What is an "epidemic"?

An epidemic is an outbreak of a disease that spreads quickly and affects a large number of people within a community, region, or population at the same time, in contrast to a pandemic, which is a global outbreak of a disease. An epidemic often involves illnesses that were previously controlled or uncommon in the area. The spread can happen through person-to-person contact, contaminated food or water, or other methods. Public health measures, such as vaccination, quarantine, and hygiene practices, are typically used to control and prevent further spread of the disease.