Overview

John Snow (March 15, 1813 - June 16, 1858) was a British physician and a leader in the adoption of anaesthesia and medical hygiene. He is considered to be one of the fathers of epidemiology, because of his work in tracing the source of a Cholera outbreak in Soho, England, in 1854.

John Snow was one of the first physicians to study and calculate dosages for the use of ether and chloroform as surgical anaesthetics, allowing patients to undergo surgical and other procedures without the distress and pain they would otherwise experience.

Snow was a sceptic of the then dominant miasma theory that stated that diseases such as cholera or the Black Death were caused by pollution or a noxious form of "bad air". The germ theory was not to be created until 1861, so he was unaware of the mechanism by which the disease was transmitted, but evidence led him to believe that it was not due to breathing foul air. He first publicized his theory in an essay On the Mode of Communication of Cholera in 1849. In 1855 a second edition was published, with a much more elaborate investigation of the effect of the water-supply in the Soho, London epidemic of 1854.

To the right is the original map by Dr. John Snow showing the clusters of cholera cases in the London epidemic of 1854.

To the left, the pump in Soho, London and John Snow pub in background.

References

John Snow - wikipedia