Introduction
This topic defines epidemiology, lists its tasks and methods (observational and experimental studies), and describes the natural history of disease with the levels of prevention that match it.
Epidemiology
- From Greek: epi = upon, demos = people, logos = science.
- It studies the distribution and determinants of disease in human populations and applies this study to the control of health problems (in the interest of public health).
- It is the medical science interested in what causes disease and how disease spreads among people.
- Main aim: to find, study, establish and assess a causal relationship between an exposure to a risk factor (the presumed cause) and an outcome (its potential effect).
- It is used in evidence-based clinical medicine to identify risk factors (RFs) for disease and to decide optimal treatment approaches in clinical practice.
- It studies all diseases, not only infectious ones. General epidemiology studies human health; infectious disease epidemiology is a part of it. Infectious disease science studies animals and the life cycle of biological agents.