Serological #Evidence of Exposure to Eurasian-Lineage HPAI #H5N1 Clade 2.3.4.4b in Wild #Mammals in #Ohio, #USA, 2024–2025
Abstract The Goose/Guandong lineage of highly pathogenic avian influenza virus [A/Goose/Guangdong/1/1996(H5N1)] is the progenitor of the currently circulating Eurasian-lineage highly pathogenic avian influenza H5N1 clade 2.3.4.4b and has been the most consequential highly pathogenic avian influenza lineage globally. Despite increased reports of infections, the extent of exposure and role of wild mammals in the ecology and transmission dynamics of the virus remains poorly understood. We surveyed wild mammals in Ohio, United States to investigate the potential spillover of highly pathogenic H5N1 avian influenza clade 2.3.4.4b. While no active infections —defined as positive results indicative of viral replication and potential propagation—were detected by swab-based molecular tests, serological assays revealed antibodies against multiple avian influenza virus antigens in raccoons and opossums . Specifically, antibodies to avian influenza virus nucleoprotein were detected in 54.9% (...