Sharly Attkisson is an Emmy award winning investigative journalist, formerly with CBS. In a new article she cites the many peer-reviewed medical journal articles suggesting links between vaccines and autism http://sharylattkisson.com/what-the-news-isnt-saying-about-vaccine-autism-studies/
I have a relative who works for a local branch of the Health Department. It's pretty much considered common knowledge to employees of the department that vaccines have caused neurological problems. As severe at autism? I don't know, but there are issues with vaccines. The question is one of cost/benefit analysis. Do any potential problems of vaccines outweigh the issues that would arise if everyone stopped getting vaccinated? Most would probably say yes, which is why the issues that have occurred are being minimized publicly.
It's not an issue that can be thrown out there delicately. Can you imagine a Health Department or CDC spokesperson saying "we think there might be some problems with vaccines, but we still prefer that you immunize your children". People would overract and it would be the same as giving a definitive statement.