When Cortez's army brought smallpox from Europe to the Western Hemisphere, about 4 million Aztecs died from the disease. In the early part of the 18th century, Boston, a city of 10,000 people, suffered an epidemic of smallpox — 5,000 people were infected and 800 died from the disease. Indeed, smallpox has probably killed more people in the history of the world than all other infectious diseases combined! About 300 million people have died from smallpox. However, because of the smallpox vaccine, first developed in the late 1700s, smallpox has been eliminated from the face of the earth.
Reviewed by Paul A. Offit, MD, Lori Handy, MD, MSCE on May 01, 2017