Amoebic dysentery is caused by the protozoan parasite 'Entamoeba histolytica'. Invasive intestinal parasitic infection can result in symptoms of fulminant dysentery, such as fever, chills, bloody or mucous diarrhoea, and abdominal discomfort. The dysentery can alternate, with periods of constipation or remission.

This form of dysentery, which traditionally occurs in the tropics, is usually much more chronic and insidious than the bacillary disease and is more difficult to treat because the causative organism occurs in two forms, a motile one and a cyst, each of which produces a different disease course.

Both forms of amoebic dysentery are treated with drugs that specifically kill the amebic parasites that thrive in the intestines.

Ingestion of cysts from food or water contaminated with faeces is the main route of transmission. Low standards of hygiene and sanitation, particularly those related to crowding, tropical climate, contamination of food and water account for high rates of infection.

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