Is Autism Linked To The MMR Vaccine?
Extract on Autism, taken from Wikipedia Autism is a brain development disorder that impairs social interaction and communication, and causes restricted and repetitive behavior, all starting before a child is three years old. This set of signs distinguishes autism from milder autism spectrum disorders (ASD) such as Asperger syndrome. Autism is highly heritable, although the genetics of autism are complex and it is generally unclear which genes are responsible.[1] In rare cases, autism is strongly associated with agents that cause birth defects.[2] Other proposed causes, such as childhood vaccines, are controversial and the vaccine hypotheses lack convincing scientific evidence.[3] Most recent reviews estimate a prevalence of one to two cases per 1,000 people for autism, and about six per 1,000 for ASD, with ASD averaging a 4.3:1 male-to-female ratio. The number of people known to have autism has increased dramatically since the 1980s, at least partly due to changes in diagnostic practic
