Travelers' Diarrhea: What You Need to Know
An Interview with CDC Travel Health Expert Phyllis Kozarsky
How can a change in diet trigger travelers' diarrhea?
It's due to eating different kinds of foods, such as much more spicy food or more fat than in our normal diets. That is not something we typically pay as much attention to avoiding when we travel, but we have to be wary of these things. Not every change in our bowel habits is due to infection. Infection is the most important cause of travelers' diarrhea and most is caused by bacteria.
Who is most likely to get travelers' diarrhea?
Some people are more susceptible than others, it's not clear why that is. You can be with a group and all consume the same thing, and some get sick while others do not.
There are a host factors involved. Stomach acid is our first defense mechanism against organisms that we ingest. Therefore, those on antacids, or who just have low stomach acid, often get travelers' diarrhea more easily. People who have underlying diseases of the gut, such as Crohn’s disease or AIDS, may be more susceptible to certain types of organisms causing travelers’ diarrhea.
What kinds of infection cause travelers' diarrhea?
For the most part, we're talking about bacterial infections. Almost 90% of travelers' diarrhea cases are caused by bacteria. The enterotoxigenic E. coli [ETEC, strains of common bacteria that produce a toxin affecting the gut] are most important cause. And then there are others such as salmonella, shigella, campylobacter, vibrio, and others that are less common.
Travelers' diarrhea may also be caused by viruses, such as norovirus, which is in the news a lot because of how quickly it can spread through a cruise ship.
Parasitic travelers' diarrhea is yet another kind. Giardia intestinalis is the most common of these, but there is a large number of parasites that can cause diarrhea. These are less frequent.
Aside from the obvious, how do you know you're coming down with travelers' diarrhea?
Sometimes it starts with fever and chills. You may get cramps, and then, of course very urgent loose stools in various amounts. Sometimes there is vomiting or bloody diarrhea. With norovirus, onset can be sudden, and vomiting is a much more prominent feature.
For bacterial and viral travelers' diarrhea, the incubation period is typically six to 48 hours after infection.
For protozoan travelers' diarrhea, there is usually more of a gradual onset with a few loose stools per day and increased gas and nausea. The incubation period can be one to two weeks.
What is the main treatment for travelers' diarrhea?
Hydration is the primary treatment. Often people with a bout of travelers' diarrhea feel so weak. A good deal of it is due to dehydration. It's not OK just to take a few sips of cola. You need to make the effort to drink a lot of fluid, because often you've lost a lot more than you think. In a lot of cases, just clean water is OK. Better, if you are very dehydrated, is a rehydration solution. Rehydration packets are a great thing to have, especially if you are going to remote areas or places off the usual tourist paths.