Can traveler's diarrhea be contagious?

Not usually. Traveler's diarrhea occurs when you accidentally eat or drink food contaminated with germs. To prevent it eat cooked food served hot, drink bottled water and avoid fresh produce, buffet meals, dipping sauces, and ice in your drinks. Of course you will want to wash your hands before you eat and after toileting. If two people on the same trip get sick, usually they have eaten the same food.
YES! This type of diarrhea can be caused by viruses or bacteria. These can be transmitted person to person through poor hand washing after wiping or other exposure to an infected person's stool. They are not passed through saliva, coughing, sneezing or kissing.