This is an infection of the digestive system. It causes loose, watery poop. Traveler's diarrhea gets its name because it often strikes after visits to places with poor public hygiene.
What causes it? Usually it comes from contaminated food or water. Eating or drinking something that wasn't prepared, handled or stored properly lets harmful bacteria get into your body. Or, you can be infected by a virus or parasite. So when you travel, be careful about what you eat and drink. Avoid anything that could be contaminated. Use only water that has been boiled or sanitized. And always wash your hands after going to the bathroom.
Along with loose, watery poop, symptoms may include nausea, vomiting, and belly pain or cramps. You may have trouble getting to a restroom in time. You may have blood in your poop. And, you may feel tired and bloated.
Traveler's diarrhea usually doesn't last for more than a few days. While you have it, drink plenty of fluids to stay hydrated. If your symptoms are severe, or if your condition isn't getting better, see your doctor. You may need medication.