Epidemiology is the study of disease in populations, to find the cause and a solution to epidemics. It is a unique science—epidemiology is different from the other branches of health science (such as medicine), because it focuses on how diseases occur in a group as a whole, not just specifically in one individual.
Because of the nature of epidemiology, the work of an epidemiologist doesn’t just affect one person, like a doctor or surgeon, but affects many people. Epidemiologists help millions of people everyday by using applied epidemiology to stop epidemics, preventing disease from spreading.
The information that epidemiologists gather though their work is also very important. For example, an epidemiological study that discovers a risk factor for a common disease can benefit thousands—or even millions—of people who now know how to avoid getting sick. Epidemiological information is also used by doctors to make clinical decisions, and by governments when they create policies.
Okasha, Mona. "“Epidemiology- Who Cares?”." Student BMJ (2001).
“An Introduction to Epidemiology.” Centers for Disease Control and Prevention.