What is Tapeworm Infection

Tapeworms are parasites that can live in your intestines. When eggs from a tapeworm are consumed, the eggs develop into a young tapeworm (larva) and eventually an adult tapeworm inside of the body.

An adult tapeworm can grow very long and can live inside of a human for many years. Tapeworm infection is rare in the United States.

There are several types of tapeworms. Most tapeworm infections cause only mild symptoms and are limited to the intestines. One type of tapeworm, called a pork tapeworm (Taenia solium or T. solium), can cause a more serious infection (cysticercosis). In this type of infection, tapeworm larvae can spread through the body and form cysts in areas such as the eyes, skin, muscle tissue, heart, and brain.

What are the causes?

This condition is caused by:

• Eating beef, pork, or fish that is raw or has not been cooked well enough.
• Drinking water that is contaminated with tapeworm eggs.
• Eating food that is contaminated with tapeworm eggs.

What increases the risk?

You are more likely to develop this condition if:

• You live in or travel to places where livestock roam freely, such as rural, developing countries.
• You work with animals or are exposed to animals.
• You live in a household with someone who has a tapeworm infection.
• You eat food that has been prepared by someone with a tapeworm infection.

What are the signs or symptoms?

In some cases, there are no symptoms. If you have symptoms, they may include:

• Pain in the abdomen.
• Nausea.
• Loss of appetite.
• Weight loss.
• Worm segments in your stool (feces).
• Diarrhea.

Symptoms of cysticercosis vary depending on where the cysts form in your body. Symptoms may include:

• Feeling lumps under your skin.
• Headache.
• Seizure.
• Confusion.
• Loss of vision.
• Muscle weakness.
• Balance problems.
• Eye pain.

How is this diagnosed?

This condition may be diagnosed based on:

• Your symptoms.
• Your travel history.
• Your diet history.
• Blood tests.
• Stool tests.
• Tests on the fluid that surrounds the brain and spinal cord (cerebrospinal fluid, CSF). The fluid is removed with a needle during a spinal tap (lumbar puncture).
• Imaging tests, such as a CT scan or MRI.

How is this treated?

Treatment for this condition depends on the type of tapeworm and your symptoms. Most often, this condition is treated with antiparasitic medicine to kill the tapeworms.

Treatment for cysticercosis depends on the number of cysts and the symptoms you have. Treatment may include:

• Medicines to:
  • Kill tapeworm larvae or eggs.
  • Decrease swelling (steroids).
  • Prevent seizures (anti-epileptics).
• Surgery to remove cysts.

Follow these instructions at home:

• Take over-the-counter and prescription medicines only as told by your health care provider.
• If you were prescribed an antiparasitic medicine, take it as told by your health care provider. Do not stop taking the antiparasitic even if you start to feel better.
• Keep all follow-up visits as told by your health care provider. This is important.
• Wash your hands often with soap and water. If soap and water are not available, use hand sanitizer.

How is this prevented?

• Do not eat raw or undercooked fish or meat. Cook fish and meat according to food safety guidelines. Use a meat thermometer to make sure that fish and meat are cooked to the recommended temperatures.
• Wash your hands with soap and water:
  • After you use the toilet.
  • Before you handle or prepare food.
  • After you handle or prepare food.
• Freeze meat for 12 hours before cooking it to help prevent tapeworm infection. Only eat raw fish (such as sushi) that has been previously frozen.
• Before you eat raw fruits and vegetables:
  • Wash them in boiled, bottled, or treated water.
  • Peel them.
• When traveling in developing countries:
  • Make sure you only drink water that is bottled or treated.
  • Do not eat or drink anything that may be contaminated, including beverages with ice cubes that may have been made from unboiled or untreated water.
  • Do not eat raw foods that have been washed in unboiled tap water.
  • It is safe to drink bottled or canned beverages, such as carbonated beverages, teas, pasteurized fruit drinks, or steaming hot beverages.

Contact a health care provider if you:

• Still have symptoms of tapeworm infection after your treatment is complete.
• Develop any new symptoms.

Get help right away if you:

• Have a seizure.
• Have sudden vision loss.
• Feel light-headed or you faint.
• Become confused.

Summary

• Tapeworms are parasites that can live in your intestines. Tapeworms can live in a human body for many years.
• Tapeworms develop from tapeworm eggs that are consumed. This can occur from eating beef, pork, or fish that is raw or has not been cooked well enough, or from eating food or drinking water that is contaminated with tapeworm eggs.
• Most tapeworm infections cause only mild symptoms and are limited to the intestines. One type of tapeworm can cause a more serious infection (cysticercosis) where the larvae spread through the body and form cysts.
• Most often, this condition is treated with antiparasitic medicine to kill the tapeworms.