WINSTON, Ore. – Oregon activated a multi-agency response plan following the discovery of highly pathogenic H5N8 avian influenza in a flock of domestic birds in Winston, Ore., in Douglas County.On Dec. 20, South Korea imposed a ban of poultry imports from the United States following news of the outbreak. The ban includes live birds, eggs and poultry products that have not been heated to 70°C within the past 21 days, the Ministry of Food, Agriculture, Forestry and Fisheries said in a statement.The US Department of Agriculture confirmed the presence of the virus in a backyard poultry flock of guinea fowl and chickens. The flock of about 100 birds had access to the outdoors, according to the Oregon Department of Agriculture (ODA), and migratory birds frequented a nearby pond and marsh on the premises.“Steps are being taken to contain the disease and we have not diagnosed avian influenza elsewhere in Oregon’s domestic poultry population, but the presence of the virus in migratory waterfowl poses a potential risk to our backyard poultry,” said Dr. Brad LeaMaster, ODA’s state veterinarian. “This event underscores the importance of biosecurity for backyard bird owners. We strongly encourage owners to take biosecurity measures to reduce the risk of spreading the disease. That includes preventing contact between their birds and wild birds. We also want them to monitor their flock closely and report sick birds.”To date, no avian flu virus has been found in commercial poultry anywhere in the United States. ODA is advising commercial poultry growers and backyard flock owners to practice biosecurity measures and to be vigilant in the wake of the latest discovery.