By Dr Gerard Lalande
One of the most common afflictions to hit travellers to Southeast Asia, traveller's diarrhoea or Bangkok Belly, as it is somewhat less than affectionately known to expats living in the City of Angels, is essentially a benign illness that rarely required m
However, it can become serious in predisposed individuals or those who ignore the complications.
Statistics show that expats living in Southeast Asian countries often suffer from two to three transitory episodes of troublesome diarrhoea every year, although some progressively develop relative immunity to the common infectious agents.
Traveller’s diarrhoea (TD) is defined by at least 3 episodes of acute diarrhoea within 24 hours during or after the trip. It often starts 3 to 4 days after arrival or later, around the 10th day.
The soft or watery stool may be non-specific or contain some blood or pus. Other symptoms are often present and include abdominal pain, nausea and vomiting, urgent need to pass stool, headache and sometimes fever. Most cases of TD spontaneously improve within one to three days.
Complications, although rare, can and do occur with the loss of fluids and minerals induced by profuse diarrhoea and recurrent vomiting leading to severe dehydration that may require hospitalisation.
It’s essential to recognise early signs of dehydration, which include increased thirst, dry mouth, decreased urination with dark urine and intense weakness. If left untreated, especially in children, the elderly or individuals with chronic underlying disease, dehydration can lead to coma and life-threatening shock. Dehydrated babies and infants may simply present unusually slow behaviour with little urine (dry diaper) and no tears when crying. Other complications that mainly affect predisposed individuals are related to the pathogen’s invasive ability to damage other organs, which can lead to septic (infectious) shock.
In malaria endemic areas, diarrhoea with high fever in children may require special tests to rule out the presence of the malaria parasite.
Sometimes referred to as diseases from dirty hands, TD are food/water borne illnesses caused by various pathogens released by infected people in their faeces. Stress, jetlag and significant changes in diet related to the overseas trip may also be involved.
The most frequent microrganisms are bacteria, especially the E coli bacteria strain enterotoxigenic Escherichia coli (Etec). In 15 to 20 per cent of cases. the cause is a virus or a parasite.
For the majority of TD, the search for the pathogen is not needed and the most important measure is to maintain proper hydration by drinking safe mineral water. Sport drinks are appropriate and for those who are hit in a remote area, the tried-and-trusted “home remedy” consisting of one litre of water with 6 teaspoons of sugar and 1 of salt is an alternative. Most convenience stores also sell packets of oral rehydration solution and these can be safely mixed with bottled water.
To help control the number of episodes, anti-motility agents such as loperamide (Imodium) can be used but this type of medication may also delay the removal of pathogens from the GI tract and prolong the infestation. Antibiotics are indicated only when symptoms are severe (with fever, bloody stools, marked fatigue), or when the diarrhoea persists after 4 to 6 days. Infectious cases of TD are usually treated with fluoroquinolones (such as ciprofloxacin) and azithromycin antibiotics.
Prophylaxis with antibiotics is recommended only for those in the country for a short stay and only when the person must be in perfect condition throughout the entire visit, such as artists or sportsmen.
In some countries, a vaccine is available for cholera and TD caused by the Etec bacteria but its efficacy is quite low and it is mainly recommended for people working in areas when cholera is highly endemic.
Prevention lies in adhering to proper hygiene especially hand-washing (the only proven effective preventive method), eating at trusted restaurants and drinking clean water without ice-cubes made from tap water. In local food centres, it is wise to avoid raw or undercooked meat, fish or seafood as well as eggs or salads and fruit thatss already been peeled.. Street food sellers may have attractive foodstuffs to offer but the lack of running water in these places make the cleaning of the dishes and cutlery hazardous.
When eating adventurously along the streets, you need to keep the dictum in mind: Boil it, cook it, peel it or forget it.
Dr Gerard Lalande is managing drector of CEO-HEALTH, which provides medical referrals for expatriates and customised executive medical check-ups in Thailand. He can be contacted at firstname.lastname@example.org.