Ali Maow Maalin in Somalia had the last natural case of smallpox in 1977. After a global immunization plan organized by the World Health Organization, the disease was declared eradicated in 1980.
Smallpox was one of the most devastating and debilitating diseases in human history. It kills 30 percent of those infected, and it’s highly contagious. An estimated 300 million people died of smallpox in the 20th century alone. Only two known samples of the virus that causes smallpox exist: One is in the high containment lab at the Centers for Disease Control in Atlanta, and the second is in the Russian State Research Center for Virology and Biotechnology in Koltsovo in Novosibirsk, Russia. Now, global warming is thawing permafrost soils, potentially releasing long-frozen pathogens like smallpox.