Interesting. As a fomer special educator, I saw children who were autistic and perfectly happy just the way they were. I also saw children suffer. And I mean suffer - sensory overload, GI problems, injury from self-injury, near death experiences, abuse, etc.
My son would get sick after his vaccination rounds. So, about the time this whole HOLY CRAP! thing exploded, he was 3 or so. I decided to stop vaccinations. It was hard for me because he had RSV and asthma as a baby, so I kept wondering, "What if he gets whooping cough?" or some such.
But...I'm a pretty active and in tune parent, and my son has never had an illness that went unchecked, nor has he caught any illness that may have been prevented with a vaccination, flu not included.
So...the occurrence of polio is pretty much nil nowadays in the US.
It would be hard to imagine an epidemic unless it resurfaced and many many people were not vaccinated. (Which is why smallpox is scary, but the vaccine itself is dangerous and we don't use it anymore...getting OT here.) Anyway, I decided it was safer to NOT continue with vaccinations and watch my son get sick and have asthma attacks...now that he's older, if he were required to have them, I wouldn't object. I'll probably let him get the meningitis vaccine since we're in CO and he's at that age.