Rare bear meat at gathering gives 10 people a scare—and parasitic worms

If you're going to eat a bear, make sure it's not rare. You'd be forgiven for thinking that once the beast has been subdued, all danger has passed. But you might still be in for a scare. The animal's flesh can be riddled with encased worm larvae, which, upon being eaten, will gladly reproduce in your innards and let their offspring roam the rest of your person, including invading your brain and heart. To defeat these savage squirmers, all one must do is cook the meat to at least 165° Fahrenheit. But that simple solution continues to be ignored, according to a report today in the Centers for Disease Control and Prevention's Morbidity and Mortality Weekly Report. In this week's issue, health officials in North Carolina report that rare bear meat was served at a November 23 gathering, where at least 22 people ate the meat and at least 10 developed symptoms of a worm infection. Of the 10, six were kids and teens between the ages of 10 and 18. The infection is from the roundworm Trichinella, which causes trichinellosis. While the infection is rarely fatal, the nematodes tend to burrow out of the bowels and meander through the body, embedding in whatever muscle tissue they come across. A telltale sign of an infection in people is facial swelling, caused when the larvae take harbor in the muscles of the face and around the eyes. Of the 10 ill people in North Carolina, nine had facial swelling. Local health officials were onto the outbreak when one person developed flu-like symptoms and puzzling facial swelling. They then traced it back to the gathering. The report doesn't specify what kind of gathering it was but noted that 34 attendees in total were surveyed, from which they found the 22 people who ate the rare meat. The 10 people found with symptoms are technically considered only "probable" cases because the infections were never diagnostically confirmed. To confirm a trichinellosis infection, researchers need blood samples taken after the person recovers to look for antibodies against the parasite. None of the 10 people returned for blood draws.

Challenges

Health investigators also ran into problems when trying to stamp out the infections. All 10 people were prescribed an anti-parasitic drug (albendazole), which is effective against the infection. But some people apparently delayed getting treatment because the prescription was around $100. "Challenges associated with diagnosis and treatment of trichinellosis serve as a reminder for local health departments and wildlife management to communicate safe wild game meat preparation," the authors conclude. Trichinellosis used to be associated with eating undercooked pork. The worms can live in many types of animals, including rodents, but pastured pigs would pick up infections through their cannibalistic and scavenging tendencies. Fortunately, pork-related cases are nearly non-existent in the US now thanks to improvements to pig-raising practices. The remaining source of infection in humans is wild game, including bear, but also boar and moose. The North Carolina officials noted that "thousands" of bears are harvested in the state each year. They suggest that surveying wild game for Trichinella infections might be a good idea. Earlier this year, health officials from multiple states reported that six family members developed trichinellosis after serving undercooked bear kabobs at a family gathering. In that case, the bear had been harvested in Canada. But investigators highlighted another troubling twist with these worms: Trichinella can be freeze-resistant. The bear meat that sickened the family had in fact been frozen for nearly four months. Yet motile, living larvae remained after the meat was thawed, and two family members became infected after eating only vegetables that were cooked alongside the meat.