Topic Overview

What is traveller's diarrhea?

Traveller's diarrhea is a common medical problem for people travelling from developed, industrialized countries to developing areas of the world. Traveller's diarrhea is sometimes called by its more colourful names: Montezuma's revenge, Delhi belly, and Turkey trots.

High-risk areas for traveller's diarrhea include developing countries in Africa, Asia, the Middle East, and Latin America. Low-risk areas include the developed countries of North America, Central Europe, Australia, and Japan.

What causes traveller's diarrhea?

Traveller's diarrhea is usually caused by a bacterial infection. Bacteria such as Escherichia coli (E. coli), Campylobacter, Shigella, or Salmonella are the most common causes. These bacteria are in water contaminated by human or animal stools. Drinking water, water used to wash food, or irrigation water may be affected. When the traveller drinks this water or eats contaminated food, he or she is likely to get diarrhea.

Common sources of bacteria that cause diarrhea are undercooked or raw foods, contaminated food, or contaminated water (including ice cubes).

What are the symptoms of traveller's diarrhea?

Traveller's diarrhea can be mild to severe. Most people who develop traveller's diarrhea experience symptoms within the first two weeks, and often within 2 to 3 days, of arriving in a developing area. Symptoms include:

• Diarrhea.
• Abdominal cramps.
• Mild to severe dehydration.
• General lack of energy, nausea, and vomiting.
• Fever, vomiting, and stools with blood or mucus. These symptoms mean you have serious diarrhea, which is more likely to lead to problems with dehydration. Dehydration may alter the effect of any medicines being taken, such as oral contraceptives or antimalarials.

How is traveller's diarrhea treated?

Treatment for traveller's diarrhea includes drinking fluids to avoid dehydration, taking non-prescription medicines, and in some cases, antibiotics and intravenous (IV) fluids.

• Let your stomach rest. Do not eat for several hours or until you are feeling better.
• Take frequent, small sips of bottled or boiled water or a rehydration drink and small bites of salty crackers.
• If possible, drink a solution made with World Health Organization (WHO) oral rehydration salts. Packets of the salts are available at stores and pharmacies in most developing countries. Add one packet to boiled or treated water, making sure to read the instructions regarding the proper amounts of salts and water. Drink the solution within 12 hours if kept at room temperature, or within 24 hours if refrigerated.
• Begin eating a simple diet of bland foods, such as crackers, rice, bread, potatoes, or bananas, which usually will help slow diarrhea. After your diarrhea is gone, you may eat a regular diet again.

Children 2 years old or younger are at high risk of dehydration from diarrhea. If your child has diarrhea:

• Give your child a solution of WHO rehydration salts in addition to his or her regular food as long as diarrhea continues. If your baby has trouble keeping the liquids down, try giving frequent sips by spoon.
• Continue breast-feeding normally. Bottle-fed babies should drink lactose-free or reduced-lactose formulas.
• Feed your child starches, cereals, yogurt, fruits, and vegetables.
• Seek medical help immediately if you or your child has bloody diarrhea, fever, or persistent vomiting, and give rehydration fluids in the meantime.

Non-prescription medicines

Non-prescription medicines may help treat diarrhea. Use non-prescription antidiarrheal medicine if you do not have other signs of illness, such as fever, abdominal cramping or discomfort, or bloody stools. If you have fever, bloody stools, or vomiting, antibiotics may be needed.

Bismuth subsalicylate, or BSS (such as Pepto-Bismol), has been shown to be effective in preventing and treating traveller's diarrhea. Bismuth subsalicylates may reduce the effectiveness of medicines taken to prevent malaria, should not be used for more than 3 weeks, and should not be taken by those who can't take ASA. They may cause you to have a black tongue or black stools. The black colour is usually not serious. Brushing your teeth and tongue after taking a BSS may keep your tongue from turning black. If your child or teen gets chickenpox or flu, do not treat the symptoms with over-the-counter medicines that contain bismuth subsalicylate or ASA (such as Pepto-Bismol). If your child has taken this kind of medicine and he or she has changes in behaviour with nausea and vomiting, call your doctor. These symptoms could be an early sign of Reye syndrome, a rare but serious illness.

Non-prescription medicines to slow diarrhea, such as loperamide (for example, Imodium), may be used to treat diarrhea but should not be used to prevent traveller's diarrhea because they can cause constipation.

If you have a high-risk medical condition such as diabetes or cancer, you take prescription medicines that cause diarrhea, or you are travelling with a child 11 years old or younger, seek advice from your health professional to determine what medicines you may want to take on your trip. Be aware that dehydration caused by diarrhea may alter the effectiveness of any medicines you are taking for other medical conditions.

Can I prevent traveller's diarrhea?

The best way to prevent traveller's diarrhea is to avoid food or water that may be contaminated. A good rule of thumb for food safety is, "If it's not boiled, well-cooked, or peeled, don't eat it." Raw seafood and milk products usually are high-risk foods for bacterial contamination. Dry foods, such as breads, or fruits that you can peel are safe to eat.

Avoid drinking local water where you are travelling. Beverages that are usually safe to drink include:

• Tea and coffee if made with boiled water.
• Carbonated bottled water or soda pop.
• Bottled beer and wine.

Water also can be filtered or treated with iodine to make it safe to drink.

Also, be aware that contaminated water may be used to wash fruits and vegetables, clean utensils and plates, and make ice cubes. Brushing your teeth with untreated water also may increase your risk of infection.

Avoid eating food from street vendors where flies can transmit bacteria and poor hygiene practices are more likely to contaminate foods. If you purchase food at an outdoor market, make sure you boil it, cook it thoroughly, or peel it before you eat it.

Good handwashing is important in preventing the spread of infectious diseases. Washing with treated water or using alcohol wipes or antibacterial gels to disinfect your hands are good ways to reduce your risk of getting an infectious disease.

Talk with your doctor about antibiotics you can carry with you on your trip and instructions on when to use them just in case you should develop diarrhea.

Other information sources

Health Canada's Travel Medicine Program (TMP) offers information on international disease outbreaks and treatment and prevention guidelines. Local health departments can also access this information to help you determine what prevention measures—such as vaccines, antimalarial medicine, or supplies to treat water—are appropriate for the area of the world you are travelling to. The TMP also offers a Web site (www.travelhealth.gc.ca) with updated information for travellers.

Resources for medical care in a foreign country include embassies or consulates and major hotels. For English-speaking travellers, multinational corporations or credit card companies also may have referrals for local medical care in the foreign country.