So gastroenteritis is just a fancy word for everybody’s friend, the stomach flu. Well, that’s not entirely accurate, because while flu can cause gastroenteritis, all sorts of other viruses, bacteria, parasites, or other inflammatory processes can cause it as well. While we don’t have to think about what this means, typically the infectious variety is spread by what’s called fecal oral transmission, which is as gross as it sounds, but it means that someone’s dirty hand touched something that got into your mouth. Not surprisingly, a lot of transmission is inside households or crowded places like cruise ships. It’s defined by having two or more stools, more than normal. So this is important when you’re talking about kids who might be pooping a lot more in a day, and it has to be within two weeks or it’s no longer called acute gastroenteritis. Many folks will also have nausea and vomiting as well. Usually that tends to precede the part where you get diarrhea.