Smallpox 1718. In 1721, Cotton Mather and colleagues provoked controversy in Boston by inoculating hundreds. In 1796, Edward Jenner, a doctor in Berkeley, Gloucestershire, rural England, discovered that immunity to smallpox could be produced by inoculating a person with material from a cowpox lesion. Cowpox is a poxvirus in the same family as variola. Jenner called the material used for inoculation vaccine, from the root word "vacca", which is Latin for cow. The procedure was much safer than variolation, and did not involve a risk of smallpox transmission. Vaccination to prevent smallpox was soon practiced all over the world. During the
Edward Jenner these cases the severity of the illness was notably diminished by previous vaccination. In 1821, he was appointed physician extraordinary to King George IV, and was also made mayor of Berkeley and justice of the peace. He continued to investigate natural history, and in 1823, the last year of his life, he presented his "Observations on the Migration of Birds" to the Royal Society. Jenner was found in a state of apoplexy on 25 January 1823, with his right side paralysed. He never fully recovered and eventually died of an apparent stroke, his second, on 26 January 1823, aged 73.