This little gem is a 52 page digitized book by Alfred R. Wallace, LL.D.
The study was done for the years 1838 through 1882. Except for sounding a little archaic in parts, this sentence from the first paragraph hits on today's issues:
"The question is one which affects our personal liberty as well as the health and even the lives of thousands; it >therefore becomes a duty to endeavour to make the truth known to all, and especially to those who, on the faith >of false or misleading statements, have enforced the practice of vaccination by penal laws."
Read the book here:
https://archive.org/stream/b2136140x#mode/2up
The science is settled. Right. There is nothing new under the sun.