Who developed the first smallpox vaccine?
Quick answer
English doctor Edward Jenner developed the first successful smallpox vaccine in 1796. He used material from cowpox, a mild disease, to protect a boy named James Phipps from smallpox. The word “vaccine” comes from the Latin vacca, meaning “cow.” Smallpox was declared eradicated in 1980.
The milkmaid clue
Jenner noticed a local belief in the English countryside: milkmaids who caught cowpox from cows rarely got smallpox, a deadly disease that killed about 30% of those infected and scarred many survivors.
The 1796 experiment
- In May 1796, Jenner took material from a cowpox sore on the hand of milkmaid Sarah Nelmes.
- He scratched it into the arm of James Phipps, the 8-year-old son of his gardener.
- James developed a mild fever and recovered.
- Weeks later, Jenner exposed him to smallpox material. James didn’t get sick.
Such an experiment on a child would be considered unethical today, but it changed medicine.
Before Jenner
People in China, India, Africa and the Ottoman Empire had long practiced variolation, deliberately infecting people with small amounts of smallpox to cause a milder illness. Lady Mary Wortley Montagu introduced it to Britain in the 1720s after seeing it in Istanbul. It worked, but it was riskier than Jenner’s cowpox method.
From vaccine to eradication
| Year | Milestone |
|---|---|
| 1798 | Jenner publishes his findings |
| 1800s | Vaccination spreads worldwide |
| 1967 | The WHO launches an intensified global eradication campaign |
| 1977 | The last natural case is recorded in Somalia |
| 1980 | The WHO declares smallpox eradicated |
Smallpox remains the only human disease ever eradicated. Read more about the World Health Organization.
Jenner’s legacy
Jenner is often called the “father of immunology.” Louis Pasteur later extended the word “vaccine” to all such treatments in his honor. For another medical breakthrough, see who discovered penicillin. The immune system’s defenders are explained in what white blood cells do.
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