Of course they do - as you could easily have discovered with thirty seconds and a GOOGLE search.
Most of the studies these days have to be done in "backwards" places like Bangladesh and Nigeria
http://www.who.int/bulletin/archives/80(10)776.pdf
where ignorant and superstitious people - sometimes because they have been told so by ignorant and superstitious religious leaders - sometimes believe that immunization is a government plot to harm their children
But if we keep going the way we are, we may again be able to start doing conducting their studies amongst Americans - just as it was possible in the 1970s to study several forms of childhood malnutrition that has disappeared in the US until moonbat Hippies put their young children on macrobiotic diets.
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Here's the bottom line:
“Oh never mind, they t keep these stats. I wonder why.
Of course they do ... “
You are using scare tactics in this thread. Nobody disputes the 20th century benefits. It’s only the last 20 years where money is dominating the agenda, not documented health benefits.
How about modern day info on the modern day disputable vaccines? Hepatitis, Chicken Pox, HPV, Meningitis. Where are these specs?