Epidemiology is the science addressing disease patterns at the population level. This field of study is the chief tool of public health analysis, and provides insights for disease propagation within a population, the risk factors for disease and determination of optimal treatment approaches to clinical practice for disease treatment. In the study of communicable diseases, epidemiologists rely on certain related disciplines such as chemistry, environmental science, biology, biostatistics, geographic information science and social science.

History of epidemiology

Hippocrates is usually considered the father of epidemiology, since he was the earliest physician to have analyzed the relationship between disease occurrence and environmental influences. Using the Greek language he coined the original terms for endemic (a disease occurring in a given location) and epidemic (a disease that is widespread).

Alternative definitions

IUPAC definition 

International Union of Pure and Applied Chemistry (Chemistry and Human Health Division) Glossary of Terms Used in Toxicology (Second Edition) defines epidemiology as the:

"Study of the distribution and determinants of health-related states or events in specified populations and the application of this study to control of health problems".

USDA definition 

The U.S. Department of Agriculture's Food Safety and Inspection Service (FSIS) defines epidemiology as:

"The study of the distribution of disease, or other health-related conditions and events in human or animal populations, in order to identify health problems and possible causes".

EPA definition 

The U.S. Environmental Protection Agency (EPA) defines epidemiology as:

"The study of the distribution of disease, or other health-related states and events in human populations, as related to age, sex, occupation, ethnicity, and economic status in order to identify and alleviate health problems and promote better health".




(2007). Epidemiology. Retrieved from http://www.eoearth.org/view/article/51cbedc07896bb431f693a67


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