title: Evidence of Intercontinental Spread and Uncommon Variants of Low-Pathogenicity Avian Influenza Viruses in Ducks Overwintering in Guatemala.
abstract: Over a hundred species of aquatic birds overwinter in Central America's wetlands, providing opportunities for the transmission of influenza A viruses (IAVs). To date, limited IAV surveillance in Central America hinders our understanding of the evolution and ecology of IAVs in migratory hosts within the Western Hemisphere. To address this gap, we sequenced the genomes of 68 virus isolates obtained from ducks overwintering along Guatemala's Pacific Coast during 2010 to 2013. High genetic diversity was observed, including 9 hemagglutinin (HA) subtypes, 7 neuraminidase (NA) subtypes, and multiple avian IAV lineages that have been detected at low levels (<1%) in North America. An unusually large number of viruses with the rare H14 subtype were identified (n= 14) over two consecutive seasons, the highest number of H14 viruses ever reported in a single location, providing evidence for a possible H14 source population located outside routinely sampled regions of North America. Viruses from Guatemala were positioned within minor clades divergent from the main North American lineage on phylogenies inferred for the H3, H4, N2, N8, PA, NP, and NS segments. A time-scaled phylogeny indicates that a Eurasian virus PA segment introduced into the Americas in the early 2000s disseminated to Guatemala during ~2007.1 to 2010.4 (95% highest posterior density [HPD]). Overall, the diversity detected in Guatemala in overwintering ducks highlights the potential role of Central America in the evolution of diverse IAV lineages in the Americas, including divergent variants rarely detected in the United States, and the importance of increasing IAV surveillance throughout Central America.IMPORTANCERecent outbreaks of highly pathogenic H7N3, H5Nx, and H7N8 avian influenza viruses in North America were introduced by migratory birds, underscoring the importance of understanding how wild birds contribute to the dissemination and evolution of IAVs in nature. At least four of the main IAV duck host species in North America migrate through or overwinter within a narrow strip of Central America, providing opportunities for diverse IAV lineages to mix and exchange gene segments. By obtaining whole-genome sequences of 68 IAV isolates collected from migratory waterfowl in Guatemala (2010 to 2013), the largest data set available from Central America to date, we detected extensive viral diversity, including gene variants rarely found in North America and gene segments of Eurasian origin. Our findings highlight the need for increased IAV surveillance across the geographical span of bird migration flyways, including Neotropical regions that have been vastly undersampled to date.
authors.affiliation: Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala City, Guatemala; Department of Population Health, Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA.
authors.forename: Ana S
authors.initials: AS
authors.lastname: Gonzalez-Reiche
authors.affiliation: Fogarty International Center, National Institutes of Health, Bethesda, Maryland, USA.
authors.forename: Martha I
authors.initials: MI
authors.lastname: Nelson
authors.affiliation: Department of Veterinary Medicine, University of Maryland-College Park, College Park, Maryland, USA.
authors.forename: Mathew
authors.initials: M
authors.lastname: Angel
authors.affiliation: Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala City, Guatemala; Department of Population Health, Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA.
authors.forename: Maria L
authors.initials: ML
authors.lastname: Müller
authors.affiliation: Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala City, Guatemala.
authors.forename: Lucia
authors.initials: L
authors.lastname: Ortiz
authors.affiliation: Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA.
authors.forename: Jayeeta
authors.initials: J
authors.lastname: Dutta
authors.affiliation: Department of Genetics and Genomic Sciences, Icahn School of Medicine at Mount Sinai, New York, New York, USA.
authors.forename: Harm
authors.initials: H
authors.lastname: van Bakel
authors.affiliation: Centro de Estudios en Salud, Universidad del Valle de Guatemala, Guatemala City, Guatemala.
authors.forename: Celia
authors.initials: C
authors.lastname: Cordon-Rosales
authors.affiliation: Department of Population Health, Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, Athens, Georgia, USA; Department of Veterinary Medicine, University of Maryland-College Park, College Park, Maryland, USA.
authors.forename: Daniel R
authors.identifier: 0000-0002-6569-5689
authors.initials: DR
authors.lastname: Perez
keywords: Central America; avian viruses; host range; viral evolution