A family gathering resulted in six individuals contracting trichinellosis—commonly referred to as “brain worms”—after consuming undercooked bear meat, according to a report from the U.S. Centers for Disease Control and Prevention (CDC).
Relatives from Arizona, Minnesota, and South Dakota came together in South Dakota for a multi-day visit, during which one family member brought bear meat. This meat had been previously frozen “to kill parasites,” as stated in the report.
The meat was “thawed and grilled with vegetables” as kabobs. The report indicated that it was “initially inadvertently served rare, reportedly because the meat was dark in color, making it difficult for the family members to visually determine its doneness.”
Upon realizing that the meat was not fully cooked, it was “recooked before being served again.”
According to the National Library of Medicine, trichinellosis is a “parasitic infection caused by roundworms…larvae enter the lymphatic circulation and then into the blood, reaching skeletal muscles, myocardium, and brain which are high in oxygen content.”
A week after the meal, a 29-year-old man who had consumed the meat fell ill and was hospitalized twice within a 17-day period. His symptoms included fever, severe myalgias (muscle aches and pains), periorbital edema (swelling around the eyes), and “other laboratory abnormalities,” as reported by the CDC.
During his second hospitalization, he mentioned eating bear meat, leading health authorities to suspect trichinellosis and alert the Minnesota Department of Health.
A positive Trichinella immunoglobulin (Ig) G antibody test confirmed the suspicion, and tests on the bear meat revealed the presence of Trichinella larvae.
Six family members, aged 12 to 62, ended up ill from the meal, although two of those affected “consumed only the vegetables (but no meat).” Two additional family members were hospitalized, but “all six symptomatic persons recovered,” according to the CDC.
While the National Library of Medicine notes that pork is usually the source of trichinellosis infections, the CDC report highlights that “bear meat was the suspected or confirmed source of infection in the majority of outbreaks” in the U.S. since 2016.
The CDC emphasizes that treatment for trichinellosis requires “prompt treatment” with antiparasitic medication to eliminate the adult worms and prevent further larvae release.
The Mayo Clinic advises that the best prevention against trichinellosis is proper food preparation. “Cook pork and meat from wild animals to an internal temperature of 160 F (71 C) at the center,” they recommend. “Use a meat thermometer to ensure the meat is thoroughly cooked.”
