Amebiasis

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Amebiasis, widespread human disease in tropical regions, resulting from infection by the amoeba Entamoeba histolytica. The parasite most commonly is acquired in its encysted form in tainted food or drink. When it only infects the intestines it can cause dysentery, but it may also spread to other organs. Amebiasis is easily dealt with by drugs, but if untreated it can lead to abscesses of the liver, the lungs and, less frequently, the heart; rarely, it may even reach and damage the brain.

At least six forms of amoeba are parasitic in humans. Most important of these is Entamoeba histolytica, which causes amebiasis and dysentery. The diseases often occur in epidemics when raw sewage contaminates water supplies or when soil is fertilized with untreated human wastes.

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