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,
Cowpox it was recorded that Phipps did not receive a reaction from it. Although Jenner was not the first person to conceive the notion of cowpox protecting against the smallpox virus, his experiment proved the theory. This vaccination worked temporarily. It was later discovered that the cowpox vaccination only worked temporarily against the invasion of smallpox and the procedure would need to be repeated several times through ones' lifetime to remain smallpox free. In later years, Jenner popularized the experiment, calling it a vaccination from the Latin for cow, vacca. The amount of vaccinations among people of that era increased drastically.