Trichinosis

Trichinosis is an infection caused by a roundworm known as Trichinella spiralis.

What is going on in the body?

The Trichinella spiralis roundworm is found in almost every meat-eating mammal. People usually become infected when they eat poorly cooked or raw meat, especially pork. The larvae of the worm are found in cysts, or small capsules, in the meat. The individual's stomach juices dissolve the cyst and free the larvae. The larvae grow and mate in the person's bowels. The female worms produce more larvae, which go from the bowels into the person's blood. The larvae can go from the blood vessels into the muscles and form new cysts.

What are the causes and risks of the infection?

Trichinosis is caused by the roundworm Trichinella spiralis. Eating raw or inadequately cooked meat increases the risk of acquiring trichinosis.

What are the signs and symptoms of the infection?

Most of the time, trichinosis occurs without symptoms. Some people just have an upset stomach, joint pain, and muscle aches. If there are many larvae, the person may have more severe symptoms, such as:

When the worms leave the intestines and migrate through the tissues, symptoms can include the following:

Rarely, serious problems involving the heart, central nervous system, and lungs occur.

How is the infection diagnosed?

Diagnosis of trichinosis begins with a medical history and physical exam. The healthcare provider may order the following tests:

What can be done to prevent the infection?

Trichinosis is prevented by thoroughly cooking meats, especially pork. Meat should be cooked so that all parts of it reach 150 degrees Fahrenheit. The larvae can also be killed by freezing the meat at 16 degrees Fahrenheit for 36 hours.

What are the long-term effects of the infection?

Long-term effects and death from trichinosis are very rare. Although the worm can infect vital organs, such as the heart, lungs, and brain, this rarely happens.

What are the risks to others?

Trichinosis is not spread from person to person.

What are the treatments for the infection?

There is no treatment that will eliminate the trichinosis infection. If it is diagnosed early, the healthcare provider may prescribe thiabendazole to dislodge some of the worms. Steroids, such as prednisone, may be also used.

What are the side effects of the treatments?

Thiabendazole can cause diarrhea and stomach upset. Steroids can cause high blood glucose and an increased risk of infection.

What happens after treatment for the infection?

Most people recover completely from trichinosis. Most symptoms disappear by the third month. Vague muscular pains and tiredness may persist for months.

How is the infection monitored?

Any new or worsening symptoms should be reported to the healthcare provider.

Author:Danielle Zerr, MD
Date Written:
Editor:Ballenberg, Sally, BS
Edit Date:06/30/01
Reviewer:Eileen McLaughlin, RN, BSN
Date Reviewed:06/11/01