Disability Resource Directory

Cause of Autism Part III

Vaccine theory

Controversial research by Andrew Wakefield in the UK that was published in The Lancet in the February 1998 issue, dubbed the "Wakefield Study", suggested a possible link in cause of autism and the MMR vaccine. The original research has come under criticism, largely due to an alleged conflict of interest on Wakefield's part. In March 2004, almost all of the paper's authors retracted its "interpretation" section, which claimed a potential link between pervasive developmental disorders and "possible environmental triggers".

Critics have claimed that Wakefield's study contains many obvious flaws, including an inability to recognize bias in his sample. In October 2005, a study by the respected Cochrane Library said, on the basis of 31 pieces of research into the possible side effects of MMR, that it found no association between MMR and autism. Several independent groups, including the National Academy of Sciences, have also conducted investigations and concluded that the evidence does not support a link.

One study by Gillberg and Heijbel in 1998 examining the prevalence of autism in children born in Sweden from 1975 to 1984 found no difference in the prevalence of autistic children born before the introduction of the MMR vaccine in Sweden and those born after the vaccine was introduced. Another study, conducted by Madsen and other researchers in 2002, studied all children born in Denmark from January 1991 through December 1998. There were a total of 537,303 children in the study; 440,655 of the children were vaccinated with MMR and 96,648 were not. The researchers did not find a higher risk of autism in the vaccinated than in the unvaccinated group of children.

Research in the U.S. has suggested a similar link between autism and the DPT vaccine, although this is not referenced. However, contrary to early claims from Wakefield, it is doubtful that a large majority of autism cases would come from this vaccine. Despite all the evidence to the contrary, controversy surrounding autism and vaccines continues to this day, and many polls, such as the autism coach poll, which involved only 15 respondents, show vaccines as the most popular theory currently on the etiology of autism among parents of autistic children.

Dr Mark Geier and his son, David Geier have published eleven peer-reviewed studies on the possible link between autistic spectrum disorders and childhood vaccines (TCVs). In their first study, they compared the number of complaints associated with TCVs, administered between 1992 and 2000, to the number of complaints resulting from a thimerosal-free vaccine administered between 1997 and 2000. The children who received greater amounts of ethylmercury from TCVs were more likely to have a complaint filed with the Vaccine Adverse Event Reporting System (VAERS). Further studies by the Geiers yielded similar results. In 2006, the Geiers published an article , "Early Downward Trends in Neurodevelopmental Disorders Following Removal of Thimerosal-Containing Vaccines", which contends that recent data confirms a reduction in autism diagnoses corresponds directly with the removal of TCVs from childhood vaccination schedules.

US health agencies have uniformly rejected the conclusions of the Geiers' studies, and one of the Geiers' articles was the subject of heavy criticism by the American Academy of Pediatrics. Geier says public health officials are "just trying to cover it up."

On the other hand, a report prepared by the staff of the Subcommittee on Human Rights and Wellness, House Committee on Government Reform, Chaired by Dan Burton, was published in the Congressional Record in May, 2003, stated:

"However, the Committee upon a thorough review of the scientific literature and internal documents from government and industry did find evidence that thimerosal did pose a risk. Thimerosal used as a preservative in vaccines is likely related to the autism epidemic. This epidemic in all probability may have been prevented or curtailed had the FDA not been asleep at the switch regarding the lack of safety data regarding injected thimerosal and the sharp rise of infant exposure to this known neurotoxin. Our public health agencies’ failure to act is indicative of institutional malfeasance for self-protection and misplaced protectionism of the pharmaceutical industry."

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