John Snow (Physician)

John Snow was a 19th-century British physician known as one of the founding figures of modern epidemiology. He is best known for his work during a cholera outbreak in London in 1854, where he mapped cases of the disease and traced its source to a contaminated water pump on Broad Street. His pioneering use of data and mapping to understand disease spread laid the groundwork for public health measures and the importance of clean water. Snow’s efforts significantly advanced our understanding of how diseases can be transmitted and the importance of sanitation.