What is traveller's diarrhoea?

Traveller’s diarrhoea can be defined as diarrhoea which occurs while visiting a developing country or shortly after returning from travel to such a country. There is a sudden onset of soft or watery stools (bowel motions), with nausea, vomiting, abdominal cramps or low-grade fever. It usually clears up within a few days, but people with ongoing symptoms may need medications and/or medical attention, depending on severity.

WHO definition

The World Health Organization (WHO) defines traveller's diarrhoea as occurring when there are:

• three loose bowel movements within eight hours; or
• four loose bowel movements within 24 hours, plus at least one sign or symptom of nausea, vomiting, abdominal cramps, faecal urgency, tenesmus (anal spasms and straining without passing a great amount) or mild fever.  

How many people are affected?

Traveller’s diarrhoea affects about 20% to 60% of travellers to tropical and semi-tropical areas, including Latin America, parts of the Caribbean, South and Southeast Asia and Africa. Traveller's diarrhoea usually occurs in the first two weeks of travelling from a low-risk region (eg, an industrialised country) to a high-risk region (a developing country).

In 80% of cases, without treatment, traveller's diarrhoea lasts about two to four days, but it may last much longer in some people. About 25% of affected people have to change their planned activities and about 30% can be confined to bed.

What causes it?

Diarrhoea is the symptom caused by your body's response to a sudden change in the bacteria hosted in your gut. Eating or drinking food or liquid containing pathogens (disease-causing bacteria, viruses or parasites) causes traveller's diarrhoea. Bacterial causes account for about 75% of all cases, with the bacterium enterotoxic Esherichia coli being responsible for 10% to 45% of these. Campylobacter, Salmonella, and Shigella make up the rest of the 'top four' bacterial causes.

Parasites cause about 5% to 10% of traveller's diarrhoea cases, and viral causes (particularly noroviruses and rotaviruses) make up about 20% of cases. Cholera, the disease that used to cause the most anxiety for travellers, now has a very low incidence in travellers (about 1 in 200,000), and is therefore of less concern for travellers than previously.

Related topics

Also see: Food and drink - safety tips for travellers and  Ten point plan for managing traveller's diarrhoea

Original content courtesy of Dr Marc Shaw, Medical Director, WORLDWISE Travellers Health Centres, New Zealand, from the Travel Medicine Guide, 6th edition, 2011. Edited by everybody, November 2011.