Tapeworm infection

Tapeworm infection is caused by ingesting food or water contaminated with tapeworm eggs or larvae. If you ingest certain tapeworm eggs, they can migrate outside your intestines and form larval cysts in body tissues and organs (invasive infection). If you ingest tapeworm larvae, however, they develop into adult tapeworms in your intestines (intestinal infection).

An adult tapeworm consists of a head, neck and chain of segments called proglottids. When you have an intestinal tapeworm infection, the tapeworm head adheres to the intestinal wall, and the proglottids grow and produce eggs. Adult tapeworms can live for up to 30 years in a host. Intestinal tapeworm infections are usually mild, but invasive larval infections can cause serious complications.

Symptoms Causes Risk factors Complications Prevention

Many people with intestinal tapeworm infection have no symptoms. If you do feel the effects, your symptoms will depend on the type of tapeworm you have and its location. Invasive tapeworm infection symptoms vary depending on where the larvae have migrated.

Intestinal infection

Signs and symptoms of intestinal infection include:

  • Nausea
  • Weakness
  • Loss of appetite
  • Abdominal pain
  • Diarrhea
  • Weight loss and inadequate absorption of nutrients from food

Invasive infection

If tapeworm larvae have migrated out of your intestines and formed cysts in other tissues, they can eventually cause organ and tissue damage, resulting in:

  • Fever
  • Cystic masses or lumps
  • Allergic reactions to the larvae
  • Bacterial infections
  • Neurological signs and symptoms, including seizures

When to see a doctor

If you experience any of the signs or symptoms of tapeworm infection, seek medical attention.

© 1998-2015 Mayo Foundation for Medical Education and Research (MFMER). All rights reserved. Terms of use