Pettenkofer was a late 19th century medical researcher and public health advocate who developed the very first large-scale pure-water system in Munich, Germany. And even though that's probably very impressive, from now until the day you die, if you remember anything about Pettenkofer, it will be this: Max Josef von Pettenkofer drank a steaming cup of cholera bacteria that he cultured from a patient's diarrhea bombs.
Yeah, he got sick. But he didn't get sick enough to die, and Pettenkofer considered that proof of his theory that the cholera bacterium needed a victim who practiced poor sanitation. Of course, one could argue that without poor sanitation, the bacterium wouldn't be spread, outside of scientists who ingested it on purpose. Anyway, read about Pettenkofer and five other scientists at Cracked. Link