Amebiasis

About This Disease

Amebiasis is an illness caused by a one celled parasite called Entamoeba histolytica. Most people who are infected with E. histolytica will not become sick from the infection. When illness occurs, it usually causes diarrhea and stomach cramping.

Signs and Symptoms

The symptoms of amebiasis are often quite mild and usually include loose stools (diarrhea), stomach pain and cramping, and weight loss. More severe illness is called amebic dysentery and includes stomach pain, bloody diarrhea and fever. In rare instances, the parasite can cause more serious infections, such as liver disease. The symptoms usually appear 2 to 4 weeks after infection with the parasite, but the onset may range from a few days to over a year.

Transmission

Amebiasis is spread person to person by eating or drinking food or water contaminated with the stools of persons infected with E. histolytica. It can also be spread through sexual contact with an infected person. While anyone can get this illness, it is most common in people who live in or travel to developing countries that have poor sanitary conditions.

For most persons, staying home from work or school is not necessary. However, persons who work as food handlers, child care providers, and those involved with patient care, should not serve or handle food until given permission to do so by their doctor or the Department of Health.

Diagnosis

If you have symptoms of amebiasis, your health care provider may conduct a stool specimen test.

Treatment

A doctor can prescribe medicine to treat amebiasis.

Immunity

If you are re-infected with E. histolytica, you could become sick again.

Risk in Hawaii

Rare, minimal cases have been reported.

Prevention

Practice good hygiene. Wash your hands often, especially after using the restroom and before handling food. Dispose of human wastes in a sanitary manner. Avoid sexual practices that may permit fecal-oral transmission.

When traveling to a country with poor sanitary conditions, follow these rules:

  • Drink only bottled, boiled, or filtered and treated water or sodas in cans or bottles. Do not drink fountain drinks or any drinks with ice.
  • Do not eat fresh fruit or vegetables that you did not peel yourself.
  • Do not eat or drink milk, cheese or other dairy products unless you are certain they have been pasteurized.
  • Do not eat or drink anything sold by street vendors.

Additional Resources

Information for Clinicians

Centers for Disease Control and Prevention (CDC)

Clinical Description: Infection of the large intestine by Entamoeba histolytica may result in an illness of variable severity ranging from mild, chronic diarrhea to fulminant dysentery. Infection also may be asymptomatic. Extraintestinal infection also can occur (e.g., hepatic abscess).