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What is WHO declared that smallpox has been eradicated in and explain in detail?
Smallpox is an acute contagious disease caused by the variola virus, a member of the ohopoxvirus family. It was one of the world&;s most devastating diseases known to humanity. The last known natural case was in Somalia in 1977. It was declared eradicated in 1980 following a global immunization campaign led by the World Health Organization.