Ueber Cholera mit Berücksichtigung der jüngsten Choleraepidemie in Hamburg
1892
Pettenkofer's 1892 paper written after the Hamburg cholera epidemic. To test Koch's claim that the comma bacillus alone causes cholera, he drank a live culture and recorded his symptoms for a week, and his colleague Emmerich did the same with a larger dose. Both got diarrhea and recovered, and Pettenkofer argued that cholera also needs a local factor in soil and groundwater.