Entamoeba histolytica

For the infection and disease caused by this parasite, refer to Amoebiasis.Entamoeba histolytica is an anaerobic parasitic protozoan, part of the genus Entamoeba. It infects predominantly humans and other primates. It is estimated that about 50 million people are infected with the parasite worldwide. Diverse mammals such as dogs and cats can become infected but are not thought to contribute significantly to transmission. The active (trophozoite) stage exists only in the host and in fresh loose feces; cysts survive outside the host in water, soils and on foods, especially under moist conditions on the latter. When cysts are swallowed they cause infections by excysting (releasing the trophozoite stage) in the digestive tract.
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