Why Did Milkmaids Not Get Smallpox?

And the milkmaids themselves were getting similar bumps on their hands and were coincidentally not getting smallpox. Milkmaids were thought to be immune to smallpox and, before long, it became known that if you too wanted to be immune, all you had to do was get exposed to “cowpox

How were milkmaids immune to smallpox?

As history tells it, young Edward Jenner heard a milkmaid brag that having cowpox made her immune to smallpox. And years later, as a doctor, he drew matter from a cowpox pustule on the arm of a milkmaid to vaccinate a young test subject (depicted in the drawing above).

Why were milkmaids smallpox resistant?

Jenner, a physician and scientist, noticed that milkmaids generally didn't develop smallpox, a disfiguring and sometimes deadly disease. He guessed it was because they sometimes caught cowpox, a related disease that only caused mild illness in people.