Autism AND VACCINES (developed by Veronique Bure)

The debate started in 1998, when Andrew Wakefield and his colleagues reviewed reports of children with Inflammatory Bowel Disease (IBD) and regressive developmental disorders, mostly within the Autism spectrum.  The researchers suggested that MMR (Measles/Mump/Rubella) vaccination led to intestinal abnormalities, resulting in impaired intestinal function and developmental regression.  Thus it was thought that the MMR vaccine could account for the increase of children diagnosed with autism in the past 15 years. Wakefield’s study involved only 12 children.  It is too few cases to allow generalization about autism and there were no healthy control children for comparison.  In 2004, 10 of the 13 authors of the 1998 study retracted the study's interpretation.  The authors stated that the data were not able to establish a causal link between MMR vaccine and Autism. 

In another study that generated media attention and raised public concern in the UK, and was conducted by Uhlmann et Al,  in 2002,  found measles virus fragments in the intestines of children with "new variant" IBD (children with both IBD and developmental disorder).  The researchers found measles virus fragments in 75 out of the 91 children with "new variant" IBD, and in only 5 of the 70 controls.  While this provides evidence for an association between the presence of measles virus and IBD in children with developmental disorder, it does not mean that the measles component of the MMR vaccine causes IBD or developmental disorder. 

Kaye and colleagues (2001) assessed the relationship between the risk of Autism among children in the UK and MMR vaccine.  Among a subgroup of boys aged 2-5 years, the risk of Autism increased almost 4 fold from 1988 to 1993, while MMR vaccination coverage remained constant at approximately 95% over these same years. 

The study involving the largest numbers of children was conducted by Madsen et Al. (2002) in Denmark from a data collection starting in 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. 

Other large studies in the US have found no link between autism and MMR vaccine. 

They were performed by groups having no connections with the pharmaceutical companies: such as the Institute of Medicine and the National Academy of Sciences.  These reviews have concluded that the available epidemiologic evidence does not support a causal link between MMR vaccine or vaccines that contain thimerosal (a mercury derivative) as a preservative and autism.  After four years of research the Immunization Safety Committee recommends that Thimerosal be removed from most of childhood vaccines to be on the safe side. 

More info on vaccines and autism at:

http://www.opinionjournal.com/editorial/feature.html?id=110004700

http://www.metrokc.gov/health/prevcont/autism.htm