Jano Blonski
Jano Blonski voted up Didge Doo's answer

There are occasional (allergic?) reactions to vaccines that do indeed cause grave problems. Even so, the likelihood of reacting to the vaccine is far less than the chance of contracting the disease if the vaccination is refused -- as you implied in your question.

Jano Blonski
Jano Blonski voted up Veronica Dultry's answer

When my daughter was 16 she had 3 vaccinations at the same time. Within hours she had a complete psychotic break, that she still is not quite healed from. It took her a year to come back to us, and she still has physical disabilities.

Even with that, I still believe in vaccinations for all.