Definitions: Outbreak, Epidemic, Pandemic

[Crabtownboy]

Ebola is very much in the news and as the response is not up to the level where it is being contained will continue to spread, possibly becoming worldwide, in other words to become a pandemic. I thought it a good idea to give a few definitions:

An outbreak is a small surge in morbidity and mortality in a locality. So, we might talk of an outbreak of influenza in New Haven.

An epidemic is a much bigger surge, over a larger area.

And a pandemic is when an epidemic goes transnational; becomes an international phenomenon, affecting whole continents, or occasionally going global.

http://oyc.yale.edu/transcript/596/hist-234