The idea that vaccines are a primary cause of autism has been around for some time. The idea took off in the 1990′s when Andrew Wakefield claimed that the MMR was causing autism, including suggesting that not only was MMR causing autism but was responsible for the rise in diagnoses observed. Later, the idea that the increase in thimerosal exposure in the pediatric vaccine schedule of the 1990′s in the US was proposed by some groups as causing the increase in diagnoses. Both ideas have since been shown to be invalid. As the evidence mounted that the idea that thimerosal and/or MMR caused an autism epidemic was false, the idea that the increase in vaccines themselves was causing autism. This idea was popularized by Jenny McCarthy of Generation Rescue in the slogan “too many too soon”. The study is in the journal Pediatrics (full version available free): Increasing Exposure to Antibody-Stimulating Proteins and Polysaccharidesin Vaccines Is Not Associated with Risk of Autism .
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