Technology & Medicine › Printing & the scientific revolution › Vaccination (Jenner's smallpox vaccine)
Variolation (smallpox inoculation)
long used in Asia and Africa; England 1721· Invention or discovery· Germs, drugs & genetics
Mostly agreedGood evidence; some details, dates or numbers uncertain.
Deliberately infecting a healthy person with material from a smallpox sore to cause a mild case and lifelong immunity.
See it on the Technology & Medicine map →How it works
Healers in China blew powdered smallpox scabs up the nose; in India, Africa and the Ottoman Empire they scratched pus into the skin. The resulting illness was usually mild: about 1 to 2 percent died, versus roughly 20 to 30 percent with natural smallpox. Lady Mary Wortley Montagu brought the Ottoman method to England in 1721. That year in Boston, Cotton Mather, told of it by Onesimus, an enslaved West African man, promoted inoculation during an epidemic.
Why it mattered
It was the first deliberate way to prevent a deadly disease and proved immunity could be induced, paving the way for Jenner's safer cowpox vaccine in 1796.
Think of it like
Like a controlled burn: setting a small, managed fire to avoid a large, deadly one.
How we know
Chinese medical texts from 1549 onward, Ottoman and Royal Society reports from the 1700s–1720s, and Zabdiel Boylston's Boston figures: about 2 percent of inoculated patients died, versus about 14 percent of the naturally infected.
Still unknown or debated
Where and when variolation began, in China, India or Africa, is unknown; the story of a Song-dynasty nun inventing it around 1000 is a legend.
Connections (2)
▸Chinese medicine and acupuncture practised an early form of Variolation (smallpox inoculation)Mostly agreed
The connection
Chinese physicians practiced variolation by the 1500s: they dried scabs from mild smallpox cases, ground them into powder and blew it into healthy children's nostrils, fitting the Chinese idea of fighting poison with poison. Reports of the method reached Britain's Royal Society in 1700, two decades before inoculation spread in England.
When and how
China, first clearly described by Wan Quan in 1549 and detailed in texts of the 1690s; the Qing emperor Kangxi, a smallpox survivor, promoted it.
How sure are we?
Chinese medical books from 1549 onward describe the method, and letters to the Royal Society in 1700 report it; claims of Chinese variolation around 1000 are legends.
Debates and open questions
Whether the Chinese method influenced the Turkish and African skin-scratching methods that actually reached Europe, or arose separately, is unknown.
▸Variolation (smallpox inoculation) was replaced by safer Vaccination (Jenner's smallpox vaccine)Well documented
The connection
Variolation deliberately infected people with material from smallpox sores, usually causing a mild case and lifelong immunity, but it killed perhaps 1–2% and could spread smallpox. Jenner used cowpox, a mild cattle disease, instead. It protected with far less danger and could not start a smallpox outbreak. Britain banned variolation in 1840.
When and how
Variolation in China, India, Africa and the Ottoman Empire for centuries; Jenner in Berkeley, England, 1796; British ban, 1840.
How we know
Jenner was variolated as a boy and used variolation to test whether his vaccinated patients were immune, as his 1798 Inquiry records.
Debates and open questions
Variolation death rates are estimates and varied by method; how early variolation began in Asia and Africa is uncertain.