title: Evidence of infection by H5N2 highly pathogenic avian influenza viruses in healthy wild waterfowl.
abstract: The potential existence of a wild bird reservoir for highly pathogenic avian influenza (HPAI) has been recently questioned by the spread and the persisting circulation of H5N1 HPAI viruses, responsible for concurrent outbreaks in migratory and domestic birds over Asia, Europe, and Africa. During a large-scale surveillance programme over Eastern Europe, the Middle East, and Africa, we detected avian influenza viruses of H5N2 subtype with a highly pathogenic (HP) viral genotype in healthy birds of two wild waterfowl species sampled in Nigeria. We monitored the survival and regional movements of one of the infected birds through satellite telemetry, providing a rare evidence of a non-lethal natural infection by an HP viral genotype in wild birds. Phylogenetic analysis of the H5N2 viruses revealed close genetic relationships with H5 viruses of low pathogenicity circulating in Eurasian wild and domestic ducks. In addition, genetic analysis did not reveal known gallinaceous poultry adaptive mutations, suggesting that the emergence of HP strains could have taken place in either wild or domestic ducks or in non-gallinaceous species. The presence of coexisting but genetically distinguishable avian influenza viruses with an HP viral genotype in two cohabiting species of wild waterfowl, with evidence of non-lethal infection at least in one species and without evidence of prior extensive circulation of the virus in domestic poultry, suggest that some strains with a potential high pathogenicity for poultry could be maintained in a community of wild waterfowl.
authors.affiliation: Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Montpellier, France. nicolas.gaidet@cirad.fr
authors.forename: Nicolas
authors.initials: N
authors.lastname: Gaidet
authors.forename: Giovanni
authors.initials: G
authors.lastname: Cattoli
authors.forename: Saliha
authors.initials: S
authors.lastname: Hammoumi
authors.forename: Scott H
authors.initials: SH
authors.lastname: Newman
authors.forename: Ward
authors.initials: W
authors.lastname: Hagemeijer
authors.forename: John Y
authors.initials: JY
authors.lastname: Takekawa
authors.forename: Julien
authors.initials: J
authors.lastname: Cappelle
authors.forename: Tim
authors.initials: T
authors.lastname: Dodman
authors.forename: Tony
authors.initials: T
authors.lastname: Joannis
authors.forename: Patricia
authors.initials: P
authors.lastname: Gil
authors.forename: Isabella
authors.initials: I
authors.lastname: Monne
authors.forename: Alice
authors.initials: A
authors.lastname: Fusaro
authors.forename: Ilaria
authors.initials: I
authors.lastname: Capua
authors.forename: Shiiwuua
authors.initials: S
authors.lastname: Manu
authors.forename: Pierfrancesco
authors.initials: P
authors.lastname: Micheloni
authors.forename: Ulf
authors.initials: U
authors.lastname: Ottosson
authors.forename: John H
authors.initials: JH
authors.lastname: Mshelbwala
authors.forename: Juan
authors.initials: J
authors.lastname: Lubroth
authors.forename: Joseph
authors.initials: J
authors.lastname: Domenech
authors.forename: François
authors.initials: F
authors.lastname: Monicat
mesh_terms: D000818:Animals; D001483:Base Sequence; D001717:Birds; D004372:Ducks / Q000821:virology*; D005838:Genotype; D053125:Influenza A Virus, H5N2 Subtype / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity; D005585:Influenza in Birds / Q000235:genetics* / Q000635:transmission; D008969:Molecular Sequence Data; D009549:Nigeria; D010802:Phylogeny