Migratory waterfowl are spreading bird flu in Washington, according to the Washington Department of Agriculture.

Bird flu has been confirmed in small backyard flocks in Lewis County — which is Pacific County’s next-door neighbor to the east — and in a commercial poultry farm in Clackamas County, Ore., as well as in a backyard flock in Crook County, Ore.

Migratory waterfowl are spreading the virus, according to the Washington State Department of Agriculture. “Every backyard flock is at risk right now,” State Veterinarian Amber Itle said in a statement.

The virus was previously detected at a commercial poultry farm Oct. 15 in Franklin County and a 60-bird backyard flock Oct. 17 in Kitsap County. The outbreak at the commercial operation affected 839,700 chickens. Bird flu has been found in 48 flocks in Washington since 2022. The virus has been detected in 18 of the state’s 39 counties.

Bird flu was identified in a small flock of chickens in Pacific County in May 2022, among the first in the state. Cases haven’t been reported in the county since then.

The Centers for Disease Control and Prevention confirmed two workers at the Franklin County farm contracted avian influenza, the state Health Department said in an Oct. 24 press release.

Two other workers tested positive. Tests to confirm the preliminary diagnosis are pending, according to the department.

Washington is the only state with three outbreaks in the past 30 days, according to USDA. Idaho has had two outbreaks, both in backyard flocks.

The current outbreak of avian influenza in the U.S. began in February 2022. The virus has been detected in 48 states, infecting 512 commercial farms and 670 backyard flocks, and claiming 104.26 million domestic birds.

Bird flu at the commercial farm in Clackamas County resulted in about 150,000 birds being euthanized, according to the Oregon Department of Agriculture. It was first case of bird flu in Oregon since March.

Single cases have been found in commercial poultry farms in California and Utah. The Utah outbreak affected 1.8 million birds, according to USDA.

Bird flu has infected dairy cattle in 14 states, including Idaho and California.

The Washington Department of Agriculture asked birds owners to report unusual illnesses or mortalities by calling 1-800-606-3056.

Since 2022, three commercial poultry flocks and 37 backyard flocks have been affected in Oregon, according to the state Department of Agriculture.