Word parts
What it means
The science of health and disease in populations. Epidemiologists track how many people have a disease (prevalence), how many new cases appear in a period of time (incidence), where and when it happens and what raises the risk. Public health uses this to find outbreaks, trace how an infection spreads and plan prevention.
Related terms
community health
The health of the people who live in a certain area or share something in common, and the work done to improve it.