Originally Posted by rabrog
My comeback to the statement in the title is always "then why, during recent outbreaks, have the majority of infected kids been vaccinated against the outbreak disease?" No one can answer that.
The line of thought is that the diseases are coming back because not enough people are vaccinating, nullifying herd immunity. This makes people who have been vaccinated at risk for the disease, as vaccines are never 100% effective.
Proportionally, the unvaccinated usually are more represented in an outbreak. If you have a 80% vaccination coverage, and you have 70% of the people in the outbreak vaccinated, the vaccine still worked. You would have a better chance of being protected from the disease if you had been vaccinated (depending on how effective the vaccine is).
Some vaccines are 95% effective and others are as low as 60% in an outbreak (which begs the questions as to how you can ever create herd immunity with some vaccines. If you have a 60% efficacy, even with 100% coverage, you won't get to the +- 80 - 90 % needed for herd immunity).
I believe that some diseases would come back in full force, and others wouldn't if we stopped vaccinating on a mass scale.