What do the latest studies say about the MMR vaccine and autism?
Many people confuse the controversy over the vaccine for measles, mumps, and rubella with that of thimerosal, but the two have always been totally separate issues. In fact, MMR vaccines have never even contained thimerosal.
The link between MMR and autism gained traction following the publication of a very small British study (it only included 12 kids) published in a British medical journal, The Lancet. The study was lead by Dr. Andrew Wakefield and it concluded that children developed autism soon after they received the MMR vaccine. The theory: The measles portion of the shot causes inflammation and infection of the intestines, which can then spread dangerous proteins to the brain, causing damage that may lead to autism.
When this study was first published, it launched a frenzied debate that resulted in bigger, better-designed studies that have all failed to find any link between MMR and autism. However, by early 2010, The Lancet retracted Dr. Wakefield's research and by January 2011, the British Medical Journal publicly denounced Dr. Wakefield's research as "fraudulent," saying that he had "falsified data" and tampered with his research results to give the MMR vaccine bad publicity. At the time of his study, Dr. Wakefield had been involved in a lawsuit against the manufacturers of the MMR vaccine and would have gained money for winning, making his research an obvious conflict of interest.
Researchers suspect that parents may mistakenly associate the MMR vaccine with autism because signs of autism first appear around 12 to 15 months, which is also when the vaccine is first administered.