title: The zoonotic potential of avian influenza viruses isolated from wild waterfowl in Zambia.
abstract: Whilst remarkable progress in elucidating the mechanisms governing interspecies transmission and pathogenicity of highly pathogenic avian influenza viruses (AIVs) has been made, similar studies focusing on low-pathogenic AIVs isolated from the wild waterfowl reservoir are limited. We previously reported that two AIV strains (subtypes H6N2 and H3N8) isolated from wild waterfowl in Zambia harbored some amino acid residues preferentially associated with human influenza virus proteins (so-called human signatures) and replicated better in the lungs of infected mice and caused more morbidity than a strain lacking such residues. To further substantiate these observations, we infected chickens and mice intranasally with AIV strains of various subtypes (H3N6, H3N8, H4N6, H6N2, H9N1 and H11N9) isolated from wild waterfowl in Zambia. Although some strains induced seroconversion, all of the tested strains replicated poorly and were nonpathogenic for chickens. In contrast, most of the strains having human signatures replicated well in the lungs of mice, and one of these strains caused severe illness in mice and induced lung injury that was characterized by a severe accumulation of polymorphonuclear leukocytes. These results suggest that some strains tested in this study may have the potential to infect mammalian hosts directly without adaptation, which might possibly be associated with the possession of human signature residues. Close monitoring and evaluation of host-associated signatures may help to elucidate the prevalence and emergence of AIVs with potential for causing zoonotic infections.
authors.affiliation: Division of Global Epidemiology, Hokkaido University Research Center for Zoonosis Control, Kita-20, Nishi-10, Kita-ku, Sapporo, 001-0020, Japan.
authors.forename: Edgar
authors.initials: E
authors.lastname: Simulundu
authors.forename: Naganori
authors.initials: N
authors.lastname: Nao
authors.forename: John
authors.initials: J
authors.lastname: Yabe
authors.forename: Nilton A
authors.initials: NA
authors.lastname: Muto
authors.forename: Thami
authors.initials: T
authors.lastname: Sithebe
authors.forename: Hirofumi
authors.initials: H
authors.lastname: Sawa
authors.forename: Rashid
authors.initials: R
authors.lastname: Manzoor
authors.forename: Masahiro
authors.initials: M
authors.lastname: Kajihara
authors.forename: Mieko
authors.initials: M
authors.lastname: Muramatsu
authors.forename: Akihiro
authors.initials: A
authors.lastname: Ishii
authors.forename: Hirohito
authors.initials: H
authors.lastname: Ogawa
authors.forename: Aaron S
authors.initials: AS
authors.lastname: Mweene
authors.forename: Ayato
authors.initials: A
authors.lastname: Takada
mesh_terms: D000818:Animals; D000835:Animals, Wild / Q000821:virology; D002645:Chickens; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D053123:Influenza A Virus, H3N8 Subtype / Q000276:immunology / Q000302:isolation & purification / Q000472:pathogenicity*; D005585:Influenza in Birds; D007251:Influenza, Human / Q000821:virology; D008168:Lung / Q000276:immunology / Q000473:pathology* / Q000821:virology; D051379:Mice; D008807:Mice, Inbred BALB C; D009504:Neutrophils / Q000276:immunology; D015024:Zambia