One of the most contentious issues surrounding autism is the question of whether vaccines can cause or contribute to the presence of autism spectrum disorders. Recently, a panel of scientists conducted a literature review of more than a thousand journal articles reporting on effects of vaccines, and found no evidence of a link between vaccines and autism. Here is a link to the story:
http://www.nytimes.com/2011/08/26/health/26vaccine.html?_r=1&ref=health
However, as the article states, these latest findings will not bring an end to the belief of those who believe that there is a correlation between vaccinations and autism spectrum disorders. For example of the debate regarding this issue, check out this message board from a Seattle Times article reporting on the aforementioned story. For many parents, this issue takes on emotional resonance, a resonance which cannot be quelled through an unemotional appeal from scientists and physicians.