02/19/2012 10:26 am ET

13 Things You Should Know About The Stomach Flu

By Anne Harding

Ugh, what could be worse than a stomach bug? The vomiting, diarrhea, stomach cramps and more.

Despite the fact that it's so common -- there are at least 20 million stomach-flu cases in the U.S each year -- many people don't know much about it. For one, it's not really the flu!

Here are 13 things you need to know about viral gastroenteritis (its true medical name), starting with the fact that it's caused by viruses that attack the stomach and intestines.

13 Things You Should Know About Stomach Flu