Travellers' diarrhoea (TD) is a condition characterised by a marked increase in the frequency of unformed bowel movements and is commonly accompanied by abdominal cramps, urgency, nausea, bloating, vomiting, fever, and malaise.

It occurs in up to a half of European travellers who spend two or more weeks in developing parts of the world and should therefore be taken seriously.

Episodes of TD usually begin abruptly, occur during travel or soon after returning home, and are generally self-limiting. The onset of TD is usually within the first week of travel, but can occur at any time during the visit and even after returning home.

The most important determinant factor is the destination of the traveller. High-risk destinations include most of Latin America, Africa, the Middle East, and Asia, where attack rates of up to 50% have been reported.

TD is slightly more common in young adults than in older people but attack rates are similar in men and women. It is possible for travellers to experience more than one episode of TD during a single trip but rarely is it life threatening.

TD is usually acquired by ingestion of faecally contaminated food or water, or both. Both cooked and uncooked foods may be implicated if they have been improperly handled. The place in which food is prepared appears to be an important variable, with private homes, hotels, restaurants, and street vendors are listed in order of increasing risk.

Particularly risky foods include raw or undercooked meat, poultry, seafood, raw fruits and vegetables. Tap water, ice, and unpasteurized milk and dairy products are also associated with increased risk of TD. In the UK, we drink water straight from the tap and rarely consider that the water may be the source of disease but when the cleanliness of a water supply is in doubt, only adequately purified water should be drunk.

Worldwide, unsafe drinking water is a major problem. However, international travelers should not become hysterical about avoiding all water whilst traveling abroad. Most of the general information sites for travelers recommend to avoid drinking water anywhere abroad. But to avoid water where it is safe, could be as annoying, as dangerous to drink it where is not safe.

Safe Water for International Travelers (SWIT) - is an independent organization that provides the best available information about water safety around the world. Information is gathered from the most important and trustworthy sources.

Safe beverages include bottled carbonated beverages (especially beverages like Coke and Fanta), beer, wine, hot coffee or tea, or water boiled and appropriately treated with iodine.

TD typically results in four to five (sometimes more) loose or watery stools per day. The average duration of diarrhoea is 3 or 4 days but about 10% of the cases persist longer than a week and approximately 15% of cases experience vomiting, and up to 10% have diarrhoea accompanied by fever or bloody stools, or both.

Most food related illness is due either to a change in the amount or type of food, or an infection caused by eating contaminated food. Infectious agents (Bacteria, Viruses & Protozoans) are the primary cause and people travelling from developed to developing countries frequently experience a rapid and dramatic change in the type of organisms in their gastrointestinal tract.

These new organisms often include potential enteric pathogens and those who develop diarrhoea have usually ingested sufficient virulent organisms to overcome their individual defence mechanisms, resulting in symptoms.

The organisms most commonly associated with traveller's diarrhoea are; E.Coli, Salmonella, Campylobacter, Shigella, Rotavirus and Giardia.

Prevention of Travellers Diarrhoea

No vaccines are available and none are expected to be available in the near future that are effective against TD.

The use of prophylactic antibiotics is not recommended for travellers since there is little evidence to show that they are widely effective in preventing TD and there are potential drawbacks which include include allergic and other side effects and the possibility of developing resistance.

A new product has been developed and is currently being launched in Australia that has been clinically proven to reduce the risk of E.coli caused TD (current TGA regulations prohibit the use of the words Prevents or Protects). The product is called Travelan. More information on Travelan can be found HERE.

However, most evidence shows that meticulous attention to hygiene during food and beverage consumption can greatly decrease the likelihood of developing TD. Many travellers, however, encounter difficulty in observing these restrictions.

Some useful precautions include:- Unless you are sure of the purity of the water supply, don't drink it. This also applies to water used for ice-cubes and for cleaning teeth. Water from sealed lid bottles is usually safe, as are hot tea and coffee, fizzy drinks, beer and wine. Take care with local cheeses and ice cream. Boil unpasteurised milk before use. Cook meat thoroughly and eat while still hot. Avoid leftovers. Fish and shellfish may be hazardous even if well cooked. Take local advice, but avoid seafood if in doubt. Eat only cooked vegetables and avoid salads. Peel all fruit, including tomatoes. Avoid food exposed to flies. Wash all dishes and cutlery in clean, hot water. Wash your hands thoroughly before eating or handling food, and always after using the toilet.

Furthermore, our intestinal flora are thought to play an important role in protecting us against infection and managing immunity. They also provide specific enzymes needed to digest particular substances in the diet. Many digestive health problems including TD can escalate as our fragile intestinal flora is disturbed by the environmental and dietary changes associated with foreign travel. Travellers can minimise these digestive health risks by departing with a well balanced and healthy intestinal flora and by maintaining this protective shield throughout their travels. Travla is an advanced probiotic formulation from DTECTA Probiotics specifically developed for travellers as an effective means to ensure a healthy and well balanced intestinal flora by strengthening the healthy balance of friendly bacteria in the gut and enhancing its protective capacity and by selectively binding to harmful bacteria and flushing them out. DTECTA Travla probiotic can be obtained over the counter from many pharmacies in the UK. The usual dosge is; two capsules each day at mealtimes, starting one week before departure and continuing during travel abroad. For those travellers unfortunate enough to suffer from an upset tummy abroad there is now a natural alternative to anti-motility drugs such as loperamide & Imodium. While these drugs block the intestines to stop the diarrhoea, there is a natural probiotic yeast called Saccharomyces boulardii which will help flush out pathogens such as e coli and salmonella off the intestinal wall lining, and stop diarrhoea naturally. The first product in the UK to include Saccharomyces boulardii is called DiarSafe, from DTECTA Probiotics, and is priced lower than Imodium. Ask your local health food store or pharmacy for DiarSafe. Dosage is one to two capsules per day depending on severity of symptoms. For more information about DTECTA and other related products, visit their website here.

Treatment of Travellers Diarrhoea

Travellers with TD have two major complaints for which they desire relief; abdominal cramps and diarrhoea.

Oral Rehydration Solution (ORS)

Most cases of diarrhoea are self-limiting and require only simple replacement of fluids and salts lost in diarrhoeal stools. This is best achieved by the use of oral rehydration solution such as Dioralyte, Electolade, Rehidrat, or similar, which is available in sachets of powder at stores or pharmacies in almost all countries and must be prepared by adding the contents of a sachet to boiled or treated water.

The instructions should be checked carefully to ensure that the powder is added to the correct volume of water. This solution is appropriate for treating as well as preventing dehydration and should be consumed or discarded within 12 hours if held at room temperature or 24 hours if kept refrigerated.

Travellers should be advised to avoid iced drinks and non-carbonated bottled fluids made from water of uncertain quality. Milk can aggravate diarrhoea in some people and travellers with diarrhoea should avoid it.

Antimotility Agents

Such as loperamide and codeine come in convenient dosage forms and provide prompt symptomatic but temporary relief of uncomplicated TD by inhibiting intestinal movements.

They slow down the motility of the gut and increase fluid absorption by normalising the transit through the gut and restoring normal stools. They also diminish diarrhoea and shorten its duration thereby reducing fluid loss at the same time.

Antimotility agents relieve discomfort and social disruption and are safe and effective for otherwise healthy adults. They are best used when sanitary arrangements are difficult such as a long journey.

Self medication with antimotility agents is appropriate following sudden onset of increased bowel action with loose watery stools in persons over 12 and under 75 years of age who were previously in good health and not suffering from any other serious illness.

However, they should not be used by people with high fever, with blood in the stools, or if there is vomiting and dehydration. They should be discontinued if symptoms persist beyond 48 hours or they could make the illness worse.

Medical assistance (if available) should always be sought if any of the following occur:-

• There is blood in the faeces
• There is a fever
• The sufferer becomes confused
• The diarrhoea does not settle within 72 hours

However, medical assistance is not always available and the sufferer must decide whether or not to be treated using available antibiotics.

Antibiotic Treatment

travellers who develop severe and prolonged diarrhoea especially if associated with nausea, vomiting, abdominal cramps, fever, or blood in the stools, would benefit greatly from antibiotic treatment. Nausea and vomiting without diarrhoea should not be treated with antibiotics.

The most likely antibiotic regimen to be effective against enteric bacterial infection is ciprofloxacin (500mg taken twice a day), whilst metronidazole (800mg taken three times a day) is usually effective against protozoan infection. There is no antibiotic treatment effective against viral infection.

The biggest problem facing the sufferer is being able to accurately diagnose the cause which is virtually impossible without medical training. Since the symptoms of bacterial infections develop much more rapidly than protozoan infections it is safe to assume that a sudden onset is a bacterial infection.

In this situation treatment should consist of ciprofloxacin 500mg twice a day but if no improvement is seen within three or four days the sufferer should be switched to metronidazole 800mg three times a day.

It must be stressed that this treatment is to be undertaken in emergencies only when there is no chance of getting immediate medical assistance.