In the latest issue of Discover, I have a major feature story exploring this question. Over a decade ago, activists began to raise doubts about the safety of the MMR vaccine, and all vaccines that containing the (now removed) mercury-based preservative thimerosal. Accordingly, scientists duly set out to examine whether these claims–centering on allegations that such vaccines were causing a tragic “epidemic” of autism–had anything to them.
Now, ten years later, the weight of evidence is overwhelming that vaccines are not guilty as charged. As I put it in the piece, summarizing the development of the science:
….even as vaccine hysteria reached a fever pitch in , the scientific evidence was leaning strongly in the other direction. In discounting the dangers of both the MMR vaccine and thimerosal, the [National Academy of Sciences' Institution of Medicine] had multiple large epidemiological studies to rely on. For MMR, the IOM examined 16 studies. All but two, which were dismissed because of “serious methodological flaws,” showed no evidence of a link. For thimerosal, the IOM looked at five studies, examining populations in Sweden, Denmark, the United Kingdom, and the United States (studies that vaccine critics contend were flawed). Since then, further research has strengthened and vindicated the committee’s original conclusion. It is a conclusion that has been “independently reached by scientific and professional committees around the world,” as a recent science journal commentary noted. Either the scientific community has found a clear, reassuring answer to the questions raised about thimerosal in vaccines, or there is a global scientific conspiracy to bury the truth.
The article then goes on to explore the true source of harm here (the vaccine skeptic movement and vaccine related misinformation, not the vaccine supply); the way vaccine skeptics have conveniently shifted their claims as earlier ones have been buried by scientific evidence; and perhaps most worrisome of all, how science and much of the public managed to fall so out of touch with one another on this critical public health question.
Once again, you can read the full piece here. I hope you enjoy it, and expect to see more pro-vaccine blogging at “The Intersection” from now on–not only because of this article, but because of our more general sense that the vaccine skeptic movement has now become one of the chief indicators that we do, indeed, live in an Unscientific America…..