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,
Vaccination policy in conjunction with the Spanish Medicines Agency, outlines specifications for vaccination schedules and policies and provides a history of vaccination policies implemented in the past, as well as legislature pertaining to the public currently. Spain's Constitution does not mandate vaccination, so it is voluntary unless authorities require compulsory vaccination in the case of epidemics. In 1921 vaccination became mandatory for smallpox, and in 1944 the Bases Health Act mandated compulsory vaccination for diphtheria and smallpox, but was suspended in 1979 after the elimination of the threat of an epidemic. The first systematic immunization schedule for the provinces of Spain was