On May 8, 1980. the 33rd World Health Assembly declared the world free of smallpox. This marked the first—and only—time a human disease had been eradicated globally.

From https://en.wikipedia.org/wiki/Eradication_of_infectious_dise...

Only 30 cases in 2022. Fingers crossed.

Relevant xkcd: https://xkcd.com/2448/

Too bad almost every large military has tested it as a biowarfare agent at some point.