Vaccines and autism and nonsense, oh my!
For today, I am going to tackle only one issue: the oft-repeated idea that vaccines cause autism.
No, they don’t. But don’t take my word for it. Keep reading. The genesis of this theory is of course the (in)famous Lancet paper written by Andrew Wakefield and colleagues back in 1998, which suggested that the MMR vaccine was causing autism. The disgrace of this paper and the ensuing nonsense it spurred has been covered in detail elsewhere, including Seth Mnookin’s fine book “The Panic Virus” as well as Ben Goldacre’s “Bad Science”. In short, the original paper was pretty crappy, Wakefield over-interpreted its results beyond any scintilla of credibility, and it’s since been retracted. As a final touch, Wakefield has been struck off of the Medical Register of the United Kingdom.
Since the publication of the fraudulent Lancet paper, many large studies of MMR and autism in humans have been conducted. None, not a SINGLE study, has shown that vaccines are related to this disease.
Here is a sampling of the studies conducted and the conclusions of the authors, with which I agree having read the papers.
Kaye et al., Mumps, measles, and rubella vaccine and the incidence of autism recorded by general practitioners: a time trend analysis. BMJ. 2001 Feb 24;322(7284):460-3.
“Because the incidence of autism among 2 to 5 year olds increased markedly among boys born in each year separately from 1988 to 1993 while MMR vaccine coverage was over 95% for successive annual birth cohorts, the data provide evidence that no correlation exists between the prevalence of MMR vaccination and the rapid increase in the risk of autism over time. “
Dales et al., Time trends in autism and in MMR immunization coverage in California. JAMA. 2001 Mar 7;285(9):1183-5.
“These data do not suggest an association between MMR immunization among young children and an increase in autism occurrence.”
Madsen et al., A population-based study of measles, mumps, and rubella vaccination and autism. N Engl J Med. 2002 Nov 7;347(19):1477-82. This study was conducted in over 500,000 children.
“This study provides strong evidence against the hypothesis that MMR vaccination causes autism.”
The evidence provided by the downfall of Wakefield and by these papers led the smarter of those in the anti-vaccine movement to understand that the MMR-autism link was complete bunk. However, having painted themselves into an anti-vaccine corner, they decided to target a new concept. Now, it’s not MMR at all that is causing autism, but rather the preservative thimerosal! Scary rants about mercury in vaccines abounded on the internet and on TV, thus terrifying innocent parents who were trying to make informed decisions about their children’s health. Fortunately, science came through again with some well-conducted studies showing NO LINK BETWEEN THIMEROSAL AND AUTISM.
Hviid et al, Association between thimerosal-containing vaccine and autism. JAMA. 2003 Oct 1;290(13):1763-6.
“The results do not support a causal relationship between childhood vaccination with thimerosal-containing vaccines and development of autistic-spectrum disorders.”
Heron et al., Thimerosal exposure in infants and developmental disorders: A prospective cohort study in the United Kingdom does not support a causal association. Pediatrics. 2004 Sep;114(3):577-83.
“We could find no convincing evidence that early exposure to thimerosal had any deleterious effect on neurologic or psychological outcome.”
Madsen et al., Thimerosal and the occurrence of autism: Negative ecological evidence from Danish population-based data. Pediatrics. 2003;112:604-6.
“The discontinuation of thimerosal-containing vaccines in Denmark in 1992 was followed by an increase in the incidence of autism. Our ecological data do not support a correlation between thimerosal-containing vaccines and the incidence of autism.”
Yet despite the copious amount of data showing that vaccines do NOT cause autism, some folks continue to irresponsibly promote this idea, much to the detriment of your health and that of your children. Your friendly neighborhood anti-vaccinator will assert that the studies I listed above are “flawed”. My advice is to ask them how the work is flawed and wait for the uncomfortable silence to waft over you. Follow it up by asking how Wakefield’s fraudulent study was less flawed than the ones above. In summary, the continued perpetration of the vaccine-autism link is a many-headed hydra that will take years to slay, and you have Wakefield to thank for that. Next up for my reader: why should YOU care if someone else doesn’t vaccinate their anklebiter?