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
1947 New York City smallpox outbreak Bar had developed a fever and pronounced rash. He was admitted to Bellevue Hospital, but because of the rash was transferred three days later to Willard Parker Hospital, a communicable disease hospital also in Manhattan. On admission to Willard Parker, the differential diagnosis was drug reaction (since Le Bar had reported taking proprietary headache powders and aspirin), erythema multiforme, Kaposi's varicelliform eruption, and smallpox. However, because Le Bar had a smallpox vaccination scar, an atypical rash, and no history of exposure, smallpox was immediately ruled out. A biopsy of the skin lesions did not reveal the Guarnieri bodies characteristic of