(Wallowa County, OR) -- The U.S. Department of Agriculture has confirmed a case of highly pathogenic avian influenza in a backyard flock of ducks and chickens in Wallowa County. It's the first confirmed case in the county, with initial testing done at Oregon State University before being verified by the USDA. State veterinarians have quarantined the property and euthanized the birds to prevent further spread. Officials say no affected animals entered the food supply, and properly cooked poultry and eggs remain safe to eat. The Oregon Department of Agriculture is urging flock owners to strengthen biosecurity as wild bird migration increases the risk of infection.