A moose acting aggressively in a Northwest Alaska community tested positive for rabies this month, marking the first rabid moose case detected in the state — and North America overall.
The case has prompted Alaska officials to increase rabies surveillance across a large swath of the state.
Alaska Department of Fish and Game staff based in the Nome area received several reports June 2 describing a moose in the community of Teller — about 70 miles northwest of Nome — with bare patches of skin that was behaving strangely and acting aggressively toward people, the department said in a statement.
“It was drooling and being very aggressive towards people and it was wobbly, unstable on its legs,” said Kimberlee Beckmen, a wildlife veterinarian with the Alaska Department of Fish and Game. “That was very unusual behavior.”
Fish and Game staff, after consulting with Beckmen, killed the moose that afternoon because of its aggressive behavior and signs indicative of a rabies infection. The carcass was burned to make sure the virus didn’t spread to any scavengers, Beckmen said.
Three days later, on June 5, the Alaska State Virology Laboratory detected the rabies virus in the moose’s brain, Fish and Game said in its statement.
While Fish and Game initially said last Wednesday that moose in South Dakota, Minnesota and Canada have also been diagnosed with rabies, the department corrected its statement Monday to reflect that the only known cases of rabies in moose have been reported in Europe.
Beckmen said that those locations in North America were places where moose were tested for rabies — but the results were negative.
Alaska’s moose rabies case is “actually the first case in North America,” she said, “back to the national database records from the 1950s.”
The moose most likely contracted rabies from a fox, according to Fish and Game. Beckman said the moose had a wound from a fox bite. The federal Centers for Disease Control and Prevention confirmed that the moose had contracted the Arctic fox rabies variant, which circulated this winter among red foxes on the Seward Peninsula and Arctic foxes on the North Slope.
While many mammals are susceptible to rabies, including river otters, lynx, bats, caribou and reindeer, the rabies virus in Alaska is most commonly found in red and Arctic foxes. Rabies outbreaks happen among fox populations on the northern coast and in Southwest and Northwest Alaska every year, with larger outbreaks every eight to 10 years, Beckmen said.
“Last winter was our largest outbreak that we detected,” Beckmen said. “There was a very large number of red foxes in the Nome area that were rabid — 29% of the foxes sampled were.”
The outbreak among foxes meant higher exposure to rabies for dogs that were getting in fights with rabid foxes, Beckmen said.
The virus can also infect — and be fatal for — humans. According to the CDC, only one to three human rabies cases are reported annually in the United States.
Previously in Alaska, the only moose that were screened for rabies were those showing neurologic signs, but after this new case, Fish and Game plans to test all dead or euthanized wild mammals from parts of the state where rabies is generally always present at a certain level among foxes, Beckmen said. That includes coastal areas spanning northern, northwestern and western parts of Alaska, and the Alaska Peninsula.
“We’re going to increase our rabies surveillance because of this,” Beckmen said.
Fish and Game said in its statement that since moose are largely solitary animals, “it is very unlikely that any rabies outbreak will occur in the moose population, but isolated cases such as this one occur rarely.”
People who find a dead mammal or see a mammal with any signs of rabies — such as excessive salivation, aggressive behavior or bite marks — can contact Fish and Game by calling 907-328-8354. Vaccinating pets against the virus is also an important way to prevent the spread of rabies.
Wildlife officials encouraged hunters and those processing game meat to use precautions like wearing gloves while butchering moose or other mammals, washing hands thoroughly after handling game, disinfecting knives and other equipment that came into contact with the meat, and cooking game thoroughly to an internal temperature of 165 degrees Fahrenheit.