International travel and health



Caused by the protozoan parasite Entamoeba histolytica.


Transmission occurs via the faecal–oral route, either directly by person-to-person contact or indirectly by eating or drinking faecally contaminated food or water.

Nature of the disease

The clinical spectrum ranges from asymptomatic infection, diarrhoea and dysentery to fulminant colitis and peritonitis as well as extraintestinal amoebiasis.

Acute amoebiasis can present as diarrhoea or dysentery with frequent, small and often bloody stools. Chronic amoebiasis can present with gastrointestinal symptoms plus fatigue, weight loss and occasional fever. Extraintestinal amoebiasis can occur if the parasite spreads to other organs, most commonly the liver where it causes amoebic liver abscess. Amoebic liver abscess presents with fever and right upper quadrant abdominal pain.

Geographical distribution

Occurs worldwide, but is more common in areas or countries with poor sanitation, particularly in the tropics.


Food and water hygiene (Chapter 3). No vaccine is available.