Avian influenza has been found in a backyard poultry flock in southeast Washington after previously showing up in wild birds in the northwest part of the state, but there is no immediate public health concern, state officials said Friday.

The virus has not been found in commercial in Washington or elsewhere in the United States, state Agriculture Department officials said. They say the virus poses no apparent threat to humans but highly pathogenic strains can be deadly to domestic poultry and sometimes to wild birds.

Avian influenza does not affect poultry meat or egg products, which remain safe to eat, the agency said.

Officials say the owner of the flock of about 150 birds near Benton City contacted the Agriculture Department after losing nearly 50 birds in the past week.

The state Agriculture Department says it has activated a multi-agency response and will work closely with U.S. Department of Agriculture officials.

The highly pathogenic H5 confirmed in the flock is similar to the virus found in a Washington captive gyrfalcon last month, although additional testing is being conducted to identify the strain. The falcon had been fed wild birds killed by hunters. A separate strain of the H5 virus was found in a wild duck. Both viruses have been found in other parts of the world and have not caused any human infection to date, the USDA has said.

Canadian officials say an outbreak in British Columbia has spread to more than a half dozen poultry farms and affected about 245,000 birds.

The Benton County backyard flock includes domestic waterfowl with access to the outdoors.

"We have not diagnosed the virus anywhere else in our domestic poultry population, but the presence of the virus in migratory waterfowl is a risk to backyard poultry," state veterinarian Dr. Joe Baker said Friday in a statement. "One step owners should take is preventing contact between their birds and ."

Also last month, federal agricultural officials confirmed the presence of a strain of the H5 virus in guinea fowl and chickens in a 100-bird backyard poultry flock in the southern Oregon community of Winston.