John Snow (epidemiologist and mapmaker)

John Snow was a 19th-century British physician and pioneer in the field of epidemiology, which studies how diseases spread. He is best known for his investigation of a cholera outbreak in London in 1854. By mapping the locations of cholera cases, he identified a contaminated water pump as the source of the outbreak, demonstrating the link between contaminated water and disease. His work laid the foundation for modern public health practices and disease mapping, emphasizing the importance of clean drinking water and sanitation in controlling epidemics. Snow’s methods were innovative for their time and significantly advanced the understanding of disease transmission.