Giuseppe
Emeritus
[Source: PLoS ONE, full page: (LINK). Abstract, edited.]
Open Access / Peer-Reviewed / Research Article
Genomic Characterization of H14 Subtype Influenza A Viruses in New World Waterfowl and Experimental Infectivity in Mallards (Anas platyrhynchos)
Andrew M. Ramey, Rebecca L. Poulson, Ana S. Gonz?lez-Reiche, Daniel R. Perez, David E. Stallknecht, Justin D. Brown
Published: May 01, 2014 / DOI: 10.1371/journal.pone.0095620
Abstract
Recent repeated isolation of H14 hemagglutinin subtype influenza A viruses (IAVs) in the New World waterfowl provides evidence to suggest that host and/or geographic ranges for viruses of this subtype may be expanding. In this study, we used genomic analyses to gain inference on the origin and evolution of H14 viruses in New World waterfowl and conducted an experimental challenge study in mallards (Anas platyrhynchos) to evaluate pathogenicity, viral replication, and transmissibility of a representative viral strain in a natural host species. Genomic characterization of H14 subtype IAVs isolated from New World waterfowl, including three isolates sequenced specifically for this study, revealed high nucleotide identity among individual gene segments (e.g. ≥95% shared identity among H14 HA gene segments). In contrast, lower shared identity was observed among internal gene segments. Furthermore, multiple neuraminidase subtypes were observed for H14 IAVs isolated in the New World. Gene segments of H14 viruses isolated after 2010 shared ancestral genetic lineages with IAVs isolated from wild birds throughout North America. Thus, genomic characterization provided evidence for viral evolution in New World waterfowl through genetic drift and genetic shift since purported introduction from Eurasia. In the challenge study, no clinical disease or lesions were observed among mallards experimentally inoculated with A/blue-winged teal/Texas/AI13-1028/2013(H14N5) or exposed via contact with infected birds. Titers of viral shedding for mallards challenged with the H14N5 IAV were highest at two days post-inoculation (DPI); however shedding was detected up to nine DPI using cloacal swabs. The distribution of viral antigen among mallards infected with H14N5 IAV was largely restricted to enterocytes lining the villi in the lower intestinal tract and in the epithelium of the bursa of Fabricius. Characterization of the infectivity of A/blue-winged teal/Texas/AI13-1028/2013(H14N5) in mallards provides support for similarities in viral replication and shedding as compared to previously described waterfowl-adapted, low pathogenic IAV strains in ducks.
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Citation: Ramey AM, Poulson RL, Gonz?lez-Reiche AS, Perez DR, Stallknecht DE, et al. (2014) Genomic Characterization of H14 Subtype Influenza A Viruses in New World Waterfowl and Experimental Infectivity in Mallards (Anas platyrhynchos). PLoS ONE 9(5): e95620. doi:10.1371/journal.pone.0095620
Editor: Srinand Sreevatsan, University of Minnesota, United States of America
Received: February 12, 2014; Accepted: March 28, 2014; Published: May 1, 2014
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
Funding: Funding for this work was provided by the U. S. Geological Survey through the Wildlife Program of the Ecosystem Mission Area and by the National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), and the Department of Health and Human Services under contract HHSN266200700007C. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of this manuscript. The opinions expressed herein are those of the authors and do not necessarily reflect the views of any of the funding agencies.
Competing interests: The authors have declared that no competing interests exist.
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Open Access / Peer-Reviewed / Research Article
Genomic Characterization of H14 Subtype Influenza A Viruses in New World Waterfowl and Experimental Infectivity in Mallards (Anas platyrhynchos)
Andrew M. Ramey, Rebecca L. Poulson, Ana S. Gonz?lez-Reiche, Daniel R. Perez, David E. Stallknecht, Justin D. Brown
Published: May 01, 2014 / DOI: 10.1371/journal.pone.0095620
Abstract
Recent repeated isolation of H14 hemagglutinin subtype influenza A viruses (IAVs) in the New World waterfowl provides evidence to suggest that host and/or geographic ranges for viruses of this subtype may be expanding. In this study, we used genomic analyses to gain inference on the origin and evolution of H14 viruses in New World waterfowl and conducted an experimental challenge study in mallards (Anas platyrhynchos) to evaluate pathogenicity, viral replication, and transmissibility of a representative viral strain in a natural host species. Genomic characterization of H14 subtype IAVs isolated from New World waterfowl, including three isolates sequenced specifically for this study, revealed high nucleotide identity among individual gene segments (e.g. ≥95% shared identity among H14 HA gene segments). In contrast, lower shared identity was observed among internal gene segments. Furthermore, multiple neuraminidase subtypes were observed for H14 IAVs isolated in the New World. Gene segments of H14 viruses isolated after 2010 shared ancestral genetic lineages with IAVs isolated from wild birds throughout North America. Thus, genomic characterization provided evidence for viral evolution in New World waterfowl through genetic drift and genetic shift since purported introduction from Eurasia. In the challenge study, no clinical disease or lesions were observed among mallards experimentally inoculated with A/blue-winged teal/Texas/AI13-1028/2013(H14N5) or exposed via contact with infected birds. Titers of viral shedding for mallards challenged with the H14N5 IAV were highest at two days post-inoculation (DPI); however shedding was detected up to nine DPI using cloacal swabs. The distribution of viral antigen among mallards infected with H14N5 IAV was largely restricted to enterocytes lining the villi in the lower intestinal tract and in the epithelium of the bursa of Fabricius. Characterization of the infectivity of A/blue-winged teal/Texas/AI13-1028/2013(H14N5) in mallards provides support for similarities in viral replication and shedding as compared to previously described waterfowl-adapted, low pathogenic IAV strains in ducks.
_____
Citation: Ramey AM, Poulson RL, Gonz?lez-Reiche AS, Perez DR, Stallknecht DE, et al. (2014) Genomic Characterization of H14 Subtype Influenza A Viruses in New World Waterfowl and Experimental Infectivity in Mallards (Anas platyrhynchos). PLoS ONE 9(5): e95620. doi:10.1371/journal.pone.0095620
Editor: Srinand Sreevatsan, University of Minnesota, United States of America
Received: February 12, 2014; Accepted: March 28, 2014; Published: May 1, 2014
This is an open-access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.
Funding: Funding for this work was provided by the U. S. Geological Survey through the Wildlife Program of the Ecosystem Mission Area and by the National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), and the Department of Health and Human Services under contract HHSN266200700007C. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of this manuscript. The opinions expressed herein are those of the authors and do not necessarily reflect the views of any of the funding agencies.
Competing interests: The authors have declared that no competing interests exist.
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