Trichinosis

Trichinosis (trichinellosis) is an illness you can get if you eat undercooked meat from infected animals, particularly pork. The larvae of a type of roundworm called Trichinella cause it.

An estimated 10,000 people per year get trichinosis worldwide. It’s very rare in the U.S. due to the proper meat preparation.

You can’t tell if the meat you’re eating has worms just by looking at it. But taking precautions when handling and cooking meat can greatly reduce your risk of getting trichinosis.

Symptoms of trichinosis

Symptoms of trichinosis range from very mild to severe. You may mistake a mild case of it for the flu or other common illnesses.

Early symptoms of trichinosis, which start a few days after eating infected meat, may include:

• Nausea and vomiting
• Diarrhea
• Pain in your abdomen

Later symptoms may begin about two weeks after you eat the infected meat. They may last for several weeks. They include:

• Muscle soreness
• Fever and chills
• Headaches
• Swelling around your eyes
• Extreme tiredness
• Diarrhea or constipation
• Cough
• Rash or itchy skin

If you’ve eaten raw or undercooked meat and have these symptoms, contact your healthcare provider.

Trichinosis causes

The larvae of the Trichinella roundworm cause trichinosis. They’re a type of parasite.

If you eat Trichinella-infected meat, your stomach acid and enzymes break down the hard outside shell (cyst) of the larvae. This frees the adult worms. The worms then make larvae. The larvae live in your body tissues, especially your muscles. Your body then has an allergic reaction to the larvae.

These larvae can get into your body from:

• Eating raw or undercooked pork products
• Eating improperly stored meats
• Eating raw or undercooked meat from wild animals that are infected

What animals carry trichinosis?

Animals that can be infected with Trichinella roundworm include:

• Armadillos
• Bears
• Brown rats
• Cats and dogs
• Deer, moose and elk
• Many types of birds
• Pigs and boars
• Walruses

You can only get trichinosis if you eat raw or undercooked meat of an infected animal.

Complications of this condition

Severe cases of trichinosis can cause serious complications, like inflammation and damage to your:

• Heart muscle, which could result in irregular heart rhythm and/or heart failure
• Brain, which could result in seizures
• Lungs, which could cause severe breathing problems

In rare cases, heart and brain inflammation can lead to death.

How doctors diagnose this condition

Your healthcare provider might diagnose you with trichinosis based on:

• Your signs and symptoms
• Whether you may have eaten infected meat
• Blood tests that show high levels of eosinophils, a type of white blood cell

Antibodies to Trichinella don’t show up at first. But your provider might order blood tests later that will find the antibodies and confirm the diagnosis. Stool (poop) samples don’t help diagnose trichinosis.

In very rare cases, your provider may do a muscle biopsy to confirm it.

How is it treated?

Trichinosis treatment should begin as soon as possible. Some cases of trichinosis go away on their own. But severe, untreated cases can be fatal.

Your healthcare provider might prescribe:

• Pain relievers, like NSAIDs
• Medicines to help with inflammation, like steroids
• Medicines to get rid of parasites, including mebendazole and albendazole

If you take medication to deal with the parasites within the first three days of being infected, they can stop the infection from getting to your muscles.

What can I expect if I have this condition?

The prognosis (outlook) for someone with trichinosis is generally good with treatment. But it may take two to six months to feel completely better. Even with treatment, you might have long-term complications, including issues with your eyes, muscles and nerves.

The outlook for severe cases that result in brain or heart damage is poor. These cases can be fatal.

Can this be prevented?

You can take several steps to prevent trichinosis. These mainly involve preparing, cooking and storing meat properly. Be sure to:

• Cook meat thoroughly: Always use a food thermometer. The USDA recommends cooking pork to 160 degrees Fahrenheit. Cook game meat, like deer, elk, moose and bear, to 165 F. Cook game birds to 180 F for whole birds or 165 F for parts like breasts or thighs.
• Freeze pork safely: Freeze cuts less than 6 inches thick for 20 days at 5 F. Freezing may not kill Trichinella in wild game.
• Don’t rely on salting or smoking: These methods don’t kill Trichinella cysts. Homemade jerky and other preserved meats have caused recent U.S. cases of trichinosis.
• Clean your thermometer: Wash it with soap and water after each use.