The first time I questioned vaccinations was before it was cool. My daughter's class had a Whooping Cough outbreak, the media blamed it on the unvaccinated kids.
However there were 8 confirmed cases, 4 kids were vaccinated and 4 were not.
This was 20+ years ago. So, while health decisions should remain private, and I don't hold a strong opinion on other people's healthcare decisions, they certainly don't work the way people have been lead to believe.
AND, of course, those decisions should be left to parents, not the government. Thanks for the comments!