State lab detects fourth case of bird flu in backyard flock

State officials say that bird flu remains a threat in Oregon, especially to backyard flocks, with confirmation of a fourth infected flock this week.

The state veterinary lab confirmed Wednesday that the virus had sickened a backyard flock in Linn County, the state Agriculture Department said in a release. That’s the second Linn County flock infected and the fourth bird flu case in Oregon this year. The two other instances were in Lane and Polk counties.

All of the cases involved backyard flocks, and state and federal officials have euthanized the birds to prevent further spread. No commercial flocks, which are often raised in enclosed barns, have been infected, the department said.

The infections do not pose a public threat. Infections in people are rare and are associated with close, prolonged and unprotected contact with infected birds or contaminated surfaces. Avian influenza also does not affect the meat or eggs, which remain safe to eat provided they are properly prepared and cooked enough to destroy salmonella or other pathogens.

The owner of the latest infected flock of 40 birds alerted the department by calling its hotline and reporting unusual behavior and dead birds. Infected chickens can develop respiratory problems or diarrhea. It’s often lethal.

The virus is carried by migratory birds. Although the season’s migration is largely over, the virus remains a threat, the department said in an email. With waterfowl still present in the state, Oregon’s Department of Fish and Wildlife continues to find infected wild birds. The Agriculture Department said in an email wild birds likely came into contact with the flock in Linn County.

“In the most recent case, as with the three previous cases, we believe that direct exposure to wild waterfowl was the origin of the infection in the flock,” spokeswoman Andrea Cantu-Schomus said in an email “Normally, we would anticipate that the risk of (bird flu) would subside by the middle of June, but this year’s wet and cool spring has led to waterfowl delaying their migration beyond Oregon, and the extended cool, wet weather has continued to create an environment where the influenza virus is able to more easily transmit between wild birds and poultry.”

State and federal agriculture officials have euthanized 600 birds in backyard flocks since the first cases were discovered in early May.

Agriculture officials say commercial poultry farmers and backyard owners should try to protect their birds by reducing or eliminating contact with wild birds. They also advise owners to call the state about any suspected cases.