The U.S. reported its first documented outbreak of H5N9 avian influenza on a poultry farm, according to the World Organisation for Animal Health (WOAH).

Highly pathogenic avian influenza (HPAI) has spread globally in recent years, necessitating the culling of millions of poultry. While H5N1 has been the predominant strain responsible for significant outbreaks, H5N9 remains less common.