Until Now
MedicineScience

Germ theory

Disease is caused by organisms, and medicine finally becomes effective.

When
Duration
28 years
Known to
± 1 year
Era
Industrial, Holocene

Snow traces a London cholera outbreak to a single water pump in 1854 before anyone knows what causes it. Pasteur disproves spontaneous generation and links microbes to fermentation and disease; Lister applies it to surgery with carbolic acid from 1867, cutting mortality dramatically; Koch identifies the anthrax, tuberculosis and cholera bacilli and sets out criteria for proving causation. For the first time doctors reliably do more good than harm.

Just before

Just after