High Pathogenic Avian Influenza (H5N1) Discovered in a Polar Bear in far northern Alaska

Just published in Emerging Infectious Diseases, (https://wwwnc.cdc.gov/eid/article/30/8/24-0481_article), community members in Point Barrow, Alaska, the northernmost tip of the United States, found a dead polar bear in August 2023. Brain tissue from this young male bear then tested positive for the highly pathogenic avian influenza (HPAI) virus genotype A3, a Eurasian strain of the avian influenza virus, documenting the first case of HPAI in a polar bear. In August of 2023, dead Short-tailed Shearwaters (Ardenna tenuirostris) near Point Barrow also tested positive for HPAI H5N1 and a small mortality event in other Alaskan seabirds nearby, this time in Common Murres (Uria aalge), was also documented due to avian influenza. It is suspected that the bear may have become infected with HPAI through ingestion of a positive bird. The USDA’s Wild Bird Avian Influenza Surveillance dashboard is a great way to keep track of the distribution of HPAI H5N1 across the USA and can be found here: https://www.aphis.usda.gov/livestock-poultry-disease/avian/avian-influenza/wild-bird-surveillance-dashboard.