What is the status of research into associations between vaccines and the autism spectrum of disorders?
All credible evidence has shown absolutely no association between any vaccine and autism. There also was, for a time, concern about thimerasol, a mercury-containing preservative in vaccines. Earlier in this decade, thimerasol was taken out of all vaccines in the U.S. except for some viral influenza vaccines. However, we have not seen autism rates fall as we’d expect if in fact autism was due to this preservative. Further, thimerasol had been removed from vaccines in Europe a decade prior, yet the reported rates of autism there still increased in a fashion similar to those in the U.S. The idea that certain vaccines have been linked to mental illness of any type has been around for several decades; all that changes is which vaccine gets blamed for those problems. In the 1970s and into the 1980s, some believed the DPT vaccine (diphtheria, pertussis, tetanus) caused mental damage or brain damage. Once those links were disproven, different theories arose. The theory most common in the 1990s
