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What is trichinosis?

Trichinosis is a food-borne illness caused by a tiny parasitic worm.

Who gets trichinosis?

Anyone who eats undercooked meat of infected animals is at risk for developing trichinosis.  

How is trichinosis spread?

Animals such as pigs, cats, rats, foxes, wolves and bears can become infected with trichinosis.  The worm spreads to other animals or humans when they eat undercooked or raw infected meat.  In humans, it is most often undercooked infected pork that causes persons to become ill with trichinosis.  Trichinosis does not spread from person-to-person. 

What are the symptoms of trichinosis?

Symptoms range from mild to more severe and can initially include stomach discomfort, nausea, vomiting and diarrhea.  Later, fever, tiredness, headache, cough, aching joints and muscles, and swelling around the eyes may develop. Chest pain can occur if the parasite moves into the diaphragm (the thin muscle separating the lungs from abdominal organs).

How soon after infection do symptoms appear?

Most people do not have symptoms.  If symptoms develop, stomach discomfort usually occurs 1 to 2 days after eating infected raw or undercooked meats. Other symptoms usually develop 8 to 15 days later (range 5 to 45 days).

Can a person get trichinosis again?

A person can get trichinosis again; however, a person who has had an infection in the past does gain some immunity. 

What is the treatment for trichinosis?

Medications including mebendazole and albendazole are used to treat trichinosis. Also, steroid therapy is often given to those with severe symptoms.

What can be done to prevent the spread of trichinosis?

The best prevention is to make sure that pork and wild game meat products are properly cooked to an internal temperature of at least 160┬░ F.  Freezing pork less than 6 inches thick for 20 days at 5┬░ F will kill the parasite larvae; however, this may not be effective in killing larvae found in wild game meats.  Utensils used for processing pork and wild game meat should be thoroughly cleaned before using them for other products.

Boston Public Health Commission
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