History of Smallpox: Earliest Evidence

The earliest credible descriptions of smallpox appear in Chinese medical texts from the 3rd century BCE (e.g., Huangdi Neijing references). Additional early evidence:

• Egyptian mummies (Ramses V, 1157 BCE): Pustular lesions consistent with smallpox — debated.
• Indian texts (Sushruta Samhita, ~400 CE): Describes "masurika" resembling smallpox.
• Persian physician Rhazes (9th century CE): First clear clinical differentiation from measles.

Global Impact

• Endemic in Eurasia/Africa by 1000 CE.
• Introduced to Americas 1520 → catastrophic mortality (up to 90% in some populations).
• Variolation (inoculation with live virus) practiced in China, India, Ottoman Empire → introduced to Europe 1721.
• Jenner's cowpox vaccine (1796) → global eradication campaign (1967–1980).
• Last natural case: Somalia, 1977. WHO declared eradication 1980.

Smallpox remains the only human disease eradicated by vaccination.