Edward Jenner (1749 - 1823)

He was born in Gloucestershire, England, and trained in London to become a doctor. He settled into Gloucestershire as a country doctor.

For many years a dreadful disease called smallpox had been as widespread as cancer is now, but it usually attacked young children. Many people that caught it, died from the disease, and those that survived were left with terrible scars (pockmarks) on their faces. In fact, it was thought that one person in every five, in London, had pockmarked faces.
The disease had been widespread in other countries such as Turkey, India and China for many centuries, and people there had many ideas about how not to catch it. They believed that if you caught a very mild form of the disease, you would escape a serious attack, and in India, babies were wrapped in clothes from an infected person, for this to happen.

Jenner had once heard a milkmaid say, "I can't catch that disease. I've had the cowpox". Although no one knew about viruses at that time, cowpox was a similar disease to smallpox, and although humans could catch it, it was much milder than smallpox.
When another milkmaid came to him with cowpox, Jenner extracted some of the poisonous matter from the sores on her hand before sending her home.

He then 'infected' a neighbour's son with the cowpox, and a few weeks later, with poison from a smallpox victim. The boy did not catch the disease. Jenner repeated his experiment with 23 more people before he felt certain enough to tell everyone about it. Even then few people believed him, but with nothing else to try against the disease, some doctors in Oxford followed his example. They injected cowpox into 326 people and infected 173 of them with smallpox some weeks later. No one caught the disease!

After this, Jenner became the most talked about man in the world. He called the procedure 'vaccination' from the Latin word vacca, meaning 'cow'. Today we still use the principle that Jenner used, although the viruses in the vaccines are killed first. Nearly everyone in the world is vaccinated nowadays and no one in the world has had smallpox for many years.

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