Which events occured before 1900 AD?: (A) Establishment of seat of social medicine at Oxford, (B) Epidemiological work on cholera by John Snow, (C) Work on scurvy by James Lind, (D) Use of BCG vaccine
Answer is B. An english epidemiologist John Snow studied the epidemiology of cholera in London from 1848-1854 and established the role of polluted drinking water in spread of cholera. Ref : Park&;s textbook of preventive and social medicine; 23rd edition