I come from an era when growing up there were adults unlucky enough to not have been vaccinated as children, they suffered the ill effects of some of these diseases and I watched these people struggle the rest of their lives with it. I think one thing that may be the problem with today's younger people, they never actually witnessed the deformities from such things as polio and the profound effect it had, if they had they know it wasn't no laughing matter watching people struggle in leg braces or spend their life walking around bent over.