Bird Flu Outbreak Hits Oregon; wildlife officials say it’s “definitely serious”

An outbreak of highly pathogenic avian influenza in wild birds and backyard flocks has killed thousands of birds statewide, Oregon Wildlife and Agriculture officials say.

The disease, commonly known as bird flu, has been detected in nearly every county in Oregon. Its current strain is particularly deadly to wild birds, which are dying in greater numbers than during previous outbreaks.

The number of backyard flocks – which include chickens, ducks and other domesticated birds – that have been affected is also much higher than in recent outbreaks. Although turkeys are particularly susceptible to the disease, only a few have died locally because Oregon is not a turkey-producing state, officials said.

Sick birds behave as if they are drunk. They are uncoordinated and lethargic; they shake, swim in circles and fly into the sides of houses. Those who show symptoms usually die within 72 hours.

“It’s definitely serious,” said Ryan Scholz, state veterinarian with the Oregon Department of Agriculture.

Bird flu viruses occur naturally in the environment, and bird flu does not always cause mortality or even illness in birds. Some birds, such as mallards, have developed immunity to the disease, even to its highly pathogenic species. They do not suffer from symptoms, but they transmit the disease, most often through feces.

The virus usually arrives in the US from Europe or Eurasia, carried by waterfowl that fly thousands of miles. Birds spread the disease every time they land to rest.

Deadlier strains of bird flu have been on the rise in recent years. Highly pathogenic avian influenza has devastated wild birds and the poultry industry worldwide. The virus is now endemic in Europe and Asia.

This year could prove to be even more deadly than usual. The virus usually disappears with dry and hot weather, as low-pathogenic strains of the disease naturally outcompete it. This happened in 2014-15, the last major outbreak in the US in domestic birds.

But birds haven’t stopped improving this summer in the Pacific Northwest. They continued to die during the warmest months and deep into autumn – an anomaly in the way the virus usually works.

Wild birds have been sickening and dying in recent weeks from Fernhill Wetlands in Forest Grove to the Tualatin River Wildlife Refuge to the Willamette Valley Wildlife Refuge. It’s impossible to know exactly how many wild birds are affected, said Colin Gillin, state wildlife veterinarian.

“To say it was in the thousands would be an understatement,” Gillin said.

About 17 percent of the waterfowl that were tested registered positive for the disease, a “significant number,” Gillin said. Currently, the species most affected are the racket geese, but the disease also kills numerous golden eagles, hawks, owls and herons.

Songbirds and wild turkeys were not affected, Gillin said, because they typically do not interact with waterfowl and are not scavengers.

There is also concern for snow geese after nearly 400 sick or dead geese were found in Wiser Lake in western Washington state a few days ago and several tested positive for bird flu. Many of the dead birds were snow geese. Those birds are just starting to arrive in Oregon, so many more could die in the coming weeks in our state, Gillin said.

In other states, avian influenza has also been detected in mammals such as skunks, foxes and coyotes — usually in younger animals.

The disease does not pose a great risk to humans, although some are infected with avian influenza viruses. Still, it’s a mutating disease, officials said, so hunters should wear protective gear like masks and gloves to handle wild birds safely, and should change clothes when they get home. Hunters should not kill birds that look sick. They should also minimize dog interaction with waterfowl.

Some hunters worry whether the die-off will affect the duck and goose hunting seasons, which are now open.

“I’m seeing a lot of dead geese on Sauvie Island and also a lot of sick ones,” local hunter Eric Strand said via email.

But Brandon Reishus, Oregon’s migratory bird coordinator, said it’s too early to predict. “We have no plans to close the hunt. But it’s an evolving situation.”

The Oregon Department of Agriculture said 16 cases have been confirmed this year in smaller flocks of domesticated birds. That’s a significant increase from the two confirmed cases in the 2014-2015 outbreak, said Scholz, the Department of Agriculture veterinarian. More flocks are being tested after a spike in calls over the past week.

About two thousand domestic birds have been euthanized or died from bird flu in Oregon this year in reported cases, Scholz said. Some backyard flock owners use only the birds or their eggs for home consumption, while others have hundreds of birds and sell their products to the public. The state imposed several bird flu quarantine this summer and fall to prevent the sale of meat or eggs from virus-affected areas.

There were no reported cases in commercial farms – farms with much larger herds that are often raised in large barns — probably because they have strict biosecurity measures, Scholz said.

The size of the affected flocks varied from 4 to 500 individuals. The larger the flocks, the more birds die quickly – so the risk of disease for larger farms is significant. In the case of one large backyard farm with about 400 chickens, Scholz said, the birds started dying on Saturday and by Monday there were “barrels of dead birds.” Agricultural officials had to euthanize the rest.

And it’s not just a chicken problem. In addition to hundreds of dead chickens, the epidemic took away domestic ducks, quails, pheasants, and even a few emus this year.

With cooler weather and wild bird migration peaking in the coming weeks, the environment is primed for transmission, Scholz said.

“Weather like this … it’s the making of a perfect storm,” he said.

Wildlife officials say it’s okay to put one to two dead wild birds in two bags and throw them in the trash. People can also bury birds shallowly or simply leave them where they are in the wild. Officials said people should be careful when handling the birds and should never transport them.

As for domestic birds, responsible owners can prevent exposure of their flocks to wild waterfowl by fencing off access to ponds or grass fields, Scholz said.

Owners of domestic flocks should call the Department of Agriculture if more than one bird in their flock dies quickly, officials said. Reported cases are examined by a veterinarian and samples are collected for testing. If the disease is confirmed, all the birds are euthanized, Scholz said.

“Bird flu is 100 percent fatal” for domestic birds, which haven’t developed the immunity that some wild birds have, he added. “All the birds will die of disease. We would rather humanely euthanize them than wait for them to get sick and die.”

– Gosia Wozniacki; [email protected]; @gosiawozniacka

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