My big disappointment is they have totally and I think willfully ignored pathogen adaptation. I think a few years ago we had the year that Darwin died 100 year ago, it was not so long ago, I think it's very strange that evolution and pathogen adaptation is completely ignored by such a group. I find that bad for science and bad for public health. FARYON: Sanofi Pastuer released this statement to KPBS and the Watchdog Institute. It says its grant to the GPI brings the world's authorities on pertussis together and that benefits society as a whole. The company also says “at the present time, there is no evidence to suggest current pertussis vaccines lack effectiveness.” Dr. Dean Sidelinger was one of the first health officials to learn immunized people were getting sick in his county. He said he was surprised, but in the end, he says the current vaccine is still the best thing he’s got to protect his community. SIDELINGER: It does significantly decrease the pertussis we see a significantly lower number of pertussis cases now then we saw before we started using the vaccine. So we don’t want people to feel complacent to say I don’t want that vaccine because I’ve seen many of the cases that have been reported were fully vaccinated. FARYON: Sidelinger says there would be many more cases if there was no vaccine at all. Dr. Mooi agrees. He believes public health officials should be encouraging cocooning, immunizing all those around newborn babies. But in the long run, he says we need better vaccines. Baby Matthew spent four days in the hospital and was eventually discharged. Today, he’s getting his two-month routine check-up. DOCTOR: I think it was just back luck he’s had two illnesses in a row and now the cold he's building up his immunity. FARYON: Despite a stuffy nose, Matthew is doing well today. DCOTOR: As you might know the vaccine is not as effective as we want it to be. And that's one reason why there've been a lot of cases. But with Matthew in particular, his own immunity has kicked in from having the illness, that is, in effect a sort of a booster that will protect him going forward. And how long that immunity lasts is still a question. MARLON: The one thing I would want to say to parents is just watch your kids, just be concerned. Because at first we thought we were being over protective. But I’m glad we were just a little bit over-concerned. FARYON: Since KPBS and the Watchdog Institute began its investigation, state health officials, the CDC and scientists from UCLA, including Dr. James Cherry, began a new study to determine whether the new strain of pertussis is contributing to the current whooping cough outbreak. For more on this story, and to see more of the data collected in our investigation, go to kpbs.org/whoopingcough and watchdoginstitute.org. For KPBS, the Watchdog Institute and Radio Netherlands Worldwide, I’m Joanne Faryon. Thanks for watching.