NURSING ANM AND GNM

Detailed explanation-1: -John Snow conducted pioneering investigations on cholera epidemics in England and particularly in London in 1854 in which he demonstrated that contaminated water was the key source of the epidemics.

Detailed explanation-2: -Snow was able to prove that the cholera was not a problem in Soho except among people who were in the habit of drinking water from the Broad Street pump. He also studied samples of water from the pump and found white flecks floating in it, which he believed were the source of contamination.

Detailed explanation-3: -"For his persistent efforts to determine how cholera was spread and for the statistical mapping methods he initiated, John Snow is widely considered to be the father of [modern] epidemiology."