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Video on John Snow and the Cholera Epidemic in 1854

John Snow was a doctor in London who famously identified the source of a cholera outbreak in 1954. At the time, it was assumed that cholera was airborne. However, Snow did not accept this 'miasma' (bad air) theory, arguing that in fact entered the body through the mouth. He published his ideas in an essay 'On the Mode of Communication of Cholera' in 1849. In 1854 Snow was able to prove his theory when a cholera outbreak occurred in Soho. After careful investigation, including plotting cases of cholera on a map of the area, he was identified a water pump in Broad (now Broadwick) Street as the source of the disease. He had the handle of the pump removed, and cases of cholera immediately began to decrease