Last month we saw outbreaks HPAI H5N2 in British Columbian poultry farms (see Fraser Valley B.C. Culling Poultry After Detecting H5 Avian Flu) followed by the detection of HPAI H5N2 and HPAI H5N8 in wild and migratory birds in both Washington State and Oregon (see USDA/APHIS: H5N8 Detected In Oregon Backyard Flock).
Given the recent detections of HPAI H5 in Canada, and the Pacific Northwest of the United States – and the migratory patterns of birds along the Pacific Flyway – one shouldn’t be terribly surprised to see additional detections further south over time.
While I haven’t found anything on the APHIS, USDA, or California Department of Agriculture websites, the non-profit organization California Waterfowl has posted the following short notice (h/t Gert van der Hoek on FluTrackers) on their Facebook page, indicating that a hunter-harvested duck in Butte California has tested positive of HPAI H5.
Avian influenza news from the USDA: This week, as a result of increased surveillance in the Pacific flyway, USDA has confirmed the presence of HPAI in a wild duck in Butte County, California.
The samples in California were collected from a hunter-harvested gadwall in Butte County, California, as part of increased wild bird surveillance. Testing by the California Animal Health and Food Safety Laboratory, a National Animal Health Laboratory Network (NAHLN) laboratory, was positive on H5 PCR, and the sequencing results were consistent with Eurasian H5N8. The National Veterinary Services Laboratories (NVSL) received the samples on December 31 and confirmed the presence of HPAI H5N8. This is the same HPAI H5N8 strain that was found in Washington gryfalcons and the Oregon backyard poultry flock. This is not an unexpected finding, given wild waterfowl migratory patterns in the Pacific flyway.
Although this seems pretty solid, I’ll keep an eye out for any additional information. Hopefully we’ll get an OIE notification or some other official statement that would confirm this report.