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,
Smallpox from Kosovo returned from the Middle East, where he had contracted the virus. The epidemic infected 175 people, causing 35 deaths. Authorities declared martial law, enforced quarantine, and undertook widespread re-vaccination of the population, enlisting the help of the WHO. In two months, the outbreak was over. Prior to this, there had been a smallpox outbreak in May–July 1963 in Stockholm, Sweden, brought from the Far East by a Swedish sailor; this had been dealt with by quarantine measures and vaccination of the local population. By the end of 1975, smallpox persisted only in the Horn of Africa. Conditions were