In 1796, English doctor Edward Jenner tried a very risky experiment.
He gave James Phipps, age 8, a mild disease called cowpox. About six weeks later, he infected James with a deadly disease called smallpox. Jenner thought having cowpox would make a person safe from smallpox. He was right! Within five years, people everywhere were using his smallpox vaccination. Suddenly, a disease that had killed millions began to go away. By 1980, smallpox was extinct.
Today, Americans on average live almost twice as long as they did in Jenner’s time. That’s mostly because of advances in medicine and science. They weren’t caused by the Industrial Revolution. But they happened around the same time.