The Nunavut Department of Health issued a public health advisory Tuesday for residents of Clyde River as polar bear meat distributed in the community in early October may have Trichinella.

Polar bear/U.S. Geological Survey
Polar bear/U.S. Geological Survey

They advise residents to thoroughly cook the meat as freezing or fermenting does not kill the parasite. In addition, they say to the public to not feed infected meat to animals as they can also get sick.

In the Arctic, trichinellosis, or trichinosis, is caused by a microscopic parasite called Trichinella nativa, sometimes found in the meat of wild mammals like polar bears, black bears, wolves, foxes and, most commonly, walruses.

Trichinosis is a parasitic disease caused most commonly by the roundworm Trichinella spiralis. If someone ingests undercooked or raw meat with the encysted larvae, the stomach acid releases the larvae which mature to adults in the intestine.

After about a week the female starts releasing larvae which enter the bloodstream and find their way to skeletal muscle where they encapsulate.

There can be gastrointestinal symptoms mimicking acute food poisoning when there is activity of the adults in the intestine.

Trichinella spiralis parasite
Trichinella spiralis cysts

Sudden appearance of fever, muscle soreness and pain with swelling of parts of the face is early classic signs. This can sometimes be followed by retinal hemorrhages and other ocular signs.

With heavy infections cardiac, respiratory and neurological problems may ensue with death by heart failure being most common. The more larvae you ingest, the more serious the disease.

Due to inspections, laws that prohibit feeding meat and meat by products to swine, better pest control by keeping rats away from where pigs are kept and an educated public who is aware of the risks of eating undercooked pork, trichinosis is a minor public health problem.

There are still small outbreaks from time to time here and abroad with the consumption of dog, bear, wild boar and cougar, just to name a few.

Other animals that are considered hosts to this parasite include: cats, rats, horses, foxes, wolves, polar bears, marine mammals of the Arctic and lions and leopards in the tropics.

What preventive measures are available?

• Cook all fresh pork, pork products and meat from wild animals to where all the meats reaches 160° F. The meat should turn from pink to gray.
• Freezing pork at -13° F for at least 10 days will kill the cysts. The exception to this rule is strains of Trichinella found in walrus and bear meat which are cold-resistant and must be cooked as noted above.
• Smoking, salting or drying meat is not effective.