Three juvenile grizzly bears in Montana tested positive for the highly pathogenic avian influenza (HPAI) virus this fall, according to Montana Fish, Wildlife, and Parks.
The agency said in a news release on Tuesday that the three bears —one near Augusta, one near Dupuyer, and one near Kalispell— were observed to be "in poor condition and exhibited disorientation and partial blindness, among other neurological issues."
The three bears were euthanized due to their sickness and poor condition.
These were the first documented cases of HPAI in grizzly bears. A fox and a skunk in Montana also tested positive for HPAI last year, and the virus has also been found in raccoons, black bears, and even a coyote in other states and countries.
“We suspect these mammals probably get the virus from consuming infected birds,” said FWP Wildlife Veterinarian Jennifer Ramsey.
Bird flu spreading across the country
The Department of Agriculture says the bird flu has turned up in commercial and backyard flocks in 29 states, affecting more than 33 million birds.
Avian influenza(AI) virus is a naturally-occurring virus in birds. AI viruses are classified into two groups based on the severity of the disease they cause in infected poultry. Low pathogenic AI viruses generally cause no clinical illness or only minor symptoms in birds. HPAI viruses are extremely infectious and fatal to poultry and some species of wild birds.
Although the Centers for Disease Control & Prevention considers the risk of HPAI spread to humans to be very low, people are advised to take precautions when handling game birds, sick or dead birds and mammals they find. Whenever possible, avoid contact with sick or dead wildlife. Even if an animal is not suspected to have died from a contagious disease, gloves should always be worn if a dead animal must be handled for disposal.