|1.||(esp of a disease) attacking or affecting many persons simultaneously in a community or area|
|2.||a widespread occurrence of a disease: an influenza epidemic|
|3.||a rapid development, spread, or growth of something, esp something unpleasant: an epidemic of strikes|
|[C17: from French épidémique, via Late Latin from Greek epidēmia literally: among the people, from |
epidemic ep·i·dem·ic (ěp'ĭ-děm'ĭk) or ep·i·dem·i·cal (-ĭ-kəl)
Spreading rapidly and extensively by infection and affecting many individuals in an area or a population at the same time, as of a disease or illness. n.
An outbreak or unusually high occurrence of a disease or illness in a population or area.
an occurrence of disease that is temporarily of high prevalence. An epidemic occurring over a wide geographical area (e.g., worldwide) is called a pandemic. The rise and decline in epidemic prevalence of an infectious disease is a probability phenomenon dependent upon transfer of an effective dose of the infectious agent from an infected individual to a susceptible one. After an epidemic has subsided, the affected host population contains a sufficiently small proportion of susceptible individuals that reintroduction of the infection will not result in a new epidemic. Since the parasite population cannot reproduce itself in such a host population, the host population as a whole is immune to the epidemic disease, a phenomenon termed herd immunity.
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