The veterinary authority, APHIS, sent Follow Up Report No.1 to the World Organisation for Animal Health (OIE) on 7 January.

The report outlines one outbreak of highly pathogenic avian influenza (H5N2) in a backyard poultry flock in Benton County in Washington state.

The affected premises is a small backyard mixed free-range flock of geese, turkeys, chickens, ducks, and pigeons that are allowed access to the outdoors and regularly exposed to wild migratory waterfowl. A total of 37 birds died and the rest of the flock of 178 were destroyed.

The report adds that USDA Animal and Plant Health Inspection Service (APHIS), in conjunction with State Departments of Agriculture and Wildlife, are continuing to conduct a comprehensive epidemiological investigation and enhanced surveillance in response to the HPAI H5N2 wild bird related event.

The USDA APHIS National Veterinary Services Laboratory (NVSL) has confirmed avian influenza virus H5N2 in a backyard mixed flock. Preliminary results indicate that the H5N2 identified is 99 per cent similar to the recent H5N2 isolated from the Northern pintail duck.

Following the epidemiological investigation of backyard AIV infected premises, as of 6 January 2015, two high-risk epidemiologically-linked contact backyard premises have been identified and placed under quarantine. Biological sampling for the AI virus has been completed and results are pending.

Enhanced surveillance has been implemented within a 10-km radius of the farm.

The report adds that the HPAI H5N2 virus has not been found in commercial poultry anywhere in the United States.

In Follow Up Report No.3, also dated 7 January, no new outbreaks of H5N8 highly pathogenic avian influenza have been reported.