John Snow (Public Health Pioneer)

John Snow was a pioneering public health scientist who, in the mid-1800s, helped identify how cholera spreads. During a deadly outbreak in London, he mapped cases and traced them to a contaminated water pump on Broad Street. His work demonstrated that contaminated water, not miasma or bad air, was the source of the disease. By removing the pump handle, he helped stop the outbreak. Snow's approach laid the foundation for modern epidemiology, emphasizing data collection, investigation, and scientific analysis to control disease and improve public health.