The challenge
Smallpox killed up to 30% of the people it infected and had caused millions of deaths.
The case
In 1967 the World Health Organization launched an intensified plan to eradicate smallpox, combining widespread vaccination with surveillance to find outbreaks. Within four years the campaign had wiped out smallpox in Latin America. The last known natural case was in Somalia in 1977. In December 1979 an independent Global Commission of scientists from 19 nations certified that smallpox had been eradicated, and in 1980 WHO declared it eradicated.
Why it worked
An intensified global campaign of vaccination and surveillance ended a disease that had killed millions. It remains the only human infectious disease ever eradicated.
Sources
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