We have no desire to downplay the impact of autism on the families and lives of children it affects. We have no desire to dissuade research into the causes of autism and why it appears to be more prevalent in recent years. However, we have to believe what science tells us, even when we dislike the results. Good science is based on widely accepted principles and methods; anecdotal evidence is not research. Believe us – we have no great love of the pharmaceutical industry, nor do we have any vested interest in keeping vaccines going. This book should stand as a testament to our scepticism of accepted wisdom. In this case, however, conventional wisdom appears correct. Science does not support a link between vaccines and autism.
The idea that vaccines cause autism began in 1998, when an article was published in The Lancet that followed the cases of twelve children with developmental regression and gastrointestinal symptoms, such as diarrhoea or stomach pain. Nine of those children had autism, and eight of the nine had parents who thought the symptoms of autism developed after the vaccine for measles, mumps and rubella (MMR) was administered. This was not a randomized controlled trial, or even a scientific study. It was merely a description of a small group of children. To be honest, it’s difficult to imagine such a study getting published in The Lancet today. Based on the described beliefs of those eight parents, a frenzy of fear about vaccines and autism has ensued for the past decade. Moreover, these concerns about autism and vaccines are only heightened by a timing issue. Remember, humans try to make sense of the world by seeing patterns. When they see a disease that tends to appear around the time a child is a year old (as autism does), which is also the age at which children get particular vaccinations, our human brains want to put those things together. But just because two things happen at the same time, one does not cause the other. This is why we need careful, scientific studies to answer important questions like this. There have been many such studies in the last decade that have contradicted the hypothesis that vaccines cause autism. These are just a few:
• In 1999, a study in The Lancet described almost 500 children with autism born in England after 1989. No difference was seen in the age of diagnosis for those who did and those who did not receive vaccines. This means that either there is no association between the MMR vaccine and autism or the association is so weak that it could not be detected in a large sample of children with autism.
• A 2001 study published in the Journal of the American Medical Association described data on over 10,000 kindergarten children in California from 1980 to 1994. The incidence of autism over that time (calculated from birth rates in California) increased over that time from 44 per 100,000 births to 208 per 100,000 births – a 373 per cent increase. The increase in MMR coverage, however, rose from 72 per cent to 82 per cent, a much smaller increase of 14 per cent. Thus the relatively small increase in children getting the MMR vaccine is too small to be responsible for the very large increase in autism.
• A 2002 study in the New England Journal of Medicine followed all children born in Denmark from 1991 to 1998. This means they obtained data on over 530,000 children born in those years. They could find no association between the development of autism and the age at vaccination, the time since vaccination or even the date of vaccination. (Just for the record, that is 530,000 children followed scientifically versus the beliefs of eight parents!)
• In 2005, a systematic review of studies examining the effectiveness and unintended effects of the MMR vaccine was published in the Cochrane Database. They identified 139 potential studies, and 31 met the criteria for their review. After a thorough investigation of these studies, even though the MMR could be associated with a number of side effects or other issues, they could find no evidence for an association between the vaccine and autism.
Even with overwhelming evidence to the contrary, people still claim that the jury is out about vaccines and autism. The recent case of Hannah Poling has reignited the debate. Hannah is a girl with an underlying mitochondrial enzyme deficiency who developed encephalopathy caused, her parents believe, by vaccinations. This encephalopathy led to long-term symptoms that fall under the autistic spectrum. After a great deal of effort, the Vaccine Injury Compensation Program, a US government program responsible for compensating patients who suffer from complications arising from vaccines, agreed to hear her case. This decision was not based on evidence. There is still no good body of scientific evidence to support this belief. However, the fact that the Vaccine Injury Compensation Program even agreed to hear the case was heralded by some as a concession by the government that vaccines may cause autism. To refute this, after a press conference to discuss the case, Julie Gerberding, the director of the Centers for Disease Control and Prevention, said, ‘The government has made absolutely no statement indicating that vaccines are a cause of autism [… t]hat is a complete mischaracterization of the findings of the case and a complete mischaracterization of any of the science that we have at our disposal today.’
Decisions such as this continue to fuel the efforts of those who believe that an association exists, even in the face of the scientific evidence. Unfortunately, unlike many of the myths described earlier in this book, believing this myth has potentially serious health consequences. Since this controversy began, many people have decided not to have their children immunized. As a result, more people are getting the diseases that vaccines prevent, sometimes with devastating consequences. Children can get very, very ill from measles, mumps or rubella. Sometimes they even die. Rachel works in Kenya for much of the year, and she routinely sees very ill children who are suffering precisely because they did not get vaccines. These diseases are still around, and as people travel more and more, children and adults in any country can be exposed to them. At least two million people of all age groups die every year from diseases that could have been prevented with existing vaccines.
Remember, this controversy all started ten years ago with a paper describing the beliefs of parents of eight children with autism. Since that time, ten of the twelve authors of that paper have publicly and professionally retracted from the original paper the supposition that MMR could cause autism; this is a rare occurrence in medical literature. An eleventh author could not be contacted before the release of the retraction in 2004. And the final author, who was the lead author of the original study, was investigated earlier this year for ethical violations, allegations of professional misconduct and undisclosed conflicts of interest in conducting that original research. The investigation is ongoing.
Imagine how different the world would have been if that one small study hadn’t been published.