John Snow (cholera studies)

John Snow was a pioneering epidemiologist who studied a cholera outbreak in London in 1854. He traced cases to a contaminated water pump on Broad Street, demonstrating that cholera spread through contaminated water rather than miasma (bad air). By removing the pump handle, he effectively stopped the spread of the disease in that area. Snow’s work was fundamental in establishing the importance of sanitation and water supply in preventing infectious diseases, laying the groundwork for modern epidemiology and public health practices.