Smallpox

The fall of smallpox began with the realization that survivors of the disease were immune for the rest of their lives. This led to the practice of variolation- a process of exposing a healthy person to infected material from a person with smallpox in the hopes of producing a mild disease that provided immunity from further infection the first written account of variolation describes a Buddhist nun practicing around 1022 to 1063 AD. By the 1700s, this method of variolation was common practice in China, India, and Turkey. In the late 1700s, European physicians used this and other methods of variolation but reported "devastating" results in some cases. Overall, 2% to 3% of people who were variolated died of smallpox, but this practice decreased the total number of smallpox fatalities by 10-fold.