DIARRHOEA (TRAVELLER'S DIARRHOEA)

With thanks to Dr. Marc Shaw of the Traveller's Health Centre 72 Remuera Road, New Market, Auckland 09-520-5830 & Dr. Geoff Kivell (The Floating Doc) S/V "Aspect of Arran"

Disclaimer:

Whilst every effort is made to provide current and accurate information and advice,  no liability is accepted by the Island Cruising Association for any incorrect statement or advice.

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Diarrhoea in travellers, or Travellers' Diarrhoea (TD), is the most common infectious disease experienced by travellers, affecting approximately 50% of travellers from industrialised nations to developing countries each year. Diarrhoea in travellers can have many different causes and may not necessarily be due to microbes.

What is Travellers' Diarrhoea?

TD is a term often applied to any type of diarrhoea in travellers, irrespective of cause. Classically TD is an illness with non­bloody diarrhoea, without fever, that starts within 1 or 2 weeks of arrival in a developing country and lasts for 3-5 days. Travellers' Diarrhoea is defined as greater than or equal to 3 loose bowel motions (stools) within 8 hours or greater than or equal to 4 within 24 hours... plus 1 of nausea, vomiting, abdominal cramps, mild fever.

The point of this definition is that many travellers assume that ANY loose motion is Travellers Diarrhoea and they may tend to self-treat unnecessarily. TD can vary from just a few extra­loose bowel movements per day, to an illness with profuse bloody diarrhoea and fever (dysentery). Dysentery occurs in up to 10% of persons. Of those affected, it is estimated that 30% will be confined to bed and 40% will have to curtail their activities. In warm climates dehydration can be severe, even fatal, particularly in children.

Because human behaviour is the main risk factor for Travellers' Diarrhoea, little can be done to prevent the most common forms of diseases. There has recently been a new vaccine into New Zealand and Australia that prevents against a common form of TD (see below).

Where does Travellers' Diarrhoea occur?

TD is seen in visitors to virtually any country with only New Zealand, Australia, Japan, Northern Europe, Canada and the USA being regarded as low risk destinations. Colourful descriptions for TD common in travellers to particular destinations (Bah belly, Inca quick-step, Montezuma's curse etc.) usually apply to TD caused by local bacteria in the particular country or destination. These 'local' bacteria are a special type of bacterium called E coli which produce a toxin that causes diarrhoea, the so-called Entero Toxigenic E.Coli (ETEC). ETEC is the commonest cause of TD in most studies (40-75% of cases), but this varies depending on the area. For example, some studies have shown it to be more common in Latin American and African countries than Asia.

How do you catch Travellers' Diarrhoea?

Contaminated water or food usually spread the microbes that cause TD.

Are there any risk factors for getting Travellers' Diarrhoea?

There are a number of risk factors for getting the disease whilst travelling abroad, including:

1. travel to certain areas of tropical Africa, Latin America and Asia
2. risky behaviour in eating and drinking i.e. ignoring alimentary hygiene with attention to food and water.
3. travel to an area during the summer or wet season
4. age of the travellers greater than 30 years

What is the incubation period (time from exposure to first symptoms)?

10 hours to 3 days.

How is Traveller's Diarrhoea diagnosed?

This is by laboratory tests to find the offending microbe in the faeces of an infected person. In practice, tests are only done in cases with severe or persistent illness. In many cases a cause for the diarrhoea may not be found.

What is the treatment?

The currently recommended management of TD in adults and children is basic and remains largely the same, but with revisions depending on updated microbial antibiotic resistances. The most important aspect of the management of TD at any age is proper hydration, by either oral or intravenous administration as appropriate to the level of the traveller's dehydration. Various commercially­made or homemade fluid preparations can be used. Travellers are advised to plan a management schedule along the following lines, in case they get TD whilst abroad. Whilst antibiotics can also be given it needs to be noted that fluid replacement is THE most important first line management.

Travellers' Diarrhoea is usually treated with a series of measures such as:

•  fluids to replace the amounts lost through diarrhoea and vomiting: e.g. electrolytes, juices ( apple and carrot ).
• anti-diarrhoeal medication such as loperamide.
  
• antibiotic medication such as norfloxacin, doxycycline or co­trimoxazole, which need to be taken with medical supervision.

"Ten Top Stoppers"

1. Alimentary Hygiene is simple and DOES work but is not a 'practical reality’ for most travellers. Wash hands before eating and after toileting, if unsure then cleanse eating utensils before using them... thus any information needs to be easy to apply and symbiotic with the traveller's journeying e.g. Hand-washing

2. Most instances of TD are mild and of short duration and will not need specific management ... thus simple easy-to-use information on management is 'first-line' therapy

3. Drink lots of fluids and salts, especially if at risk for dehydration ... thus consider:
   
   * Soups and sugar-flavoured mineral waters
   
   * The WHO recommended formula for prevention of dehydration: 1 teaspoon salt + 8 teaspoons sugar in 1 litre of potable water
   
   • Bottled or canned fluids, teas or 'clean' water
   
   • Avoid milk and milk products for 24-48 hours

4. The WORLD HEALTH ORGANIZATION (W.H.O.) have described a SIMPLE FORMULATION FOR FLUID REPLACEMENT ... it is a good 'first line' and practical measure for preventing TD. Prepare 2 separate glasses of the following:
   
   * Glass 1: 200 mls Orange, apple or other fruit juice (rich in potassium), + 1/2 teaspoon Honey (contains glucose) + 1 pinch salt (contains sodium)
   
   * Glass 2: 200 mls Water (carbonated/ boiled), + 114 teaspoon Baking soda (contains bicarbonate)
   
   Drink alternatively from each glass until thirst is quenched. Supplement as desired with carbonated beverages, water or tea made with boiled/carbonated water. Avoid solid foods and milk until recovery occurs. It is important that infants continue breast feeding and receive water as desired if they are receiving these two solutions.

5. Food should be started as soon as the patient can eat. The complete withdrawal of food during diarrhoea is not recommended. Consider: Rice, bananas, papaya, stewed apples, dry salty biscuits, and pumpkin.

6. Oral Rehydration Solutions (ORS) are important for children, the elderly and anyone with cholera-like diarrhoea because of the contained electrolytes and sterility of the mixture ... HOWEVER in adults ORS have little or no influence on symptoms, thus soups, juices and the like are adequate.

7. Wait until get ongoing diarrhoeal symptoms before treating ... 3 loose motions in 8 hours or 4 within 24 PLUS at least one of: nausea, vomiting, abdominal cramps, or mild fever.

8. The use of anti-motility medication, to be used in the 'initial stages' of TD, before antibiotics.
   
   * Loperamide and Diphenoxylate will slow down the bowel-muscle contractions ... thus the patient will have fewer motions but will continue to lose fluid into the bowel, and so underestimate fluid loss.
   
   * Loperamide has a mild anti­secretory action, and is the preferred drug to Diphenoxylate, which has more adverse reactions (especially those relating to opiate and anticholinergic effects)

9. Antibiotics can have an important place in TD. An effective antibiotic will relieve symptoms and shorten the illness, especially in
   cases of diarrhoea caused by organisms such as Shigella or E. coli Antibiotics alone are suggested where the diarrhoea is:
   
   • Accompanied by a fever of > 38 degrees Celsius.
   
   * Accompanied by blood in the motion. (this is a serious sign and needs medical assessment)
   
   • Accompanied by 3-5 motions in a 24-hour period.
   
   • Unchanged after two days most diarrhoeal illness that are not dysenteric respond to single-dose antimicrobial therapy

10. With TD parameters being met, the following is a self-treatment formula for ADULT MANAGEMENT:

Loperamide + antibiotic combo. = illness will then generally last less than 2 hours.

If using this formula then the following dosages are recommended

Dosages: Loperamide 2 mgs
Stat: i stat
Ongoing: 4 hourly (max 16 mgs/day)

Antibiotic combinations:
2 x 80TMP/40OSMX or ii BD, 3 days

TMP = Trimethoprim
SW = Suphamethoxazole

11. Antimicrobials (antibiotics) used in TD:

A. The following are used to treat TD, but need to be prescribed by a Doctor: Azithromycin, Ciprofloxacin, Norfloxacin, Cotrirnoxazole

B. Routine prophylaxis for TD is not indicated unless the intending traveller has: • AIDS 1 HIV or is immune compromised.

• Inflammatory bowel disease
• A history of stomach surgery
• Or is using either a proton pump inhibitor OR H2 receptor antagonist
• Insulin dependant diabetes
• Essential business or sport that cannot be compromised with illness
• Heart disease and on diuretics

Maximum duration of antibiotic prophylaxis, under medical guidance, is 3 weeks

How do you prevent Travellers' Diarrhoea?

Remember the adage:

COOK IT, BOIL IT, PEEL IT OR AVOID IT!!

• Drink bottled purified or carbonated water for drinking and cleaning teeth. Make sure that bought bottled water is appropriately sealed. Regular water (at sea level) should be brought to boiling point for one minute before it is safe to drink.

• Avoid ice in drinks and remember that refreshing ice blocks and flavoured ices may be made with contaminated water.

• Foods should be thoroughly cooked and served piping hot. Be very wary of food sold by street vendors!

• Avoid raw seafood and shellfish, even though they may have been preserved with vinegar, lemon or limejuice.

• Choose raw vegetables and fruits that you can peel yourself. Avoid salads unless they have been made by you! Do not forget to wash your hands with soap or hand cleanser first and do not eat the peelings!

Is there a vaccine available in Australia and New Zealand?

Yes there is a vaccine called DUKORAL. It provides up to 60­80% protection against the most common organism (ETEC) for three months.

Disclaimer:

Whilst every effort is made to provide current and accurate information and advice, no liability is accepted by MASTA New Zealand or its clinical subsidiary (Worldwise Travellers Health and Vaccination Centres of New Zealand for any incorrect statement or advice.)