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,
Mozart and smallpox wrote, 'the most terrible of all the ministers of death.' Those who survived smallpox did not always survive intact; it frequently inflicted blindness on its survivors. The survival rate was particularly low for children. The physical appearance of the disease was frightening to patients and to their caretakers: the patient's skin became covered with large, bulging pustules, which often left conspicuous pitting on the skin of patients who survived the disease. Medicine had made only slight progress against the disease in Mozart's time. Around the second decade of the 18th century the method of inoculation, which had originated in Asia,