Amebiasis Amebiasis, which is caused by a protozoan parasite, occurs worldwide, especially in regions with poor sanitation. This potentially serious illness is caused by parasites that invade the wall of the large intestine, causing either acute dysentery or chronic diarrhea of variable severity. The parasites can also infect the liver, causing inflammation and liver abscess. In the carrier state, which is common, parasites live in the intestine without causing symptoms. Transmission occurs through ingestion of fecally contaminated food or water.
Flies can serve as carriers of the amebic cysts.
Infected food handlers can spread the disease. Signs and Symptoms Symptoms of amebiasis are variable. You may be carrying the parasites and have no symptoms whatsoever. Mild illness causes crampy abdominal pain, little or no fever, and semiformed, foul-smelling stools. Mucus may be present but usually without blood.