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1721Reputable source · 2 sourcesWell documented

Variolation Spreads From Asia to Europe as Smallpox Prevention

Long before vaccines, deliberate infection with smallpox itself cuts death rates tenfold, and an ambassador's wife carries the practice from Constantinople to London

On the timeline · around 1721 · The Birth of Vaccination and EpidemiologyOld World Diseases, New World CollapseThe Birth of Vaccination and EpidemiologyVariolation Spreads From Asia to Europe as Smallpox Prevention1650167517001725175017751800

Quick facts

Method
Deliberate infection with matter from a smallpox pustule or scab
Documented Asian use
China (since at least 1695) and India (16th century)
Brought to England by
Lady Mary Wortley Montagu, 1721, after observing it in Constantinople
Mortality comparison
1-2% of those variolated died, versus about 30% for natural infection
Risk
Could cause death or spread full-strength smallpox to others

What happened

Variolation, deliberately infecting a healthy person with material from a smallpox pustule or scab to trigger a mild, controlled case of the disease, had been practiced in Asia for centuries before it reached Europe. China's Golden Mirror of Medicine, a 1742 text, described inoculation methods used there since at least 1695, typically by drying smallpox scabs and blowing the powder into a patient's nostril, while practitioners in 16th-century India worked pus from pustules directly into the skin. By 1700 the practice had also spread to the Ottoman Empire and parts of Africa. Lady Mary Wortley Montagu, wife of the British ambassador to the Ottoman court, observed variolation in Constantinople in 1717 and had her own son inoculated there. After returning to England, she pushed for a public trial: in 1721, at her urging and that of the Princess of Wales, condemned prisoners and orphaned children were inoculated as a test, and when they survived subsequent exposure to smallpox, members of the British royal family adopted the procedure themselves. Variolation cut smallpox mortality to an estimated 1 to 2 percent of those inoculated, against roughly 30 percent for people who caught the disease naturally.

Why it matters

Variolation proved, decades before anyone understood viruses or immunity, that deliberately triggering a mild version of a disease could protect against a severe one, the same logic Edward Jenner would later apply with cowpox instead of smallpox itself. It also remained genuinely dangerous: inoculated patients could die of the induced infection or spread full-strength smallpox to others while contagious, a risk that made Jenner's later cowpox method a clear improvement rather than a wholly new idea.

How we know

The U.S. National Library of Medicine's smallpox history exhibition documents the Asian origins and the 1721 English trial using period records including Hans Sloane's own 1755 account of the London inoculations; the practice's spread through India, the Ottoman Empire, and Africa by 1700 is corroborated by the World Health Organization's history of vaccination.

Sources

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