How Dr John Snow applied the two uses of epidemiology to deal with cholera outbreak in London?

John Snow applied the two uses of epidemiology, descriptive epidemiology and analytic epidemiology, to deal with the cholera outbreak in London in 1854.

Descriptive epidemiology involves observing and describing the patterns of disease occurrence. Snow used descriptive epidemiology to map the cases of cholera in London and identify the areas that were most affected. This allowed him to identify the source of the outbreak, which was a contaminated water pump on Broad Street.

Analytic epidemiology involves testing hypotheses about the causes of disease. Snow used analytic epidemiology to test the hypothesis that the cholera outbreak was caused by contaminated water. He did this by comparing the rates of cholera in areas that were served by the contaminated water pump to the rates of cholera in areas that were not. He found that the rates of cholera were much higher in the areas that were served by the contaminated water pump, which supported his hypothesis.

Snow's use of epidemiology was instrumental in stopping the cholera outbreak in London. By identifying the source of the outbreak and testing the hypothesis that the outbreak was caused by contaminated water, Snow was able to develop and implement effective control measures. These measures included removing the handle from the contaminated water pump and boiling water before drinking it. As a result of these measures, the cholera outbreak was quickly brought under control.

Snow's work on the cholera outbreak in London is considered a landmark in the field of epidemiology. It demonstrated the power of epidemiology to identify the causes of disease and develop effective control measures. Snow's work also helped to establish epidemiology as a scientific discipline.