Amebiasis is an intestinal infection. It is normally spread when someone eats or drinks something that has with a microscopic parasite called Entamoeba histolytica (E. histolytica). The parasite is an amoeba, a single-celled organism. This is how illness got its name.
In many cases, the parasite lives in a person's large intestine and does not cause any symptoms. It can enter the lining of the large intestine and cause bloody diarrhea, stomach pains, cramping, nausea, loss of appetite, or fever. In rare cases, it can spread into other organs such as the liver, lungs, and brain.