jan 1, 1798 - Edward Jenner

Description:

Developed the smallpox vaccine.
Observed that people that come into close proximity with cows did not develop smallpox, they caught cowpox, a much milder version os small pox that did not kill.
Injected cowpox into an 8 year old boy then 6 weeks later Injected smallpox, the child did not develop smallpox.
He repeated this 16 times over several weeks and none of them reacted to inoculation.
Jenner knew cowpox protected people from smallpox but could not say why.
In 1853 smallpox vaccination was compulsory by the British Government.

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