Modern vaccination began in England during the late 1700s. At the time, one of the most feared diseases was smallpox. And as the world’s population grew and travel increased, smallpox deaths grew. It’s estimated that in the twentieth century alone, about 300 million people died worldwide until vaccination wiped the disease out entirely.
The vaccine is thanks to the work of an English doctor, Edward Jenner, who noticed that during outbreaks of smallpox people who worked with cows were not infected. He believed this was because they may have caught cowpox, a much milder disease that affected primarily cows, which protected them—or made them immune—to smallpox. After 20 years of testing and research, Dr. Jenner’s breakthrough came in 1796 and by the early 1800s, governments began encouraging people to use his smallpox vaccine.
By the 1850s, Great Britain made smallpox vaccinations mandatory for infants and vaccinations steadily grew around the world. Come the 1960s, the World Health Organization stepped up efforts at vaccinating more people and in 1977 the last case of smallpox occurred. The world was certified free of smallpox in 1980 thanks to Dr. Jenner’s pioneering work to make people immune through vaccines.