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In 1854 in London, England, A Cholera outbreak occurred near Broad Street. John Snow, a physician, hypothesized that it was not contaminated air, known as the "miasma theory," but was rather contaminated water that was spreading the disease.Snow mapped the Cholera deaths and persuaded authorities to stop the residents from using the pump by removing its handle.Because of his actions, John Snow is known as the father of modern epidemiology.
