Six family members were sickened with a rare parasitic disease caused by roundworm larvae after they ate kebabs made of bear meat.

According to NBC News report published this week by the Centers for Disease Control and Prevention revealed new details of the outbreak, which occurred in July 2022 at a nine-person family reunion in South Dakota.

One family member brought meat to the reunion from a black bear hunted in northern Canada. The meat had been frozen in a household freezer for 45 days. Hunting black bears is legal in Canada and many U.S. states.

The family made kebabs with the thawed meat, alongside grilled vegetables. According to the CDC, the family had a hard time determining whether the kebabs were fully cooked, because the meat was dark in color. So it was unintentionally served and eaten rare.

A week later, one family member — a 29-year-old man in Minnesota — developed a fever, severe muscle pain and swelling around the eyes. He was hospitalized twice for his symptoms.

The man tested positive for antibodies to Trichinella, a type of roundworm. Five other family members also developed symptoms such as fevers, headache, stomach pain, diarrhea, muscle pain and swelling around the eyes.

Two others who’d been exposed did not develop symptoms, and the CDC could not confirm whether the ninth person had been exposed to Trichinella.

The CDC tested the remaining frozen meat and detected larvae from the same roundworm species.

The agency presumed that all six family members had trichinellosis, a disease caused by eating undercooked meat contaminated with Trichinella larvae.

Such infections are rare. From January 2016 to December 2022, the CDC identified seven trichinellosis outbreaks in the U.S. involving 35 probable or confirmed cases. Most were linked to bear meat.

Trichinellosis is not the same parasitic infection that presidential candidate Robert F. Kennedy Jr. recently revealed he once suffered from. Kennedy said the brain infection he got comes from pork tapeworm larvae.

Two of the infected people at the family reunion ate the vegetables without the meat, the CDC said. Trichinella-infected meat can result in cross-contamination, so meat and its juices should be separated from other foods during cooking.

Three of the family members were hospitalized, each of whom had consumed the bear meat. They received a treatment called albendazole, which kills parasitic worms and their larvae.

All six people recovered from the disease.

The CDC report warns that freezing meat won’t kill all species of Trichinella. The bear meat at the family reunion, for instance, was contaminated with a species found in Arctic bears that’s resistant to freezing.

“Persons who consume meat from wild game animals should be aware that that adequate cooking is the only reliable way to kill Trichinella parasites,” the report’s authors wrote.

The CDC recommends cooking wild game meat to an internal temperature of at least 165 degrees Fahrenheit, which should be verified with a meat thermometer — not by looking at the color of the meat.

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