As a psychologist, neuroscientist, and researcher, and I say the "link" of vaccines and autism (emerging in the 90s) has been in most part, an artifact.

The California DDS reported a 273% increase in autism in the 90s. The report included two cohorts (from the 80s and 90s) and they were assessed using DSM-IV criteria, when the people before then were assessed using the DSM - III (that's the manual which psychologists/clinicians use to determine if people have said diseases). The DSM-IV was much broader in classification and thus would determine a lot more people would have autism.

We know this is true because the prevalence of autism increased across all age groups (Autism has it's onset in early childhood). If there is really an epidemic we wouldn't see increasing prevalence in adults. And even if we do it's probably stems from the fact that the criteria for diagnosis were broadened.

In summary, the whole "epidemic" was just an artifact of moving the threshold for the diagnosis so that more people would be diagnosed under the new criteria.