The Grammarphobia Blog

A “pandemic” epidemic!

Q: When did “pandemic” replace “epidemic” to mean everybody gets the same sickness everywhere? Also, why did the usage change?

A: A disease is said to be “epidemic” when it becomes widespread within a specific community or population at a particular time and later subsides. It’s said to be “endemic” when it exists all the time in (or is native to) a given community or population. It’s said to be “pandemic” when it spreads throughout a whole country or continent or the world.

An easier way to remember: the prefix “epi” means “upon” or “close to”; “en” means “in” or “within”; “pan” means “all.” I do think that newscasters and writers sometimes use the word “pandemic” because they think it’s scarier than “epidemic,” which I suppose it is!