A new four-part series in which Jolyon Jenkins finds out how epidemiologists go about their job of linking illness, disability and death to particular behaviours. 1: The Broad Street Pump In 1854
, during a cholera outbreak in London, a local doctor, John Snow , realised the cases clustered around Broad Street, where there was a water pump. Hypothesisingthat the pump might be the source of the infection, he put it out of use. The epidemic declined markedly, apparently providing evidence that the disease was water-borne. Using Snow's journals and interviews with modern epidemiologists and medical historians, the story of the Broad Street pump is a gentle and accessible introduction to epidemiology. Producer Paul Arnold