There’s nothing that plagues travellers more than diarrhea. Caused by ingesting bacteria, viruses, or protozoa, Travellers’ Diarrhea (TD) is one of the trickiest illnesses to avoid. Fortunately, most cases resolve after a few unpleasant days but in some, TD can lead to more serious health effects or conditions such as Postinfectious Irritable Bowel Syndrome (PI-IBS).
In today’s blog, we’re looking at some of the ways you can reduce your risk and what to do if you get sick during your trip.
What’s the risk?
TD can affect up to 70% of travellers. It is most commonly caused by bacteria (such as Escherichia coli, Campylobacter jejuni, Shigella spp., Salmonella spp., and others) transmitted via the fecal-oral route – when infected fecal particles are ingested through contaminated food or water, or by touching your mouth with dirty or improperly washed hands.
Acute gastrointestinal illnesses can occur anywhere in the world, but risk increases in areas where food handling and hygiene regulations are not always enforced and sanitation infrastructure are limited. It’s not always easy to discern the risk when travelling internationally; when we’re away from home, we may be less familiar with where our food came from, how it was prepared, and who handled it.
How can I reduce the risk of Travellers’ Diarrhea?
There are numerous products, medications, and practices that claim to reduce the risk of TD, but do they work? Below, we discuss common TD prevention methods and how effective they really are.
Food and water precautions
Food and water precautions (for example, ‘Boil it, cook it, peel it, or forget it!’) are often suggested as the main form of TD prevention, but studies have shown that following these precautions have little to no benefit.
Despite the lack of evidence, it can still be useful to follow some general rules when eating and drinking abroad to help you stay well. Opt for foods that are well-cooked, baked, or served hot. Where possible, avoid raw or undercooked meat and fish, and fruits and vegetables that are not washed with treated water. In destinations where the tap water is not safe, drink boiled or filtered water and use a reusable container to store your water. (Due to the negative environmental effects of plastic bottles, bottled water should only be used as a last resort. You can read about water disinfection methods here and responsible water use here). You should also stay away from restaurants and food vendors that appear to have poor hygiene standards (for example, watch out for dirty cutlery, unclean surfaces, and restaurants without patrons). Check out food and water safety for more tips.
Hand hygiene
One method that has been shown to be effective at reducing the risk of TD is washing your hands. Always wash your hands with soap and water, especially before eating, after leaving the bathroom, and touching public surfaces (handrails, doorknobs). Use hand sanitizer with at least 60% alcohol when water and soap are not available.
Over-the-counter supplements
You may have come across a number of over-the-counter products marketed for TD prevention. For example, supplements such as bovine colostrum and pre- and probiotics containing lactobacillus claim to provide protection against TD but there is insufficient evidence that these products are effective.
Bismuth subsalicylate
Products containing bismuth subsalicylate (e.g. Pepto-Bismol) can relieve heartburn, diarrhea, and indigestion. They come in liquid or tablet form and can reduce the risk of TD when used every day as a preventive measure. However, there are side effects including constipation, nausea, black tongue and stools, and ringing in the ears. Bismuth subsalicylate is not safe for pregnant women and children under 12.
Antibiotics
It is not advisable to prevent TD with antibiotics. There are a number of reasons for this:
- They only provide protection against bacterial strains of TD, not viral or protozoal infections.
- Overuse of antibiotics is a major contributor to the increase of antibiotic-resistant bacterial strains, a significant and growing global health problem.
- Antibiotics can cause upset stomach, rash, and in some cases, diarrhea – the exact problem you are trying to avoid. Antibiotics also interact with most drugs and can cause yeast infections in women.
Because of these risks antibiotics are not a reasonable method of Travellers’ Diarrhea prevention for the typical traveller.
In some instances, antibiotics may be prescribed by your doctor to prevent TD if you are at high risk of complications due to an underlying medical condition such as an immunosuppressive condition, low stomach acid (hypochlorhydria), or irritable bowel syndrome. Travellers may also be prescribed antibiotics if they are on short-term work assignments, such as high-level business trips or athletes competing in high-risk areas.
Using antibiotics for treatment of TD is discussed below.
Vaccines
Prophylactic vaccines, like Dukoral, are also heavily marketed to travellers as a form of TD prevention. Dukoral is an oral vaccine available in Canada and many other countries (not sold in the USA) for protection against Cholera. It is also marketed for protection against Travellers’ Diarrhea.
Dukoral has shown to be about 60% effective at preventing TD caused by Enterotoxigenic Escherichia coli (ETEC), which causes 25-50% of TD cases. It does not protect against other pathogens that cause TD. As a result, it is not recommended for travellers for the prevention of TD and should only be considered when travelling to areas with active Cholera outbreaks.
How can I manage Traveller’s Diarrhea if I become sick?
When there’s no guarantee you can avoid TD, the best thing to do is know how to manage it. Below we discuss strategies and when (or if) they should be used.
Based on the severity of symptoms, TD is typically categorized as mild, moderate, or severe. The following chart indicates the symptoms and recommended management strategies for each:
| Type | Symptoms | Management |
| Mild | Few unformed stools. Generally tolerable. Does not interfere with daily activities. |
Increase fluid intake. Anti-motility agents or bismuth subsalicylate may be used. Antibiotic is not recommended. |
| Moderate | Loose or liquid stools; cramps or nausea may also occur. Becomes distressing and interferes with daily activities. No blood in the stool. |
Increase fluid intake. Can use an anti-motility agent or bismuth subsalicylate. An antibiotic is not encouraged but may be used. |
| Severe | Loose or liquid stools that become debilitating. Cramps, nausea, chills, severe thirst, or inability to keep liquids down. Prevents all planned activities. Blood in the stool. |
Increase fluid intake. Use an antibiotic. Seek medical attention if symptoms do not improve or if blood in stool is present. |
(Chart adapted from The Journal of Travel Medicine’s published guidelines)
Increasing fluid intake and oral rehydration solution (ORS)
When managing TD, your primary goal is to prevent dehydration. At the first signs of diarrhea you should start increasing your fluid intake. Drink treated water and use an oral rehydration solution (ORS), a mixture of salt and sugar that’s designed to be rapidly absorbed by your intestines. You can get ORS packets from your pharmacy.
In healthy adults, most cases of TD do not cause significant dehydration, but some travellers are at increased risk of severe diarrhea and dehydration (such as young children, older adults, those with low stomach acid, inflammatory bowel disease, and taking high blood pressure medication).
Seek medical attention if signs of dehydration (excessive thirst, infrequent urination, dark-coloured urine, drowsiness, dizziness, or nausea) do not resolve with self-treatment.
Anti-motility agents and Bismuth subsalicylate
These products can be used when mild to moderate diarrhea occurs. Anti-motility agents such as loperamide (e.g. Imodium) and bismuth subsalicylate-containing products (e.g. Pepto-Bismol) are drugs that alleviate the symptoms of diarrhea, but they also have side effects.
It’s important to talk to your doctor before taking loperamide, as it can lead to cardiac events when the recommended amount is exceeded. The risk of a cardiac event also increases if taking loperamide with other medication such as quinine, ritonavir, erythromycin, and others. Loperamide should only be used in children over age 6.
Alternatively, Pepto-Bismol can be used to relieve diarrhea symptoms. As outlined above, constipation can occur and the medication is not recommended for pregnant women or children under 12.
Antibiotics
Use antibiotics to treat TD with caution. Antibiotics can be used if you have moderate to severe diarrhea and when the risk of diarrhea-related complications is high. Travellers to high risk destinations may consider packing emergency antibiotics for use in case TD becomes debilitating and prevents all planned activities.
Before you depart, make an appointment with your doctor or travel health specialist to discuss the use of antibiotics. Make sure you know how to identify the severity of TD and if needed, when antibiotics should be used. Depending on your destination, some antibiotics may not be recommended due to the presence of antibiotic resistance. For example, in Southeast Asia a common cause of TD is infection with Campylobacter spp.. However, the bacteria is now resistant to antibiotics, particularly fluoroquinolone antibiotics like ciprofloxacin, and is gaining resistance to other commonly prescribed antibiotics like azithromycin.
Contact a doctor if symptoms do not improve after taking the antibiotic.
Image by Hafidz, Pexels
Article by Claire Westmacott