MMR vaccine (still) doesn't cause autism, new study finds

Nope.

We’re still spending vast amounts of time and money trying to counter the ill effects of a discredited, retracted paper from 1998 that claimed to find a link between the MMR (measles, mumps, and rubella) vaccine and autism. Even after the The Lancet retracted the study, and even after the British Medical Council revoked the medical license of its lead author, Andrew Wakefield, many people continue to withhold vaccines from their children because of a fear that somehow, despite all the evidence to the contrary, vaccines might cause autism. Vaccines, I hasten to add, have saved millions of lives and are probably the greatest medical advance of the past two centuries.

Now another study has appeared to add more weight to the evidence about the safely of the MMR vaccine. The new study by Anjali Jain and colleagues, just published in the Journal of the American Medical Association, looked at a huge number of children–95,727–for evidence of any link between autism and the MMR vaccine.

The results were not surprising, to those who have been following the science. To quote the conclusions directly: 

“Receipt of the MMR vaccine was not associated with increased risk of ASD [autism spectrum disorder], regardless of whether older siblings had ASD. These findings indicate no harmful association between MMR vaccine receipt and ASD even among children already at higher risk for ASD.”

That should settle it, right? But then, dozens of previous studies should have already settled this question. Unfortunately, due to the ongoing activism of anti-vaccine groups such as Age of Autism, (who already attacked this new study) and to conspiracy theorists such as Robert F. Kennedy Jr. (whom I wrote about last summer, and who was campaigning against vaccines in Vermont just last week), misguided claims that vaccines cause autism or neurological problems persist.

Here are the numbers from the new study. The authors compared vaccinated children to unvaccinated children, using a huge database of medical claims that included at least 5 years of followup. (This was an "observational" study, by necessity–it would be unethical to withhold vaccines from children on purpose.) The relative risk for autism in children who had 2 doses of the MMR vaccine (the recommended amount) compared to unvaccinated children was 0.74. In other words, a child was somewhat less likely to be diagnosed with autism if he or she were vaccinated. 

Even more surprising was the relative risk among children who had an older sibling with autism: in this smaller group, children with 2 doses of MMR were just 44% as likely to be diagnosed with autism as unvaccinated children. This statistically significant finding indicates, unexpectedly, that vaccines might actually protect children from autism.

The authors were quick to note that there are other good reasons for this apparent protective effect of vaccines: in particular, if parents of autistic children withheld vaccines from their younger children, this could explain the effect. Why? Because we know that autism has a genetic component, and that if one child has autism, his younger sibling is more likely (because they share many genes) to have autism as well. Jain and colleagues explained that if these parents withheld vaccines–because of fears spread by the anti-vaccine movement–then their children could contribute to the apparently lower rate of autism in children who were vaccinated. The authors couldn’t rule out a protective effect of vaccines, but scientifically it seems unlikely, and they wisely offered an alternative explanation.

So: once again we have a large, carefully conducted study showing that the MMR vaccine does not cause autism, and even finding evidence that vaccinated children have lower rates of autism. Let's hope this study helps to end the anti-vax movement, so that we can soon stop spending time and money trying to refute their long-discredited hypotheses and instead focus on trying to understand the true cause.

Brief note: a new vaccine mythbuster site appears

Vaccines are probably the single greatest advance in public health ever invented. Despite their enormous benefits, and the overwhelming evidence in their favor (we've wiped out smallpox and nearly wiped out polio), anti-vaccine activists continue to spread rumors and wildly inaccurate, but scary tales about the potential harms of vaccines.

Today a new website was published, a collection of 100 other sites that provide good information on the benefits of vaccines, and that bust many of the most damaging anti-vaccine myths.  This site is on the list, but you'll find many other excellent sources of good science about vaccines.  We need every bit of help we can get to counter the mis-information about vaccines promoted by groups such as Generation Rescue and Age of Autism.

IOM to Public: Childhood Vaccine Schedule is Safe

Hey parents: if you've been taken in by anti-vaccine discussions on the internet, you might want to look at the newest report from the Institute of Medicine.  After a lengthy and thorough review of the evidence, the IOM issued a report last week that found that the current childhood immunization schedule in the United States is safe.

The IOM committee specifically looked for evidence that vaccination is linked to "autoimmune diseases, asthma, hypersensitivity, seizures, child developmental disorders, learning or developmental disorders, or attention deficit or disruptive disorders", including autism.  Their finding: no evidence suggests a link to any of these conditions.

The motivation for the report is the growing incidence of parents who worry that there are "too many, too soon" - a catchphrase that was the basis of an anti-vaccine campaign led by Generation Rescue and its spokesmodel, Jenny McCarthy.  This concern, which sounds reasonable on its face, never had any evidence to support it.

Anti-vaccine activists have pointed out, correctly, that the number of vaccines has increased significantly over the past several decades.  The current schedule has as many as 24 immunizations in a child's first two years, and up to five injections in a single visit.  The reason for this is simple: the scientific community has developed vaccines against a growing number of childhood illnesses.  As a result, many diseases that used to infect millions of children each year, killing or permanently injuring thousands of infants and toddlers, have almost disappeared from modern societies.  This is a good thing.

Many parents have been convinced to "slow down" vaccines after hearing advice from self-proclaimed vaccination authorities, such as "Dr. Bob" Sears.  Sears has published his own alternative vaccine schedule (which he apparently just made up - he certainly didn't do a scientific study) and whose has gotten rich selling his book and offering other advice.  Journalist Seth Mnookin calls Sears "a first-rate huckster."

Noted vaccine expert Paul Offit, in a peer-reviewed article in the journal Pediatrics four years ago, explained how Sears ignores all the science on vaccine safety, sometimes simply replacing objective evidence with his own "facts." Offit also called out Sears for his advising parents not to vaccinate their kids, but then not to tell their neighbors:

“I also warn [parents] not to share their fears with their neighbors, because if too many people avoid the MMR, we'll likely see the diseases increase significantly.” [wrote "Dr. Bob" Sears]  

In this astonishingly selfish comment, Sears admits that herd immunity works, but then says don't tell your neighbors, because then their kids might get sick and infect your unvaccinated kids.

Offit's article is a thorough, point-by-point rebuttal of Sears' numerous claims, many of them either misleading or downright false.  I highly recommend it.  Or  read the IOM's report online, for free.  Don't waste your money on Dr. Bob's book.

Let's hope all parents will follow the recommended vaccine schedule and ignore the voices of fear and unreason who are trying to scare them.  If you're still in doubt, read the heartbreaking story, from just a few days ago, of 7-year-old Alijah Williams in New Zealand.  Alijah's well-educated parents thought they were doing the right thing by withholding vaccines, after reading some scary material on the internet.  Alijah was infected with tetanus last year and fought it for months, nearly dying in the process.  His recovery will take 12 months, during which he will have to re-learn how to eat and walk on his own.  His parents have now become activists trying to spread the word among their community that infections are the real threat - not vaccines.

Congress holds an anti-vaccine hearing

I was in my car yesterday listening to C-SPAN (yes, I do that sometimes), when to my stunned surprise I heard Congressman Dan Burton launch into a diatribe on how mercury in vaccines causes autism.  No, this was not a replay of a recording from a decade ago.  The hearing was held just a few days ago by the Committee on Oversight and Government Reform.

Congressman Burton used this hearing to rehash a series of some of the most thoroughly discredited anti-vaccine positions of the past decade.  Burton is a firm believer in the myth that vaccines cause autism, and he arrogantly holds the position that he knows the truth better than the thousands of scientists who have spent much of the past decade doing real science that proves him wrong.  

In a classic political move, the committee called on scientists Alan Guttmacher from the NIH and Colleen Boyle from the CDC to testify, but in fact the committee just wanted to bully the scientists.  Committee members lectured the scientists, throwing out bad science claims, often disguised as questions, thick and fast.  Alas, Guttmacher and Boyle weren't prepared for this kind of rapid-fire assault by pseudoscience.

Burton himself was the worst offender, offering anecdotes and bad science with an air of authority.  He stated bluntly: 

“I’m convinced that the mercury in vaccinations is a contributing factor to neurological diseases such as autism."

No, it isn't.  Dozens of studies, involving hundreds of thousands of children, have found the same thing: there is no link whatsoever between thimerosal and autism, or between vaccines and autism.  And Burton went off the deep end with this: 

"It wasn’t so bad when a child gets one or two or three vaccines… Mercury accumulates in the brain until it has to be chelated.” 

Bang bang, two false claims in 10 seconds.  First he claims that mercury from vaccines "accumulates in the brain", a statement with no scientific support at all. Then he claims that chelation therapy is the solution - a radical, potentially very harmful treatment that no sensible parent would ever force on their child.  Unfortunately, some quack doctors have experimented with chelation therapy on autistic children, despite that fact that it can cause deadly liver and kidney damage, and one of them caused the death of a 5-year-old boy in 2005.

Burton also claimed that single-shot vials would "eliminate the possibilty of neurological damage from vaccines" - a claim that was invented out of thin air by the discredited anti-vax doctor Andrew Wakefield, whose fraudulent 1998 study was the spark that started the current wave of anti-vax hysteria.

Congressman Bill Posey from Florida was just as bad as Burton, demanding a study of vaccinated versus unvaccinated children, a standard talking point of the anti-vax movement.  (Congressman Posey: do you even realize that your question is almost identical to what Jenny McCarthy asked five years ago, on the Larry King Live show?)  Here's his question to the CDC's Boyle:

"I wonder if the CDC has conducted or facilitated a study comparing vaccinated children with unvaccinated children yet - have you done that?"

Dr. Boyle wasn't prepared for this.  She tried to point out that many studies have been done looking at the relation between vaccines and autism, but she didn't get very far before interrupted, thus: 

Rep. Posey: “So clearly, definitely, unequivocally, you have studied vaccinated versus unvaccinated?” 

Dr. Boyle: “We have not studied vaccinated versus unvaccinated." 

Posey: “Never mind. Stop there. That was the meaning of my question. You wasted two minutes of my time."

Dr. Boyle simply wasn't prepared for a Congressman who was parroting anti-vax activists.  It's too late now, but her response should have been this:

Congressman Posey, only an extremely unethical scientist would consider conducting such a study.  To compare vaccinated versus unvaccinated children in the manner you suggest, one would have to withhold vaccines from young children.  We know from decades of evidence, involving tens of millions of children, that vaccines save lives.  Few if any medical interventions are more effective than vaccines. 

But Congressman, the scientific community has done observational studies of vaccinated versus unvaccinated children, comparing autism rates in children whose parents chose not to vaccinate.  Those studies show that autism rates were slightly higher in unvaccinated children.  That's right, vaccinated children had autism at a lower rate. 

So no, Congressman Posey, the CDC hasn't done a study of vaccinated versus unvaccinated children.  Only a corrupt dictatorship could impose a study like that on its people.  Is that what you want?

To make matters worse, the House committee invited Mark Blaxill to testify.  Blaxill is a well-known anti-vaccine activist whose organization, SafeMinds, seems to revolve around the bogus claim that mercury in vaccines causes autism.  His organization urges parents not to vaccinate their children, and giving him such a prominent platform only serves to spread misinformation among parents of young children.  

Blaxill's central claim is that that we're in the midst of an autism epidemic: 

"For a long time, reported U.S. autism rates were low, estimated at about 1 in 10,000. Then around 1990 something new and terrible happened to a generation of children. Autism rates didn’t just rise, they multiplied," claimed Blaxill in his written testimony.

His entire argument builds on this.  Yet multiple studies, looking carefully and objectively at the data, indicate that all or nearly all of the rise in autism cases is due to increasing diagnoses, which in turn is due to multiple factors: a dramatically broading of the definition of autism in the early 1990s, a greater awareness of the condition, and a greater willingness of doctors and parents to accept the diagnosis.  For an objective summary of the evidence, see the articles by neurologist Steven Novella here and here, which summarize a dozen epidemiological studies.  The weight of the evidence shows that the actual incidence of autism is either stable or possibly rising very slowly.  There is no "autism epidemic."

It's also worth pointing out that Blaxill is a conspiracy theorist who claims that the "CDC has actively covered up the evidence surrounding autism’s environmental causes."  

Congress has every right to conduct oversight into medical research at the NIH and the CDC.  But when Dan Burton, Bob Posey, and others decide in advance what the science says, and abuse their power to demand "answers" that validate their badly mistaken beliefs, people can be harmed. Over the past decade, the anti-vaccine movement has successfully convinced millions of parents to leave their kids unvaccinated, and the result has been serious outbreaks of whooping cough, haemophilus, measles, chicken pox, and mumps around the U.S. and Europe.  

Some anti-vax parents claim that these childhood illnesses aren't so bad.  I wish they would talk to the parents of young children who have died in recent whooping cough outbreaks.  These illnesses can be deadly.

Message to Congress: science isn't easy, and autism is complicated.  Don't criticize science when it doesn't give you the answer you thought you knew.  That's not how science works.  Thousands of scientists are now trying to identify the causes of autism, and they've made progress, especially on the genetic front.  The answer might not be simple, but we will find it.  

A surprising triumph in the fight against polio

Source: polioeradication.org

The last case of polio in India occurred exactly one year ago, on January 13, 2011.  In the decades-long battle against this devastating disease, this is one of the best pieces of news in a long time.  Just two years ago, health officials counted 741 polio infections in India, and it seemed that the battle was far from over.  It may yet be, but in 2010 the cases dropped dramatically, to just 42, and last year there was only one, on January 13.


As recently as the 1950s, polio was a dreaded, incurable disease that killed or paralyzed millions of children each year.  The U.S. alone had 58,000 cases in 1952. Then came the invention of a vaccine by Jonas Salk, one of the great medical breakthroughs of the 20th century.  By the 1960s, widespread vaccination campaigns had virtually eliminated polio from Europe and the U.S.  Polio lingered in the U.S., mainly in the Amish population who refused to accept vaccinations, but it finally disappeared in 1979.

The worldwide campaign to eliminate polio started in 1988, when 350,000 infections were recorded.  Polio is extremely difficult to control, because a large majority of infected people show no symptoms, but they can still spread the virus.  Vaccination campaigns need to treat everyone who comes in contact with an infected individual in order to break the cycle of transmission.  This is especially hard to do in remote areas of poor countries, especially when the populace is suspicious and uncooperative.

The greatest challenge in India came in the desperately poor, crowded regions of the north, where health care, hygiene, and education are all very poor.  The vaccination efforts were made even more difficult by conspiracy theories among the Muslim population.  As Simon Denyer wrote in the Washington Post this week:

"Rumors spread among the region's numerous Muslims that the polio vaccination campaign was an American conspiracy to wipe them out, by making their sons impotent and their daughters infertile.... Vaccinators were stoned as they approached Muslim neighborhoods. 'The general mind-set was that the immunization campaign was aimed at ending our lineage,' said Anwar Ahmad, the head of a madrassa in a Muslim neighborhood in the city of Meerut."

The campaign turned around after UNICEF and Rotary international launched a major education effort that first convinced Muslim leaders, and then everyone else, that the vaccine would benefit their communities.  With this success in India, polio is now endemic in only three countries in the world: Afghanistan, Pakistan, and Nigeria.  The same rumors and conspiracy theories that plagued India have spread within Muslim populations in these countries as well, but India shows that the misinformation - and polio - can be defeated.

Unfortunately, even here in the U.S. we have our own conspiracy theorists: the anti-vaccination zealots over at Age of Autism, where Dan Olmsted and Mark Blaxill recently posted a series of articles claiming that polio is "a harmless intestinal bug" that only causes disease when triggered by pesticides or by arsenic.  Never mind that there is no evidence to back this truly wacky assertion; these two anti-vaxxers seem happy to invent facts to support their single-minded campaign against all vaccines, even when the vaccines are demonstrably saving tens of thousands of lives.

Polio is still with us, and it could return.  Besides the 3 countries with endemic polio, 9 other countries continue to suffer polio cases that were imported from endemic countries.  Without widespread vaccination in those countries, polio could re-establish itself in any of them.

If polio stays out of India, we can thank the thousands of health care workers who traveled to remote villages, in extremely difficult conditions, to dispense lifesaving vaccines.  Their heroic efforts have paid off for everyone.  We should also thank the combined efforts of the WHO, UNICEF, Rotary International, the Gates Foundation, and the CDC, all of whom are backing the worldwide effort to eradicate polio.  Let's root for humanity to win this one.

Chronic fatigue syndrome hypothesis collapses further

Two years ago, a team of scientists announced with great fanfare that they'd found the cause of chronic fatigue syndrome: a mouse retrovirus called XMRV. There were many media reports and much excitement, and at least a dozen studies were launched to look for this virus in more patients. Unfortunately for patients, the findings turned out to be seriously flawed.

New results published this week seem to be the final nail in the coffin for the XMRV hypothesis. The editors at Science have taken the unusual step of publicly asking the authors of the 2009 study to retract their findings. As reported in the Wall St. Journal, Science sent a letter to the authors stating:

"At this juncture, Science feels that it would be in the best interest of the scientific community'' for the co-authors to retract the paper."

In addition, the editors published an "expression of concern" this week, which is their way of warning everyone that the results are wrong. Judy Mikovits, the leader of the study, steadfastly insists that she is right and all the others are wrong.

Despite Mikovits' claims, the evidence is very clear that she is wrong. Study after study has found no trace of the virus in CFS patients. Where Mikovits' original study found 67% of the patients had XMRV, followup studies found 0%. A set of three papers in the journal Retrovirology, published in December, showed conclusively that the finding was due to laboratory contamination. The XMRV virus turned up as a contaminant in cancer cell lines that are widely used in laboratory research. As I wrote in January:

"It turns out that a common tumor cell line called 22Rv1 is infected with MLV-X. It also turns out that all the XMRV sequences from human patients are far more similar to the exact same strain of MLV-X that is in the mouse cell line. The tumor cell line was in the lab doing the experiments: ergo, it's contamination. Elementary, my dear Watson."

Two new papers in Science this week found the same thing. One of them, titled "No Evidence of Murine-Like Gammaretroviruses in CFS Patients Previously Identified as XMRV-Infected" looked at patients who had tested positive for the XMRV virus, and found that they didn't have it all. The second study provides new detail on how the XMRV virus got into the cancer cell lines.

So why does Mikovits cling so fiercely to her claims? (She posted a long letter defending herself at the Whittemore Peterson Institute, where she works.) What she doesn't say is that she has gone far beyond her original findings: she and her institute are actively promoting the use of anti-retroviral therapies for CFS patients. As Nature News reported in March,

"The WPI owns a company that charges patients up to $549 to be tested for XMRV, and Mikovits believes that patients who test positive should consult their doctors about getting antiretroviral drugs normally prescribed to those with HIV."

This is a blatant conflict of interest, and it perhaps explains some of Mikovits' stubbornness.

It gets worse. As Trine Tsouderos reported last summer in the Chicago Tribune, Mikovits claimed at the Autism One conference that XMRV also causes autism. She has no evidence to support this startling claim. Mikovits stated to the Tribune that "unless we do something now this (XMRV) could be the worst epidemic in U.S. history."

Mikovits also believes there is a conspiracy against her. In March, she told Nature "I had no idea there was that much bias against this disease." Nonsense. The collapse of the evidence about XMRV and chronic fatigue syndrome is just science doing what it is supposed to do: when a study cannot be replicated, then the hypothesis is abandoned and we move on.

This is a classic tale of a scientist gone bad. Unfortunately for CFS patients, Mikovits is distracting attention from efforts to find the real cause. By speaking at the Autism One conference, she has joined the ranks of pseudoscientists and anti-vaccinationists. It's pretty clear now that she will never retract her findings, despite the pressure from the editors at Science. I can only hope that CFS patients, who are understandably desperate for a treatment, won't be fooled into taking ineffective and possibly harmful therapies based on the failed XMRV hypothesis.

Measles invades U.S.: anti-vaccine movement scores again

How can we keep unvaccinated people from bringing infectious diseases into the U.S.? These diseases are a real threat to public health, and while we're spending billions on national security, almost all that money goes towards "security theater," such as full-body scanning equipment at airports, which does almost nothing to protect the public. We'd be much better off spending those scarce funds on detecting infections at the border.

In the most recent invasion, the measles virus has snuck in thanks to a single unvaccinated student from Utah, who picked up the disease in Poland. The junior high student traveled to Poland with his family to pick up his sister, who was there as a Mormon missionary. As reported by the Associated Press, up to 1000 people have already been exposed, and the circle could easily spread beyond that.

Measles is a dangerous and incredibly infectious virus, transmitting easily between people. According to the CDC:

"About one out of 10 children with measles also gets an ear infection, and up to one out of 20 gets pneumonia. For every 1,000 children who get measles, one or two will die."

This is not a disease to take lightly. Fortunately, the vaccine is highly effective, which means the real challenge is getting people to take it.

Utah requires measles vaccinations for public schools, but (as in many other states) parents can refuse vaccines for personal or religious reasons. California now has about 2% of parents refusing vaccines for their children for personal beliefs. This gaping hole in our public health system needs to be closed: if parents refuse to vaccinate their children, they are putting the rest of us at risk, and these children need to be kept out of public schools.

Most of the parents refusing vaccines for the children are doing so out of fear that vaccines cause harm. Despite countless studies showing that vaccines are safe (and in particular, that vaccines do not cause autism), these rumors persist, amplified greatly by the anti-vaccine movement, which seems impervious to evidence or reason.

Meanwhile, anti-vaccine groups such as Age of Autism are fighting to keep or even expand these exemptions. Other sites such as ThinkTwice.com http://www.thinktwice.com/laws.htm and Internet quacks Joseph Mercola and Sherri Tenpenny advise parents to refuse vaccination and use whatever loopholes they can to enroll their kids in school. Parents who follow this advice rely on the immunization of others to protect their own children, but they appear unconcerned about the risk they forcing on the rest of us. They also neglect to consider that vaccines are never 100% effective, so even those of us who vaccinate our kids are still bearing a greater risk by allowing the unvaccinated to attend school.

Europe has its own problems with vaccine coverage, and measles is spreading rapidly this year, having hit 24 countries so far. France had 3749 cases and one death in the first two months of this year. Many of the victims are children too young to be vaccinated, but the disease is often spread by people who simply refuse to get the vaccine.

The latest measles outbreak in Utah could have been avoided if the student involved had simply been vaccinated. Realistically, though, we will always have citizens traveling abroad and bringing infectious diseases back. If the U.S. really wants to use its security dollars wisely, we should implement greater screening at the border to keep these disesases out. We could start by telling people to get vaccinated before they leave the country. If they refuse, we could require them to be tested for infections when they return. We could implement this using funds we'd save when we stop telling everyone to take off their shoes at the airport.

Supreme Court saves the vaccine system

Unbeknownst to most people, the Supreme Court heard a case last week that, had they ruled differently, might have destroyed the vaccine system in the United States. On February 22, the court ruled 6-2 to keep the special Vaccine Court system intact. In particular, they ruled against Russell and Robalee Bruesewitz, who were suing for damages on behalf of their daughter Hannah. But even though the system is saved for now, the two judges who voted in the minority demonstrated a frightening disregard for possible consequences, and encouraged those who would like to take us all back to an era when millions of children died each year from diseases like measles, polio, and whooping cough.

Hannah Bruesewitz's case is heartbreaking: she suffered a seizure in April 1992, within a day of receiving the vaccine for diphtheria, pertussis, and tetanus (DPT), and she had many more seizures in the following months. She was eventually diagnosed with with “residual seizure disorder” and “developmental delay" which she still has today. Her parents blamed the vaccine, and in 1995 they sued in Vaccine Court. They lost, although the Special Master of that court awarded them $126,800 for lawyer's fees and other costs. The Bruesewitzes rejected the award and sued in a state court in Pennsylvania.

The case last week wasn't about whether Hannah's disability was caused by the DTP vaccine. It was only about whether her parents could sue in state court after losing their case in vaccine court. The Supreme Court said no. Had they allowed the case, state courts across the country would have been flooded with thousands of vaccine lawsuits, and it is entirely likely that vaccine makers would simply stop selling vaccines in the United States. The ensuing loss of vaccines would be a public health disaster of enormous magnitude, leading to tens of thousands of deaths from diseases that we now have largely defeated in this county.

This sounds awfully dire. Why do I claim it could happen? Because it almost did, some 25 years ago.

Back in the 1980s, largely due to one incredibly irresponsible, inaccurate television documentary called DPT: Vaccine Roulette "started a firestorm" of panic, as Paul Offit explains in his latest book (1). It also caused an avalanche of lawsuits, and juries were soon making multi-million dollar awards. As Dr. Offit documents, jury awards in vaccine cases increased from $25 million in 1981 to $3.2 billion in 1985. Two of the three companies making the DPT vaccine stopped distributing it, leaving only one company, Lederle (now owned by Wyeth) supplying it.

It wasn't just DPT. Companies making measles and polio vaccines also dropped out of the U.S. market, leaving just one company for each. We were very close to a situation where we simply wouldn't have childhood vaccines in this country.

Then, remarkably, the federal government passed the National Childhood Vaccine Injury Act of 1986. This set up a special fund to compensate anyone damaged by vaccines, covered by a tax on all vaccines. It also created a special Vaccine Court to hear cases, and required that vaccine cases go through this court. The standard of evidence for the court was lower than regular courts: for some conditions, the parents merely have to show that their child suffered the condition soon after getting a vaccine, regardless of whether the vaccine was the cause.

The law also took juries and state courts out of the equation. Vaccine makers were protected, and the childhood vaccination system was saved. The Vaccine Court functions remarkably well, using Special Masters who become far more educated about vaccines and possible side effects than any regular judges can be. There is a very small but real risk of harm from vaccines, and the Vaccine Court has made thousands of awards to compensate victims. Meanwhile, millions of severe illnesses and countless thousands of deaths have been prevented by vaccines.

So I was very dismayed that two justices, Sandra Sotomayor and Ruth Bader Ginsburg, voted against the majority. I usually agree with these two, but their reasoning in this case was wildly off. Sotomayor's dissent shows her to be misinformed, confused, or just plain naive:

"Trial courts, moreover, have considerable experience in efficiently handling and disposing of meritless products liability claims, and decades of tort litigation (including for design defect) in the prescription-drug context have not led to shortages in prescription drugs. Despite the doomsday predictions of respondent and the various amici cited by the concurrence ... the possibility of a torrent of meritless lawsuits bankrupting manufacturers and causing vaccine shortages seems remote at best."

Apparently Sotomayor is unaware of the actual "torrent of meritless lawsuits" from the 1980s that forced Congress to create the Vaccine Court in the first place, although I cannot understand how she could fail to know this history. I am also disappointed by her naive faith in trial courts to quickly dispose of "meritless product liability claims." Perhaps in an ideal world, yes. But a smart lawyer, a sympathetic victim, and a complex medical case can easily confuse both judge and jury, leading to enormous jury awards regardless of what the scientific evidence shows.

Apparently Sotomayor can't bear to limit the ability of plaintiffs to sue wherever they choose. The Vaccine Court, although imperfect, is a much better model for handling complex medical claims than the roulette of a jury trial. We should all breathe a sigh of relief that the Supreme Court kept this system intact.

Of course, the anti-vaccination movement has been quick to attack the decision. Age of Autism, one of the biggest anti-vax sites, posted an article titled "Supreme Court Ruling Abandons Vaccine-Injured Children, Threatens Vaccine Safety" in which they call the decision "a crushing blow to the rights of every U.S. citizen." A coalition of anti-vax organizations including Generation Rescue issued a press release calling the decision "misguided" and making a number of incorrect claims about vaccine safety. But scientists and doctors, notably the American Academy of Pediatrics, applauded the decision.

Reference

1. Paul A. Offit, M.D. Deadly Choices: How the Anti-Vaccine Movement Threatens Us All. Basic Books (2011). See especially pages 2-12.

At the movies: popcorn and anti-vaccine fearmongering

The anti-vaccinationists have launched a new campaign this holiday season to spread cheer – oops, I mean fear – to moviegoers everywhere. Yes, the folks at SafeMinds and Age of Autism have produced an advertisement that they are trying to place in AMC theaters across the country. In fact, they almost succeeded, but quick action by skeptical science bloggers at SkepChick, Respectful Insolence, and their readerships convinced AMC to cancel the ad – for now.

The ad that SafeMinds is trying to run is intended to scare people away from getting their flu vaccine, just as flu season is beginning. The vaccine this year will protect you against both the new “swine” flu, called H1N1, and the previous flu strain, H3N2. Early data from the CDC makes it clear that both strains are still around, with H3N2 showing up somewhat more frequently so far this fall. The vaccine not only protects you, but also your family, your colleagues, and the many other people you might come into contact with each day while at work, shopping, or elsewhere.

Why try to scare people? Well, the people behind SafeMinds and Age of Autism believe that the preservative thimerosal, which is used in some but not all flu vaccines, causes autism. This theory has been thoroughly investigated over the past 10 years, and just as thoroughly discredited. In fact, it never had any positive evidence to support it in the first place, but it has been promoted aggressively by a journalist, David Kirby, who made his fortune off a book based on the thimerosal-autism hypothesis. (I’m not providing a link – Kirby has already made far too much money off this bogus claim, and I don’t want to give him the web traffic.)

Thimerosal was introduced into vaccines in the 1930s, and it is a very effective means to prevent the growth of bacteria without affecting the potency of the vaccine itself. In over 60 years and hundreds of millions of doses, it has proven to be quite benign. Nonetheless, it contains a form of mercury called ethylmercury, which anti-vaccinationists claim causes autism and other neurological disorders.

The claim that thimerosal causes autism was the central question of a large, multi-year Autism Omnibus trial, which ruled definitively last year that thimerosal does not cause autism. I wrote about that ruling at some length back in March, and I won’t repeat it here, except to quote again from the Special Master’s decision:

“The numerous medical studies concerning the issue of whether thimerosal causes autism, performed by medical scientists worldwide, have come down strongly against the petitioners’ contentions. Considering all of the evidence, I find that the petitioners have failed to demonstrate that thimerosal-containing vaccines can contribute to the causation of autism.”

The anti-vax crowd will not give up, unfortunately. Rather than spending their time and effort trying to find the true causes of autism, they continue to repeat claims that have already been shown false. For example, the SafeMinds website lists 5 “key points” that are just flat-out wrong. Here are the first two:

1. “The autism epidemic that began in the late 1980’s is likely due primarily to toxins adversely affecting fetus and infants during development.” Wrong, in at least two ways. First, there is no autism “epidemic.” The best evidence today indicates that the rising rates of autism are due to a combination of factors, primarily (a) rising rates of diagnosis due to increased awareness among physicians and patients and (b) a dramatically broader medical definition of autism that was introduced in the early 1990s.
2. “Mercury is likely a major contributor to this toxin-induced autism, whether the source of the mercury is from vaccines or environmental mercury exposure.” Wrong again. This is the claim that was so thoroughly refuted in the lengthy Autism Omnibus trial, with hundreds of pages of testimony from dozens of experts, and epidemiological data from literally hundreds of thousands of people.

But data doesn’t seem to have any effect on the anti-vax zealots at Age of Autism and SafeMinds.

Because AMC refused to run their ad, Age of Autism is telling its readers to stay away from AMC theaters this holiday season. I hope they do! Why? Because these unvaccinated individuals are a genuine threat to public health. Movie theaters, and the malls in which they are located, are an ideal place for infectious diseases to spread. Without vaccines, countless thousands of people would fall ill every holiday season after mingling with other shoppers, and some would likely die. My message to the unvaccinated crowd at SafeMinds is: stay away from the rest of us.

And I encourage everyone else to get your flu shot, get your kids vaccinated, and then go see a movie at an AMC theater. Meanwhile, you can also tell them at this link that you appreciate their taking a stand against misinformation and for the benefit of public health.

Whooping cough in California: deaths caused by the anti-vaccination movement

California is suffering the worst epidemic of pertussis, or whooping cough, in 60 years, with over 5,200 cases already, the most since 1950. Nine babies have died, all of them too young to receive the vaccine. Michigan is also reporting a serious outbreak, with over 600 cases so far this year. The deaths of the infants in California are tragic, and what’s more tragic is that some of them almost certainly could have been prevented if more people had been vaccinated.

The pertussis vaccine, called DTaP (diphtheria, tetanus, and pertussis) has been responsible for a dramatic drop in whooping cough in recent decades. It isn't 100% effective, but its effectiveness relies in part on “herd immunity”: if enough people are immune to the bacteria, then even if someone gets sick, the disease cannot easily spread through the community. This is especially true for very young infants, who are too young to be vaccinated and whose immune systems are not yet strong enough to defeat the bacteria on their own.

Unfortunately, it’s not a coincidence that California is the center of the new pertussis epidemic. Vaccination rates among adults in California have been dropping in recent years, largely due to the influence of anti-vaccination zealots such as Jenny McCarthy and groups such as Age of Autism. Anti-vaccination sentiments seem to strike a chord with relatively well-educated segments of the population – the same people who favor organic food and want to use “natural” products as much as possible. Anti-vaxers appeal to this group by arguing that vaccines are unnatural, and that the body’s own immune system can be “boosted” by various natural treatments. Appealing though this may sound, it has no basis in science. California makes it easy for parents to claim exemptions from the required vaccinations for their children, and exemptions have more than doubled since 1997, according to the L.A. Times.

Among the anti-vaccinationists who deserve blame for the current pertussis outbreak is “Dr. Bob” Sears, a kindler, gentler anti-vaxer who claims (like many of them) to be in favor of vaccines, but only under his own, unscientific terms. He stated flatly in the Huffington Post (a hotbed of medical misinformation) recently that pregnant women should not get the DTaP vaccine. But as Dr. Paul Offit tells us in a tragic story, refusing the vaccine can lead directly to the death of an infant. Dr. Bob is just wrong. I should add that Sears has written two books on vaccines and autism, promoting his misguided “alternative” vaccine schedule (see this article in Pediatrics about that) and his rather naive theories about the rise in autism diagnoses.

Everyone should have their children vaccinated. On top of that, in order to maintain herd immunity, most of us should get the pertussis booster shot if we haven’t had one in the last ten years. That’s what vaccine expert Paul Offit recommends, and I’m planning to follow his advice myself. It won’t take long, and it might save a life.