Check-Up: Traveller's diarrhoea

Last year while travelling in South America, I was struck down with diarrhoea and vomiting. As I felt quite unwell I visited a local hospital and was told I had traveller’s diarrhoea.

Traveller’s diarrhoea is defined as the passing of three or more unformed stools within a 24-hour period. It may be accompanied by nausea, cramps and vomiting as well as bloody stools and faecal urgency. Headache and muscle pain may also be experienced. Most cases of the condition are mild and disappear without treatment within three to five days.

Traveller’s diarrhoea is estimated to affect up to 15 million people annually. It commonly occurs in those visiting developing countries where water supplies may be inadequately treated.

Are bacteria or viruses the most usual causes of this type of illness?

The condition can be either infective or non-infective and may be caused by bacteria, parasites or viruses. Organisms that cause the disorder are usually acquired from food or water and even from food prepared with infected water.

Some 75 per cent of traveller’s diarrhoea of less than two weeks’ duration is thought to be caused by bacteria. While the most common bacteria to cause the condition is E.coli, other bacteria such as campylobacter, salmonella and shigella can also be responsible.

Viruses have been found to cause about 20 per cent of cases of traveller’s diarrhoea, while parasites are thought to cause the remaining 5 per cent of cases.

What about those whose symptoms last for more than two weeks after they first get ill?

For those with symptoms lasting more than two weeks, non-infective causes may be to blame. These can include irritable bowel syndrome, inflammatory bowel disease, coeliac disease, as well as post-infective malabsorption.

Diagnosis is based on a good travel and clinical history. A stool sample for laboratory examination and blood, liver and kidney tests may also be carried out. Often, however, the cause remains unknown.

Rehydration is the most important part of treatment, while some sufferers may require treatment with antidiarrhoeal, antibiotic or antimicrobial medications.

As I’m due to travel back to the same region, have you any advice on how to avoid a recurrence?

As always, prevention is better than cure. When travelling to developing countries, it is advisable to drink only bottled water or carbonated beverages. Use bottled water for cleaning your teeth and avoid ice cubes and uncooked vegetables and fruit.