Skip to main content
U.S. flag

An official website of the United States government

Widespread detection of highly pathogenic H5 influenza viruses in wild birds from the Pacific Flyway of the United States

July 7, 2016

A novel highly pathogenic avian influenza virus belonging to the H5 clade 2.3.4.4 variant viruses was detected in North America in late 2014. Motivated by the identification of these viruses in domestic poultry in Canada, an intensive study was initiated to conduct highly pathogenic avian influenza surveillance in wild birds in the Pacific Flyway of the United States. A total of 4,729 hunter-harvested wild birds were sampled and highly pathogenic avian influenza virus was detected in 1.3% (n = 63). Three H5 clade 2.3.4.4 subtypes were isolated from wild birds, H5N2, H5N8, and H5N1, representing the wholly Eurasian lineage H5N8 and two novel reassortant viruses. Testing of 150 additional wild birds during avian morbidity and mortality investigations in Washington yielded 10 (6.7%) additional highly pathogenic avian influenza isolates (H5N8 = 3 and H5N2 = 7). The geographically widespread detection of these viruses in apparently healthy wild waterfowl suggest that the H5 clade 2.3.4.4 variant viruses may behave similarly in this taxonomic group whereby many waterfowl species are susceptible to infection but do not demonstrate obvious clinical disease. Despite these findings in wild waterfowl, mortality has been documented for some wild bird species and losses in US domestic poultry during the first half of 2015 were unprecedented.

Publication Year 2016
Title Widespread detection of highly pathogenic H5 influenza viruses in wild birds from the Pacific Flyway of the United States
DOI 10.1038/srep28980
Authors S.N. Bevins, Robert J. Dusek, C. LeAnn White, Thomas Gidlewski, B. Bodenstein, Kristin G. Mansfield, Paul DeBruyn, Donald K. Kraege, E. L. Rowan, Colin Gillin, B. Thomas, S. Chandler, J. Baroch, B. Schmit, M. J. Grady, R. S. Miller, M.L. Drew, S. Stopak, B. Zscheile, J. Bennett, J. Sengl, Caroline Brady, Hon S. Ip, Erica Spackman, M. L. Killian, Mia Kim Torchetti, Jonathan M. Sleeman, T.J. DeLiberto
Publication Type Article
Publication Subtype Journal Article
Series Title Scientific Reports
Index ID 70174284
Record Source USGS Publications Warehouse
USGS Organization National Wildlife Health Center
Was this page helpful?