History of smallpox centuries, the WHO certified the global eradication of smallpox in December 1979. Smallpox is one of two infectious diseases to have been eradicated, the other being rinderpest, which was declared eradicated in 2011. It has been suggested that smallpox was a major component of the Plague of Athens that occurred in 430 BCE, during the Peloponnesian Wars, and was described by Thucydides. Galen's description of the Antonine Plague, which swept through the Roman Empire in 165–180, indicates that it was probably caused by smallpox. Returning soldiers brought the disease home with them to Syria and Italy, where it raged for
Extinction agreed with the prediction that up to 20% of all living populations could become extinct within 30 years (by 2028). A 2014 special edition of "Science" declared there is widespread consensus on the issue of human-driven mass species extinctions. Biologist E. O. Wilson estimated in 2002 that if current rates of human destruction of the biosphere continue, one-half of all plant and animal species of life on earth will be extinct in 100 years. More significantly, the current rate of global species extinctions is estimated as 100 to 1000 times "background" rates (the average extinction rates in the evolutionary time