What is traveler's diarrhea?

Traveler's diarrhea is a sudden intestinal infection that travelers often get when they are not used to microorganisms in the water supply or on the food in another country. It may be called gastroenteritis, Montezuma's Revenge, Turista, or the GI Trots.

About 20% to 50% of people from industrialized nations who travel to less developed countries get traveler's diarrhea. High-risk destinations include most of the developing countries of Latin America, Africa, the Middle East, and Asia.

How does it occur?

Traveler's diarrhea occurs when you eat food or drink beverages that are contaminated with organisms from human waste. Both cooked and uncooked foods may be contaminated. The cause of the infection can be a virus, a parasite, or bacteria. However, the bacterium Escherichia coli, which is normally found in the human intestine, is often the cause. When you are exposed to new varieties of E. coli bacteria, the bacteria produce toxins that interfere with your intestine's ability to absorb water, thus causing diarrhea.

Sometimes traveler's diarrhea is caused by the stress of traveling, jet lag, a different diet, or other factors.

What are the symptoms?

The following symptoms may develop:

• loose stools, as many as three to ten per day

• stomach cramps

• bloating and gas

• nausea and vomiting

• fever

• weakness

• dehydration (excessive loss of body fluids)

• headache (sometimes).

How is it diagnosed?

Your doctor will ask about the history of your problem, including the amount of diarrhea; whether you have with it blood, mucus, or bad-smelling gas; and if you have had vomiting, nausea, high fever, or weight loss. Your travel history is important: destination, whether you had well or spring water, exposure to local food and drink, and any medications you may have used.

If your diarrhea has persisted more than several days or is causing other symptoms, your doctor will want to examine you and order tests on bowel movement samples and possibly blood. A stool culture is done to attempt to grow bacteria and evaluation under the microscope identifies parasites. A complete blood count may indicate the severity of infection and may suggest a parasitic infection. It might show anemia if you have had blood loss because of bloody diarrhea.

How is it treated?

Even before the diarrhea is treated, you must try to prevent dehydration, which often follows diarrhea and can cause serious problems. Dehydration occurs when your body loses more fluids and salts (electrolytes: sodium and potassium) than it takes in.

To replace lost fluids and salts, you can use packets of oral rehydration salts, which are available at drug stores. You can make your own rehydration solution by mixing 1 liter of clean (or boiled) water, 2 tablespoons of sugar, 1/4 teaspoon salt, and 1/4 teaspoon of baking soda. Drinking other nonalcoholic drinks made with clean water will also help prevent dehydration, but they may not restore all the salts you need. Try to drink at least 8 ounces of fluid for each watery stool lost.

Drugs such as paregoric, codeine, diphenoxylate with atropine (Lomotil), loperamide (Imodium A-D), and bismuth subsalicylate (Pepto-Bismol) will not cure the diarrhea but may give temporary relief of your symptoms. Use over-the- counter medications in foreign countries with caution.

Traveler's diarrhea is usually a short-lived problem and will often stop without treatment. Nonprescription medications such as Kaopectate are of little help and can actually be worse than nothing, especially if the diarrhea is bloody. Do not treat your own symptoms if you have a high fever (102 degrees F, or 39 degrees C), blood in your stool, or symptoms that last for more than 48 hours. See a doctor as soon as possible. Do not give antidiarrheal medications to small children.

How long will the effects last?

The diarrhea usually stops on its own within 1 to 5 days. Rarely, it lasts 2 to 3 weeks.

How can I take care of myself?

Ask your doctor if you are concerned about visiting another country where diarrhea may be a concern. In addition, if you are traveling to a foreign country:

• Carry along some means to purify water, such as a filter or purifier, chlorine or iodine tablets, or pot and stove for boiling water.

• If you are buying a water filter or purifier, buy one that can filter out organisms as small as those that cause giardia, cholera, and amoebic diarrhea.

• Carry a liter of purified water and several packets of oral rehydration salts.

• Carry a few Imodium or Lomotil tablets with you for emergencies (e.g. to avoid toilet accidents on the way home).

• If you get diarrhea, avoid alcohol, coffee, and all milk products (milk, cheese, cream, pudding, etc.) most vegetables, fruits (citrus, tomatoes, etc.), red meats, and heavily seasoned foods. If you have no diarrhea after 6 to 12 hours, slowly begin to eat clear soup, salted crackers, dry toast or bread, and milk-free sherbet.

  Over the next few hours to 1 to 2 days, slowly add bananas, applesauce, rice, baked potato, and low-fat chicken soup with rice or noodles, and any plain noodles or pasta to your diet. After about 3 days your stools will begin to have shape an you may resume your normal diet, cautiously adding milk products and high fiber foods.

How can I prevent traveler's diarrhea?

Follow these guidelines:

• Do not drink untreated water, including ice cubes in drinks.

• Avoid food and beverages from street vendors.

• Eat only foods that are cooked and still hot, or fruits and vegetables that you peel yourself.

• Do not eat raw or partially cooked fish or shellfish, including such dishes as ceviche. Fully cooked fish and shellfish are safe.

• Brushing your teeth with untreated water is usually safe (most toothpastes contain antibacterial substances), but do not swallow the water.

• Carbonated soft drinks and water, bottled water, wine, and beer are usually safe as long as you do not add ice.

• Avoid uncooked dairy products.

You may discuss with your doctor the pros and cons of taking antibiotics with you. Most current recommendations are to start antibiotics only if you develop symptoms of diarrhea. Doxycylcine and Bactrim or Septra have been used in the past, but more organisms are becoming resistant. The present drugs of choice are ciprofloxacin or norloxacin. Usual prescription is for 3 days only. These medicines can cause side effects, including sun sensitivity.