May 17th
Born 17 May 1749; died 26 Jan 1823 at age 73.
English physician and surgeon who discovered vaccination for smallpox. There was a common story among farmers that if a person contracted a relatively mild and harmless disease of cattle called cowpox, immunity to smallpox would result. On 14 May 1796 he removed the fluid of a cowpox from dairymaid Sarah Nelmes, and inoculated James Phipps, an eight-year-old boy, who soon came down with cowpox. Six weeks later, he inoculated the boy with smallpox. The boy remained healthy, proving the theory. He called his method vaccination, using the Latin word vacca, meaning cow, and vaccinia, meaning cowpox. Jenner also introduced the word virus.