Smallpox is thought to have originated in India or Egypt at least 3,000 years ago. The earliest evidence for the disease comes from the Egyptian Pharaoh Ramses V, who died in 1157 B.C. His mummified remains show telltale pockmarks on his skin.

What animal does smallpox come from?

Smallpox is an acute, contagious disease caused by the variola virus, a member of the genus Orthopoxvirus, in the Poxviridae family (see the image below). Virologists have speculated that it evolved from an African rodent poxvirus 10 millennia ago.

How does smallpox begin?

Smallpox is caused by infection with the variola virus. The virus can be transmitted: Directly from person to person. Direct transmission of the virus requires fairly prolonged face-to-face contact.