Abstract Title
Genetic characterization of influenza A viruses in wild waterfowl in Argentina reveals unique reassortment patterns and novel genotypes.
Abstract
This study investigates the pre-emergence landscape of Influenza A Virus (IAV) in Argentinian wild birds, prior to the introduction of high-pathogenicity H5N1 into the country for the first time in February 2023.
By analyzing 2496 bird samples collected from 2017-2019, we identified forty-four IAV sequences from nine duck species, including a previously unreported host in the region, the ringed teal (Callonetta leucophrys). Notably, we confirmed the circulation of five novel IAV subtypes in Argentinian wild birds: H2N1, H3N8, H7N3, H8N4, and H11N9. Furthermore, we discovered a new South American H8 lineage, which diverged from the North American (NAm) lineage over 48 years ago.
Phylogenetic analyses of full-genome IAVs revealed that Argentinian viruses possess internal gene segments exclusively from the SAm lineage, while exhibiting frequent reassortment of hemagglutinin (HA) and neuraminidase (NA) glycoproteins between SAm and NAm lineages. This unique reassortment pattern has generated novel genotypes not observed elsewhere, raising concerns that future reassortment with H5N1 could create highly pathogenic avian influenza viruses (HPAIV) with unforeseen characteristics. This comprehensive characterization of pre-existing IAV diversity paves the way for informed monitoring and preparedness efforts against potential HPAIV emergence in Argentina, moreover considering that H5N1 viruses from avian and marine mammal clades have been circulating in the country between February 2023 to February 2024.
By analyzing 2496 bird samples collected from 2017-2019, we identified forty-four IAV sequences from nine duck species, including a previously unreported host in the region, the ringed teal (Callonetta leucophrys). Notably, we confirmed the circulation of five novel IAV subtypes in Argentinian wild birds: H2N1, H3N8, H7N3, H8N4, and H11N9. Furthermore, we discovered a new South American H8 lineage, which diverged from the North American (NAm) lineage over 48 years ago.
Phylogenetic analyses of full-genome IAVs revealed that Argentinian viruses possess internal gene segments exclusively from the SAm lineage, while exhibiting frequent reassortment of hemagglutinin (HA) and neuraminidase (NA) glycoproteins between SAm and NAm lineages. This unique reassortment pattern has generated novel genotypes not observed elsewhere, raising concerns that future reassortment with H5N1 could create highly pathogenic avian influenza viruses (HPAIV) with unforeseen characteristics. This comprehensive characterization of pre-existing IAV diversity paves the way for informed monitoring and preparedness efforts against potential HPAIV emergence in Argentina, moreover considering that H5N1 viruses from avian and marine mammal clades have been circulating in the country between February 2023 to February 2024.
Co-Author(s)
Lily Kreps1, Lucia Ortiz Batsche2, Valeria S. Olivera3, Lucas Ferreri2, Martha I. Nelson1, Daniel R. Perez2, Agustina Rimondi3,4
1 National Center for Biotechnology Information, National Library of Medicine, National Institutes of Health, Bethesda, USA
2 Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, Athens, USA
3 Instituto de Virología e Innovaciones Tecnológicas, INTA-CONICET, Buenos Aires, Argentina
4 Robert Koch Institute Unit 17, Berlin, Germany
Abstract Category
Notable outbreaks, field and molecular epidemiology, and surveillance in wild birds