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 survivors. In northern Japan, Ainu population decreased drastically in the 19th century, due in large part to infectious diseases like smallpox brought by Japanese settlers pouring into Hokkaido. The Franco-Prussian War triggered a smallpox pandemic of 1870–1875 that claimed 500,000 lives; while vaccination was mandatory in the Prussian army, many French soldiers were not vaccinated. Smallpox outbreaks among French prisoners of war spread to the German civilian population and other parts of Europe. Ultimately, this public health disaster inspired stricter legislation in Germany and England, though not in France. In 1849 nearly 13% of all Calcutta deaths were due to