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Johns Hopkins Symptoms and Remedies

Johns Hopkins Medicine

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Tapeworm Infestation

What is it?

Three common types of tapeworms (flat, segmented worms) can inhabit the digestive tract of humans: Diphyllobothrium latum (fish tapeworm), Taenia saginatum (beef tapeworm), and T. solium (pork tapeworm). Once inside the intestine, a tapeworm attaches itself to the intestinal wall with the suction cups and hooks on its head, and absorbs food through the entire surface of its body. Tapeworms vary in length from less than an inch to more than 30 feet, and some may survive for over 25 years in the body. Tapeworm larvae are most often ingested while eating raw or undercooked fish, beef, or pork; poor sanitary practices increase the risk of infestation. In humans, the adult worm remains in the intestine; however, the larvae of some tapeworms such as T. solium may form cysts (known as cysticercosis) in organs throughout the body—especially the brain. While tapeworm infestation generally causes few if any symptoms, the cysts formed by the larvae may produce serious and widespread symptoms. Tapeworm infestation, although unpleasant, is easily treated.

What Causes It?

  • Tapeworm infestation most commonly occurs as a result of ingesting raw or undercooked freshwater fish, beef, or pork that contains tapeworm cysts.
  • Fish from lakes polluted with raw sewage are more likely to be infested.
  • Poor sanitary conditions may promote infestation by tapeworm eggs.

Prevention

  • Thoroughly cook fish, beef, and pork before eating.
  • Avoid dishes made with raw meat or fish, such as steak tartare, sushi, ceviche, or inadequately cooked gefilte fish.
  • Wash hands vigorously with soap and warm water after using the toilet and before handling food.

Diagnosis

  • Patient history and physical examination.
  • Stool samples to detect eggs or worm segments.
  • Abdominal x-rays. X-rays may be taken of other areas if cysticercosis is suspected.
  • CT (computed tomography) or MRI (magnetic resonance imaging) scans may be done to detect cysts in the brain.

How to Treat It

  • Worm-killing medications, such as praziquantel, are prescribed. Duration of treatment and strength of dosage depend upon the type of tapeworm.
  • Albendazole is recommended for cysticercosis.
  • Injections of vitamin B12 may be administered to treat pernicious anemia associated with fish tapeworm infestation.
  • Surgery is sometimes performed to excise cysts.
  • Corticosteroid drugs may be prescribed to treat inflammation caused by a cyst.
  • Anticonvulsant drugs may be prescribed to control seizures if brain infection is present.

When to Call a Doctor

  • Call a doctor if you notice worm segments or eggs in your stool or clothing, or if you develop unexplained hunger, fatigue, nausea, abdominal pain, or seizures.