When people think of public health, they often think of the development of epidemiology and a famous public health story about John Snow in 1854. What he did was to map the cholera cases in London and then talk with the people to look for common links between their behaviors and the disease. ...Ever since John Snow removed the pump handle from the cholera infected well in London, heralding the start of population-based health care, the world has struggled with the realities of health promotion and disease prevention.