Denialism (7 page)

It was, in the highly emotional words of one vaccine activist who rejects the federal government’s approach, a conspiracy among scientists to protect pharmaceutical companies at the expense of America’s children. Because this is the age of denialism, evidence that
any
pharmaceutical company has engaged in venal behavior means that they
all
have. “When mothers and fathers take their healthy sons and daughters to pediatricians to get vaccinated and then witness them suffering vaccine reactions and regressing into chronic poor health within hours, days and weeks of getting sometimes five to ten vaccines on one day, they are not going to accept an illogical, unscientific explanation like ‘it’s all a coincidence,’ ” Barbara Loe Fisher has written. Fisher is the leader of the National Vaccine Information Center, the most influential of the many groups that oppose universal vaccination. (This sentiment, that children receive too many vaccinations when they are young, also draws frequently on anecdotal experience and the sort of conspiracy theories that are hallmarks of denialism: “No wonder our children are damaged and dealing w/ADHD, autism, diabetes, asthma, allergies, etc.,” Fisher wrote. “Forty-eight doses of fourteen vaccines by age 6 is excessive and is only for the benefit of the drug companies who promote fear to fund their bottom line.”)

The vaccine panel found itself at ground zero in this war against authority and scientific rigor. “It was the perfect storm,” McCormick told me one day when we met in her office at Harvard. “Because all of a sudden we had the expansion of shots, the issue of the mercury in vaccines, and this rapid rise in the diagnosis of autism. Everyone put two and two together and came out with six.” In a society where numeracy is rarely prized and subjective decisions often outweigh rational choices, it’s not hard to understand at least some of the reasons why that happened: science works slowly and has yet to determine a cause for autism, which isn’t even a single “disease,” but rather a complex set of developmental disorders. In fact, it makes no more sense to talk about “curing” autism than it does to discuss a cure for cancer; “cancer” is an umbrella term for many diseases characterized by malignant growth. A successful treatment for leukemia won’t stop the spread of melanoma. Effective treatments for autism will require a fuller understanding of how those developmental disorders differ—but they can differ widely. Autism spectrum disorders vary in severity from mild conditions like Asperger’s syndrome to those characterized by sustained impairments in social interaction and communication abilities.

When “experts,” often with degrees or licenses that seem impressive, suddenly emerge to tell heartbroken family members that there is a simple solution to their problems, who wouldn’t want to believe it might be true? And with the help of the Internet, those experts are just a mouse click away. People often cling to their initial response when they discover something profoundly disturbing, even if more compelling evidence emerges. It’s a form of denialism, but also a common human instinct. Not surprisingly, then, the vaccine panel was indeed “pummeled” during its deliberations. Attacks came by e-mail and over the telephone. One member was effectively forced to resign after he received an escalating series of personal (and credible) threats that eventually became so worrisome that McCormick agreed to shift the venue of the committee’s final public meeting to a room where the members would be able to come and go in safety, interacting with the audience behind a human moat of security guards. Like a jury deciding the fate of a gangland leader, committee members were encouraged to stay in a single hotel, discuss the location with no one, and refrain from wandering about town on their own. Security was tightened; all this before the committee made its final report. When it came time for the meeting, each member was loaded onto a bus and driven directly to a garage beneath the main building of the National Academy of Sciences. That way, they could make it to the hearing room without having to run the gauntlet of protestors.

THE REPORT,
Vaccines and Autism
, was issued in May 2004. After an exhaustive analysis of the available data, and after review by another independent panel, the committee concluded that there was no evidence to suggest the existence of any relationship between the two. “There really wasn’t any doubt about the conclusions,” McCormick said. “The data were clear.” The Institute of Medicine team attempted to review every important epidemiological study, whether published or not, involving hundreds of thousands of children in several countries. They set out with a clear goal: to discover what biological mechanisms involved in immunizations might cause autism. Yet, no matter where they looked or how they parsed the data, the central results never varied: unvaccinated children developed autism at the same or higher rate as those who had been vaccinated. The panel reported accordingly: “The committee concludes that the body of epidemiological evidence favors rejection of a causal relationship between the MMR vaccine and autism.”

The report also pointed out that the mercury contained within the preservative thimerosal, which had been used widely in vaccines for nearly seventy years, caused no apparent harm. Thimerosal had been a focus of special fury among anti-vaccine activists. By July 1999, however, two years before the IOM committee was convened, the preservative had been ordered removed from childhood vaccines as a precautionary measure. Vaccine manufacturers, under fierce public pressure, had agreed with the Centers for Disease Control and the American Academy of Pediatrics. “Parents should not worry about the safety of vaccines,” the academy said at the time. “The current levels of thimerosal will not hurt children, but reducing those levels will make safe vaccines even safer. While our current immunization strategies are safe, we have an opportunity to increase the margin of safety.” In other words, they decided it would be easier to get rid of the controversy than to explain it.

The decision, an attempt to placate parents, had no basis in scientific research, and set off a cascading wave of misunderstanding that persists to this day. Almost immediately, advocacy groups arose, filled with members who were convinced thimerosal had caused their children’s autism. “It was a decision that was made very abruptly,” McCormick, who had no role in making it, told me. “And with not very good communication between professionals and the public. Maybe they should have thought about what you might want to know to reassure people and that is a valid concern of parents. You know how this looks: ‘Last year you told me this was safer than blazes, and this year you are taking it out of the drinking water. Hmm . . . how can I possibly trust a word you say?’ ” At the time, little was known about the toxicity of ethyl mercury, the chemical compound in thimerosal—so almost all toxicology data about mercury in vaccines was inferred from research into a related molecule, methyl mercury, which is found in fish that we eat and is used heavily in industry. While everyone has tiny amounts of methyl mercury in their bodies, the less the better, particularly because it can take months to be eliminated from our tissues.

The IOM examined the hypothesis that vaccinated children would develop a particular type of autism, caused by mercury poisoning. Presumably those children would develop symptoms at a different age than those who were not vaccinated. Yet in an analysis of tens of thousands of children, no statistical age difference was discovered. Furthermore, if, as so many parents and advocacy groups still believe, there is a link between thimerosal and autism, one would assume that the number of children diagnosed with the illness would have decreased rapidly after the middle of 2000, by which time the preservative had been removed from nearly every childhood vaccine. Researchers in Montreal had a unique opportunity to test this hypothesis because in the 1980s Canada began to phase out thimerosal slowly over a decade. As a result, Canadian infants born in the years between 1987 and 1998 could have received nearly any amount of thimerosal in vaccines, from none to 200 micrograms, the latter being nearly the maximum daily dose that had been permitted in the United States. The Canadian team was able to study discrete groups and found that autism was most prevalent among children who received vaccines that contained no mercury.

Epidemiologists in Finland pored over the medical records of more than two million children, also finding no evidence that the vaccine caused autism. In addition, several countries removed thimerosal from vaccines before the United States. Studies in virtually all of them—Denmark, Canada, Sweden, and the United Kingdom—found that the number of children diagnosed with autism continued to rise throughout the 1990s, after thimerosal had been removed. All told, ten separate studies failed to find a link between MMR and autism; six other groups failed to find a link between thimerosal and autism. It is impossible to prove a negative—that a relationship between thimerosal and autism does not exist. While data can’t prove that, it has failed to find any connection between them in any significant study. Because of the strength, consistency, and reproducibility of the research, the notion that MMR or thimerosal causes autism no longer seemed to public health officials like a scientific controversy.

The panel attempted to be definitive: “The committee also concludes that the body of epidemiological evidence favors rejection of a causal relationship between thimerosal-containing vaccines and autism. The committee further finds that potential biological mechanisms for vaccine-induced autism that have been generated to date are theoretical only. The committee does not recommend a policy review of the current schedule and recommendations for the administration of either the MMR vaccine or thimerosal-containing vaccines.” The report suggested that people forget about thimerosal (which by then remained only in certain flu vaccines) and the controversy behind it. After all the research, thimerosal may be the only substance we might say with some certainty
doesn’t
cause autism; many public health officials have argued that it would make better sense to spend the energy and money searching for a more likely cause.

It didn’t take long for the findings, and the finality with which they were delivered, to generate reactions. Boyd Haley, professor of chemistry at the University of Kentucky and a witness who has often testified about his beliefs that mercury in thimerosal caused autism, was “amazed and astounded” that the IOM would conclude otherwise. Haley is also a prominent “amalgam protestor,” convinced that trace amounts of mercury in dental fillings cause Alzheimer’s disease, although no data exists to support that view. “The dismissal of thimerosal as causal to autism is outrageous!” he said. “It reflects a level of ignorance that is unacceptable for a scientific review committee. This is disgraceful and puts into question the very credibility of every oversight government authority in the United States. Exposure to thimerosal (mercury) causes a biochemical train wreck. I’m flabbergasted.”

His was far from a lonely voice of outrage. The day the 2004 report was released, Indiana representative Dan Burton erupted. “This research does a disservice to the American people,” he stated. Burton had long been a vociferous critic of the public health establishment and was well known for doubting many of the tenets of conventional medicine. “My only grandson became autistic right before my eyes—shortly after receiving his federally recommended and state-mandated vaccines,” he said in 2002. In an October 25, 2000, letter to the Department of Health and Human Services, acting in his role as chairman of the House Committee on Government Reform, Burton asked the agency’s director to force the Food and Drug Administration to recall all vaccines containing thimerosal. “We all know and accept that mercury is a neurotoxin, and yet the FDA has failed to recall the 50 vaccines that contain Thimerosal,” Burton wrote, adding, “Every day that mercury-containing vaccines remain on the market is another day HHS is putting 8,000 children at risk.” (The letter was sent more than a year after voluntary withdrawal turned exposure to thimerosal, which remained in only some flu vaccines, into a rarity.)

It would be easy enough, and to many people comforting, to dismiss Burton as a fringe figure—his active indifference to scientific achievement and his opinions on health matters are highly publicized and widely considered ludicrous. If he is a fringe figure, however, he has unique power and many followers. The controversy not only continued, but intensified. Politicians have not shied away from using thimerosal as a public relations tool. On September 28, 2004, Arnold Schwarzenegger, governor of California, banned thimerosal-containing vaccines from his state for children and pregnant women. Other states soon did so as well.

No prominent American has spoken with more conviction about the putative dangers of vaccines or their relationship to autism than Robert F. Kennedy Jr. To him, the IOM report proved only that “the CDC paid the Institute of Medicine to conduct a new study to whitewash the risks of thimerosal,” he wrote in 2005, “ordering researchers to ‘rule out’ the chemical’s link to autism.” That year, Kennedy, whose environmental work for the Hudson Riverkeeper organization has often been praised, published an article in
Rolling Stone
(and on the Internet at
Salon.com
) called “Deadly Immunity.” It was, he wrote, “the story of how government health agencies colluded with Big Pharma to hide the risks of thimerosal from the public . . . a chilling case study of institutional arrogance, power and greed. . . . I was drawn into the controversy only reluctantly. As an attorney and environmentalist who has spent years working on issues of mercury toxicity, I frequently met mothers of autistic children who were absolutely convinced that their kids had been injured by vaccines.” He went on to say that he was skeptical until he read the scientific studies and looked at the data.

“Deadly Immunity” was a landmark in the history of science journalism, combining Kennedy’s celebrity star power with a stinging assault on reason and scientific fact. The piece was riddled with inaccuracies, filled with presumptions for which there was no supporting data, and knit together by an almost unimaginable series of misconceptions. Kennedy largely framed his piece around quotes taken from the transcripts of a scientific meeting where members of the Immunization Safety Review Committee had gathered to plan their work. Those quotes appeared particularly to damn Dr. McCormick, the committee leader. According to Kennedy’s article, McCormick told her fellow researchers when they first met in January 2001 that the CDC “wants us to declare, well, that these things are pretty safe,” and “we are not ever going to come down that [autism] is a true side effect” of thimerosal exposure. In other words, before the committee even began its work, Kennedy asserts, McCormick had closed her mind to the possibility of a connection between thimerosal and autism. It was exactly the kind of conspiracy people concerned about the effects of the MMR vaccine had feared.