Taeniasis

• Illustrations
• Alternative names
• Definition
• Causes, incidence, and risk factors
• Symptoms
• Signs and tests

• Treatment
• Expectations (prognosis)
• Complications
• Calling your health care provider
• Prevention

Alternative names    Return to top

Definition    Return to top

Taeniasis is a tapeworm infection.

Causes, incidence, and risk factors    Return to top

Tapeworm infection is acquired by eating raw or undercooked meat of infected animals. Beef generally carry Taenia saginata while pigs carry Taenia solium. The larvae from the infected meat develop in the human intestine into the adult tapeworm -- which grows and can attain lengths greater than 12 feet.

Tapeworms are segmented, with each segment (proglottid) capable of producing eggs. Eggs are dispersed by individual or groups of proglottids detaching and passing out with the stool. The groups of proglottids from the beef tapeworm are capable of movement and actively crawl out through the anus.

Adults and children with tapeworm (T. solium, pork tapeworm only) can, if appropriate hygiene is lacking, become self-infected by ingesting eggs from their tapeworm which were picked up on their hands while wiping or scratching the anus.

Additionally, these individuals can expose other individuals to T. solium eggs, usually via food handling. Ingested eggs hatch in the intestinal track and the larvae migrate through the tissues, where they encyst. If larvae migrate to the brain, they can cause seizures and other neurological problems. This condition is called cysticercosis.

Certain freshwater fish and salmon may also carry a tapeworm called Diphyllobothrium latum (see diphyllobothriasis).

Symptoms    Return to top

Tapeworm infestation does not usually cause any symptoms. Infection is generally recognized when the infected person passes segments of proglottids in the stool, especially if the segment is moving.

Signs and tests    Return to top

• stool examined for ova (eggs) of Taenia solium or Taenia saginata
• segments of worm, "proglottids," may also be visible in stool
  • Taenia saginata proglottids may move around visibly

Treatment    Return to top

Tapeworms are treated with oral medications, usually in a single dose. The drug of choice for tapeworm infections is niclosamide. Praziquantel and albendazole can also be used.

Expectations (prognosis)    Return to top

Complete eradication of the tapeworm occurs following treatment.

Complications    Return to top

• self-infection with tapeworm eggs -- cysticercosis (T. solium only), which may cause seizures
• rarely, worms may cause obstruction of the intestine

Calling your health care provider    Return to top

Call for an appointment with your health care provider if you pass something in your stool that looks like a white worm.

Prevention    Return to top

In the U.S., laws governing feeding practices and inspection of domestic food animals have largely eliminated the problem of tapeworm. Adequate cooking of meat destroys the tapeworm larvae and will prevent infection by tapeworm. Good hygiene and hand washing after using the toilet will prevent self-infection in a person already infected with tapeworms.