So you know this as fact? That immunity is "only" built up by having "many" diseases?? I think a lot of people are just hung up on the whole idea that stabbing enough people with a virus offers immunity. I just happen to not believe in the theory that loading a kid down with multiple viruses shot directly into their blood stream is a smart idea to keep the kid healthy.
Having a disease, that's having a disease, will almost always confer future immunity on a person. This is a well known fact. Having had mumps, measles, and chickenpox, in most cases, makes one immune to contracting these diseases in the future. Being vaccinated against them does the same thing, WITHOUT having to actually have the debilitating, sometimes fatal disease.
Do you even know how the smallpox vaccination came about? It was noticed, by Jenner, that milkmaids never got smallpox. being constantly around cows, they would contract cowpox, which protected them. Hence he developed the smallpox vaccine, which has saved millions of people from death and/or disfiguration.
You're hijacking this thread, attempting to promulgate your own uneducated biases and ignoring hard cold known facts, out of hand. That isn't doing this thread, nor you, any good.
I have just one question for you................would you rather watch your child get a shot, or be seriously stricken with a horrendous disease, which could deform, blind, or kill them?