A group of people were struck down with roundworms after eating undercook bear meat at a family reunion.

In July 2022, the Minnesota Department of Health was notified that a 29-year-old man had been to the hospital multiple times over a two-and-a-half-week period with symptoms including fever, severe muscle soreness, swelling around the eyes, among others.

Following his second visit, the man told doctors that he had attended a family gathering in South Dakota, where they ate black bear meat kebabs which had been “harvested” by one of the family members in Saskatchewan, Canada.

The meat had been in a freezer for a month and a half before being thawed out for the meal.

As the meat was dark in colour, it was accidentally served rare initially, before diners noticed and it was recooked, according to the Centres for Disease Control (CDC).

Nine family members, largely from Minnesota but also from South Dakota and Arizona, ate the meal, though some only ate vegetables, which had been cooked and served with the meat.

Doctors ultimately diagnosed the 29-year-old with trichinellosis, a roundworm which is rare in humans and usually contracted by eating wild game.

Once in a human host, the larvae can then move through the body to muscle tissue and organs, including the brain.

Five other family members were diagnosed with the worms, including a 12-year-old girl and two other family members who had only eaten the vegetables.

A total of three family members ended up in hospital, where they were treated with albendazole.

According to the Mayo Clinic, this medication prevents the worms absorbing sugar so they lose energy and die.

The CDC says the only way to ensure trichinella parasites are dead, is to cook the meat to an internal temperature of at least 74C.

It is thought that up to one-quarter of black bears in Canada and Alaska may be infected.