Fortunately, most exposed people do not become seriously ill. The mild form of amebiasis includes nausea, loose stools, weight loss, abdominal tenderness and occasionally fever. In rare cases, the parasite will invade the body beyond the intestines and cause a more serious infection, such as a liver abscess. The symptoms may appear from a few days to a few months after exposure but usually within 2 to 4 weeks. Some people with amebiasis may carry the parasite for weeks to years, often without symptoms.
Infected people are the only source of the parasite.
Fecal material from infected people may contaminate water or food and may serve as a vehicle to infect others. Animals are not infected with or carry the parasite, although, in some parts of the world, flies may serve to transfer cysts from human stool to fruits and vegetables. Examination of stools under a microscope is the most common way for a doctor to diagnose amebiasis. Specific antibiotics can be prescribed by a doctor to treat amebiasis. Generally, it is not necessary to exclude an infected person from work or school.