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Edward Jenner was the first person to develop a smallpox vaccine using the milder but still protective cowpox virus in 1798 . However, the practice of immunization dates back a great deal further. Variolation was first introduced to Europe in the 18th century, but it was used in non-Western cultures as early as 1000 B.C. Variolation involves blowing dried smallpox scabs into the nostrils of a healthy person to inoculate them with the infectious material from an infected person's "pox." People who had been inoculated would typically contract a mild form of the disease but would recover and develop immunity to smallpox Only 2% of people who were variolated died from smallpox, compared to a natural death rate of 14% . However, there were risks associated with this method; some people did pass away from variolation, and because it caused real infections, people who were inoculated could spread the disease.
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