Public Health is a branch of medicine that is concerned with prevention and control of disease and the promotion of physical and mental health and wellness of populations on international, national, state, county and community levels.
Community Health concerns itself with plans to improve the health and prevent disease and improve accessibility of health services for a whole community.
Epidemiology is a narrower focus on the study of the interrelationship between the agent and host and environment. The study of disease outbreaks affecting human populations.
Definitions of these terms were written from the descriptions in the MeSH database in the PubMed Database.