When Max von Pettenkofer shot himself to death in 1901, he left behind a storied career as a hygienist and bitter opponent of Robert Koch, the German physician and microbiologist who discovered the cholera bacillus, Vibrio cholerae. Von Pettenkofer, the founder of the Institute of Hygiene in Munich, disputed Koch’s germ theory of disease, which held that a germ is both necessary and sufficient to cause illness. Von Pettenkofer asserted that germs could only cause disease in the presence of a “local” or environmental factor.
The battle between the two men exploded into a bitter divide over the question of the infectivity of cholera. Koch and his fellow contagionists maintained that the bacterium was spread through the water. Von Pettenkofer and his localists believed that cholera was inhaled as a miasma, which arose from earth contaminated by sewage. Anxious to prove his theory that germs alone don’t account for