Traveler's Diarrhea

Travel to developing countries increases a person's risk of developing traveler's diarrhea.

What is the medical definition of traveler's diarrhea?

Diarrhea occurs in a significant number of people who travel to foreign countries. Travelers to developing countries of the world become ill from eating or drinking food or water contaminated by infected human bowel waste.

Traveler's diarrhea can be defined as three or more unformed stools in a 24-hour period.

Who is at risk for traveler's diarrhea?

• People traveling from industrialized countries to developing countries.
• Traveler's diarrhea is more common in young adults.
• A large percentage of travelers to the high-risk areas will develop diarrhea.

High-risk areas

• Mexico
• Latin America
• Africa
• Middle East
• Asia

Moderate-risk areas

• Caribbean islands
• Southern Europe
• Israel

Low-risk areas

• United States
• Canada
• Northern Europe
• New Zealand
• Australia

A person can become infected by eating or drinking food or water that has come in contact with feces. Food and water become contaminated when they are handled by people with fecal content on their hands - not in direct contact with feces. Restaurants are common sites for exposure to this type of food poisoning. Food from street vendors is even more risky. Eating in a private home is the safest food source.

High-risk food and drink

Certain items are considered high risk for transmission and include the following:

• Raw or undercooked meats
• Raw leafy vegetables
• Seafood
• Unpeeled fruits
• Unpasteurized dairy products
• Tap water (A common mistake travelers make is to avoid tap water but to place ice cubes in a beverage. Contaminated ice is still able to transmit disease. Do not use ice cubes.)

Safe products to eat and drink

• Bottled carbonated beverages
• Hot coffee or tea
• Water boiled or treated appropriately with chlorine

Specific bacterial causes of traveler's diarrhea

A majority of traveler's diarrhea is caused by bacteria. The remaining cases are caused by viruses and protozoa. The most common organism causing traveler's diarrhea is Escherichia coli accounting for most of cases in some regions.

Other bacterial causes of traveler's diarrhea

• Subtypes of E coli
• Shigella s species
• Salmonella species
• Campylobacter jejuni
• Vibrio species

Protozoa causing traveler's diarrhea

• Giardia duodenalis/lamblia/intestinalis, known as giardiasis
• Entamoeba histolytica
• Cryptosporidium parvum

Viral causes of traveler's diarrhea

• Norwalk virus (norovirus)
• Rotavirus virus
• Enteroviruses

Traveler's diarrhea usually does not begin immediately on arrival in a foreign country but starts two to three days into the stay. Diarrhea can also occur after a person returns home from a trip.

Common signs and symptoms of traveler's diarrhea (not all symptoms will be present at one time)

• Loose or watery stools
• Abdominal cramping
• Bloating
• Nausea
• Urgency to have a bowel movement
• Fever
• Vomiting
• Headache
• Painful bowel movements
• Bloody stools

When to call the doctor

• If diarrhea lasts longer than three days
• If blood, mucus, or worms are seen in the stool
• If the person has pain in the abdomen or rectum
• If the person has a temperature greater than 102 F (38.8 C)
• If a severe headache develops
• If the person has signs of water loss including dry mouth, excessive thirst, little or no urination, or feels lightheaded
• If the person's immune system is weakened by another condition such as HIV or cancer
• If the symptoms do not improve when the individual drinks fluids or uses nonprescription medications for diarrhea
• Vomiting prevents fluid intake

When to go to the hospital

• Continuing bloody diarrhea
• Severe weakness
• Passing out (fainting)
• Dehydration

Diagnosis of traveler's diarrhea is made solely on the signs and symptoms. Laboratory testing is not necessary in most instances. If signs and symptoms last longer than a week or bloody diarrhea occurs, the doctor may order stool cultures for microscopic examination for parasites.

Yes, no matter what the pathogenic cause (bacterial, viral or parasitic, see above) traveler's diarrhea is contagious. The vast majority of individuals obtain the pathogens by orally ingesting them. Common routs that lead to oral ingestion are by eating food or drinking water contaminated with the pathogens. Pathogens also survive sometimes for days on surfaces such as handrails, doorknobs, computer keys, children's toys, and many other similar items. The pathogens are then transferred to the mouth by a person simply touching their face on or near an oral mucosal area (lips, tongue, gums, teeth, for example).

For mild cases, the doctor may recommend the nonprescription medications bismuth subsalicylate and loperamide (see the previous precaution).

The use of antibiotics can reduce the duration of illness from days to hours. For moderate to severe diarrhea, the doctor may prescribe one of these antibiotics:

• trimethoprim-sulfamethoxazole (Bactrim DS)
• ciprofloxacin (Cipro)
• norfloxacin (Noroxin)
• ofloxacin (Floxin)
• doxycycline (Vibramycin)

Drink 2-3 quarts of fluid per day. In the first 24 hours the best fluids to drink are bottled fruit juices and beverages, caffeine-free soft drinks, hot tea, and broth; try to match the amount of fluid lost in the stools with the amount of fluid taken in orally.

During the next 24 hours, eat bland foods such as rice, soup, bread, crackers, eggs, and cereals. Advance to regular foods after two or three days.

With more severe cases, over-the-counter medications may help reduce symptoms and shorten the time they last.

• Antimotility agents, such as loperamide (Imodium), give the stools more consistency and provide some relief from symptoms, however, many health care practitioners use these agents for emergencies only (airplane travel) because the decreased motility may prolong the disease.
• Bismuth subsalicylate (Pepto-Bismol) is also moderately effective. Use according to package directions or upon the direction of a doctor.

Avoid these foods when traveling:

• Raw vegetables
• Raw fish, meat, and dairy products
• Raw leafy vegetables
• Unpeeled fruits
• Tap water
• Ice
• Any food from street vendors

These foods and drinks are generally safe to eat and drink.

• Well-cooked fish, meats, and vegetables served hot
• Carbonated beverages
• Boiled water (3-5 minutes)
  • If boiling water is not possible, other options include putting tincture of iodine drops in water (5 drops per quart of water), use of tetracycline iodine drops in water, or chlorine bleach to treat water (two drops per quart of water). These preparations can be obtained from camping and sporting goods stores. These methods are not as effective if water is cloudy or muddy.
• It is best to see your physician prior to foreign travel and bring the necessary medications with you to prevent any unnecessary trips to doctors or hospitals in foreign countries.
• The use of a single daily dose of an antibiotic is up to 90% effective in preventing traveler's diarrhea; however, preventive use of antibiotics is not routinely recommended except in special circumstances such as travelers with weakened immune systems, those with significant other medical illnesses, or for people traveling to very high-risk areas.

Although it can ruin a vacation, traveler's diarrhea rarely requires hospitalization and usually is not life-threatening unless severe dehydration develops.

• Untreated, diarrhea typically lasts three to five days.
• Twenty percent of people have symptoms severe enough to keep them in bed.
• In some people, the illness will last more than a week.
• Traveler's diarrhea is not life-threatening to an otherwise healthy person. In the very young, very old, and people with weakened immune systems, it can be dangerous.