Human history has been punctuated frequently by epidemics, and occasionally by pandemics, that have shaped the rise and fall of civilizations and the victories and defeats of warring armies. The outcome of the Peloponnesian War (431–404 B.C.E.) between Athens and Sparta—and the future course of Western civilization—might have been very different had it not been for the epidemic that decimated the Athenians at the beginning of the war. Some epidemic diseases, such as the plague, smallpox, typhus, and influenza, have persisted throughout recorded history. Smallpox was eradicated worldwide by 1980. Cholera appeared along the world's major trade routes in several devastating epidemics beginning in the eighteenth century, and it still causes massive epidemics, most recently in South America i...more >>n early 1990s.