Biologists find first cases of infectious bacteria in Southwest Alaska caribou herd

A large bull caribou trots through tundra
A bull caribou from the Mulchatna caribou herd (Photo from USFWS/Togiak Wildlife Refuge)

State biologists have found an unusual disease among caribou in Southwest Alaska. The disease is called brucellosis, caused by the bacteria brucella. It can be lethal to caribou and can lead to miscarriages.

The Department of Fish and Game recently detected cases in the Mulchatna Caribou herd, after spotting a potential case a year ago.

“This was the first time that we were having actual cases in the Mulchatna herd,” Dr. Kimberlee Beckmen, a wildlife veterinarian for Fish and Game, said. “It’s such a low level in caribou throughout Alaska that we don’t pick it up very often. Right now, we know there’s an increase, because more caribou in the herd have brucella or are showing antibodies. ”

A common symptom of brucella in caribou is swelling in the knee, where most of the bacteria is stored. Brucellosis can cause a high fever similar to the flu in people. (Alaska Department of Fish and Game)

Biologists have detected those antibodies during routine sampling. They also found the bacteria in two dead caribou, and have observed swollen knees and enlarged scrotums in others.

A common symptom of brucella in caribou is swelling in the knee, where most of the bacteria is stored. Brucellosis can cause a high fever, similar to the flu. Beckman said people can stay safe by handling raw meat carefully and cooking it properly.

“Freezing doesn’t kill the bacteria,” she said. “Smoking and drying is not extremely effective cause there can be some pathogens and parasites that survive those. So it’s really important to cook the meat to 160 degrees.”

After handling game meat, caribou harvesters should wash hands thoroughly and clean utensils with hot soapy water.

Biologists typically find brucella in caribou herds in the northwestern and central Arctic. There are few samples of brucellosis in Mulchatna herds to determine if the disease is present. Beckman advises those who harvest Mulchatna caribou to report any signs of the disease to the state.