My older brother and I were both fully vaccinated, with no issues, but for the last several years before she retired my mother did administrative work in a chiropractor's office. He was one of the anti-vaccination subluxation types and he was able to partly convert her. She's from an era when girls weren't expected to receive a science education, and she treated it as a shocking revelation that "when you get a vaccine they're injecting you with the disease", not knowing that's how the immune system works.
She also now likes to tell the story of a classmate from her childhood who "got the polio vaccine and then ended up in an iron lung", ignoring the possibility that she already had polio when she received the vaccine and hadn't developed symptoms yet, or the fact that it just wasn't 100% effective at the time.