Surely, you’re familiar with this one. Diarrhea can be caused by many things, including a virus, a bacteria, or even a parasite. Either way, it will usually be over within a few days. Preventing diarrhea is hard because it is so common. You can, however, reduce your risk with good hand washing habits, cleaning your counter tops frequently and washing food thoroughly. Read below for a more in depth outline on the causes and symptoms of diarrhea.