Born 17 May 1749 at Berkley Gloucestershire, a country Doctor who make the connection between the less harmful cow pox and the dangerous small pox. His observations on milkmaids and other dairy workers that if they had cow-pox they did not get small pox. In a giant leap of faith he inoculated a farm hands son with cow pox then gave him small pox. The boy survived and inoculations have been with us since.
OTD Edward Jenner
Enquiring Minds and Ingenious Mechanics 