title: Adaptive Heterosubtypic Immunity to Low Pathogenic Avian Influenza Viruses in Experimentally Infected Mallards.
abstract: Mallards are widely recognized as reservoirs for Influenza A viruses (IAV); however, host factors that might prompt seasonality and trends in subtype diversity of IAV such as adaptive heterosubtypic immunity (HSI) are not well understood. To investigate this, we inoculated mallards with a prevailing H3N8 low pathogenic avian influenza virus (LPAIV) subtype in waterfowl to determine if prior infection with this virus would be protective against heterosubtypic infections with the H4N6, H10N7 and H14N5 LPAIV subtypes after one, two and three months, respectively. Also, we investigated the effect of cumulative immunity after sequential inoculation of mallards with these viruses in one-month intervals. Humoral immunity was assessed by microneutralization assays using a subset of representative LPAIV subtypes as antigens. Our results indicate that prior inoculation with the H3N8 virus confers partial protective immunity against subsequent heterosubtypic infections with the robustness of HSI related to the phylogenetic similarity of the HA protein of the strains used. Furthermore, induced HSI was boosted and followed by repeated exposure to more than one LPAIV subtype. Our findings provide further information on the contributions of HSI and its role in the dynamics of IAV subtype diversity in mallards.
authors.affiliation: Poultry Diagnostic and Research Center, The University of Georgia, Athens, Georgia, United States of America.
authors.forename: Karen M
authors.initials: KM
authors.lastname: Segovia
authors.affiliation: Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, Georgia, United States of America.
authors.forename: David E
authors.initials: DE
authors.lastname: Stallknecht
authors.affiliation: Southeast Poultry Research Laboratory, Agricultural Research Service, U.S. Department of Agriculture, Athens, Georgia, United States of America.
authors.forename: Darrell R
authors.initials: DR
authors.lastname: Kapczynski
authors.affiliation: Poultry Diagnostic and Research Center, The University of Georgia, Athens, Georgia, United States of America.
authors.forename: Lisa
authors.initials: L
authors.lastname: Stabler
authors.affiliation: Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, Georgia, United States of America.
authors.forename: Roy D
authors.initials: RD
authors.lastname: Berghaus
authors.affiliation: Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, Georgia, United States of America.
authors.forename: Alinde
authors.initials: A
authors.lastname: Fotjik
authors.affiliation: Southeastern Cooperative Wildlife Disease Study, Department of Population Health, College of Veterinary Medicine, University of Georgia, Athens, Georgia, United States of America.
authors.forename: Neus
authors.initials: N
authors.lastname: Latorre-Margalef
authors.affiliation: Poultry Diagnostic and Research Center, The University of Georgia, Athens, Georgia, United States of America.
authors.forename: Monique S
authors.initials: MS
authors.lastname: França
mesh_terms: D000222:Adaptation, Physiological / Q000276:immunology*; D000818:Animals; D004372:Ducks / Q000276:immunology / Q000821:virology*; D009980:Influenza A virus / Q000472:pathogenicity*; D005585:Influenza in Birds / Q000821:virology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017201:Virus Shedding