A common vaccine given to children to protect them against measles, mumps and rubella is not linked to autism, a study published yesterday concludes.
From the Washington Post:
The findings contradict earlier research that had fueled fears of a possible link between childhood vaccinations and a steep increase in autism diagnoses. In February 1998, the Lancet journal published a study by British researcher Andrew Wakefield of 12 children with autism and other behavioral problems that suggested the onset of their behavioral abnormalities was linked to receiving the MMR (measles, mumps, rubella) vaccine.
The new study comes as the U.S. Court of Federal Claims in Washington is in the midst of evaluating evidence on whether children's vaccines are implicated in causing autism. A special master is evaluating three different kinds of claims -- two of which specifically link the MMR vaccine with autism.
From the Los Angeles Times:
Led by scientists at the Columbia University Mailman School of Public Health, the research team took bowel tissue samples from 25 children with autism who had gut disturbances and compared it to bowel tissue of 11 children who also had such disturbances but did not have autism. The researchers screened the tissue for presence of the genetic material of the measles virus to see if the virus persisted more often in the children who had developed autism. Three labs examined the tissue independently, and no one knew which tissue came from autistic or non-autistic children until after the results were in. In all three labs, only two of the samples showed traces of the measles virus. One was from a child in the autism group and one was from a child without autism.
In other words, children with autism were no more likely to have measles virus in their tissue than ones who did not have autism, and that doesn't support a MMR-autism causal link, the authors concluded.
The scientists also investigated the temporal relationship you'd expect if the vaccine-autism theory were true. If the vaccine caused gut symptoms/autism, you'd expect the vaccine timing to precede either of the other two. This wasn't found.
The Autism Society of America cautioned that the cause of autism is complex and more research is needed to fully understand the role, if any, of a vaccine. Another autism advocacy group, the National Autism Association (NAA), has stated that the study is flawed.
Original source: http://kreuzer33.wordpress.com/?p=943
