What is Epidemiology?

Briefly, Epidemiology is a scientific study of the occurrence and spread of diseases within and between populations. Epidemiology is considered the methodological study of disease and population health.

One speaks of microbial epidemiology in the occurrence and spread of pathogens. The link between smoking and lung cancer, discovered by Englishman Sir Richard Doll, is one of the most important discoveries by epidemiology.