[Autism and vaccinations: the end?]

Of the different theories explaining the aetiology of autism, one that has achieved widespread popularity among the general public is the involvement of the MMR vaccine as the causation of autism. The connection between vaccines and autism rests upon two theories. On the one hand, the anti-measles fraction of the vaccine is attributed with the development of an enteropathy due to malabsorption, which would facilitate the absorption of toxic neuropeptides and the effects of this process on the brain would favour the appearance of autism. The other theory involves thimerosal (a combination of ethylmercury and thiosalicylate), which is used as a preservative in some vaccines, including the MMR. The data in favour of these hypotheses have led to a great amount of social alarm, especially in certain areas that are more inclined to accept 'alternative' therapies and hypotheses.

This article analyses the data on which the involvement of the MMR vaccine in autism is based. It also underlines the weakness of the anti-vaccine arguments, as well as the forceful, convincing response, based on experimental and epidemiological work, that has been generated following the notable social unrest. Running parallel to the scientific debate, there has also been a legal discussion, which has arisen as a consequence of the more than 5,000 lawsuits filed in the United States, and in which the claims for financial compensation together amount to two thousand million dollars. On 12th February 2009, following a court hearing in which the specific case of a girl called Michelle Cedillo was taken as an example, the court ruled that the overall weight of the evidence was overwhelmingly opposed to the theories put forward by the plaintiffs.