smallpox
in 1796,
Through a cow
Edward Jenner did not discover germs, he developed vaccination for smallpox (using cowpox pustules) which was much safer than the inoculation for smallpox (using smallpox pustules) then in use. However he had no idea what actually caused smallpox, only that it was something invisible in the pus from the pustules.
it was edward Jenner
cows
No
the smallpox vaccine.
The discoverer of this particular vaccine was Edward Anthony Jenner. The first time it was used was in 1796 in England.
smallpox
Edward Jenner.
Edward Jenner