You could make an argument that vaccines are a problem when given too often, not allowing the body to respond with full force when necessary. I havnt seen much evidence of this one way or the other, but I dont work with them so my knowledge is mostly school based (which all seems to be slipping out the back of my head somehow).

You could also argue that they are teaching proper responses to foreign pathogens. Not every pathogen needs an A bomb response. Infact, as I am sure you know, many of our ‘diseases’ today are actually overzealous immune responses or immune systems not recognizing ‘self’. Alittle moderation on the immune systems part may be a prefered route.

With a population as large and varied as our human population today, I am sure you could come up with evidence for both.