Mozart and smallpox the imperial family were successful, and led to greater public acceptance for the procedure. Smallpox struck the Mozart family again in the next generation: Nannerl's eldest son Leopold and two of her stepchildren caught the disease during an outbreak in the Salzburg area in 1787. All three children survived. In 1796, the discovery of vaccination—the use of the related cowpox virus to immunize against smallpox—by Edward Jenner revolutionized the ability of medicine to deal with smallpox. Vaccination reached Vienna around 1800, when yet another local epidemic created impetus for its adoption. One of the doctors trained in the Vienna campaign,
History of smallpox a few small scratches on the arm of an eight-year-old boy who had never before contracted either smallpox or cowpox, named James Phipps. Phipps recovered as expected. Two months later, Jenner repeated the procedure using matter from smallpox, observing no effect. Phipps became the first person to become immune to smallpox without ever actually having the disease. He was variolated many more times over the course of his life to prove his immunity. When the next cowpox epidemic broke out in 1798, Jenner conducted a series of inoculations using cowpox, all of them successful except on his own son Robert.