title: Phylogeography and evolutionary history of reassortant H9N2 viruses with potential human health implications.
abstract: Avian influenza viruses of the H9N2 subtype have seriously affected the poultry industry of the Far and Middle East since the mid-1990s and are considered one of the most likely candidates to cause a new influenza pandemic in humans. To understand the genesis and epidemiology of these viruses, we investigated the spatial and evolutionary dynamics of complete genome sequences of H9N2 viruses circulating in nine Middle Eastern and Central Asian countries from 1998 to 2010. We identified four distinct and cocirculating groups (A, B, C, and D), each of which has undergone widespread inter- and intrasubtype reassortments, leading to the generation of viruses with unknown biological properties. Our analysis also suggested that eastern Asia served as the major source for H9N2 gene segments in the Middle East and Central Asia and that in this geographic region within-country evolution played a more important role in shaping viral genetic diversity than migration between countries. The genetic variability identified among the H9N2 viruses was associated with specific amino acid substitutions that are believed to result in increased transmissibility in mammals, as well as resistance to antiviral drugs. Our study highlights the need to constantly monitor the evolution of H9N2 viruses in poultry to better understand the potential risk to human health posed by these viruses.
authors.affiliation: Istituto Zooprofilattico Sperimentale delle Venezie, Research & Development Department, OIE/FAO and National Reference Laboratory for Newcastle Disease and Avian Influenza, OIE Collaborating Center for Diseases at the Human-Animal Interface, Viale dell'Università 10, 35020 Legnaro, Padua, Italy. afusaro@izsvenezie.it
authors.forename: Alice
authors.initials: A
authors.lastname: Fusaro
authors.forename: Isabella
authors.initials: I
authors.lastname: Monne
authors.forename: Annalisa
authors.initials: A
authors.lastname: Salviato
authors.forename: Viviana
authors.initials: V
authors.lastname: Valastro
authors.forename: Alessia
authors.initials: A
authors.lastname: Schivo
authors.forename: Nadim Mukhles
authors.initials: NM
authors.lastname: Amarin
authors.forename: Carlos
authors.initials: C
authors.lastname: Gonzalez
authors.forename: Mahmoud Moussa
authors.initials: MM
authors.lastname: Ismail
authors.forename: Abdu-Rahman
authors.initials: AR
authors.lastname: Al-Ankari
authors.forename: Mohamed Hamad
authors.initials: MH
authors.lastname: Al-Blowi
authors.forename: Owais Ahmed
authors.initials: OA
authors.lastname: Khan
authors.forename: Ali Safar
authors.initials: AS
authors.lastname: Maken Ali
authors.forename: Afshin
authors.initials: A
authors.lastname: Hedayati
authors.forename: Juan
authors.initials: J
authors.lastname: Garcia Garcia
authors.forename: Ghulam M
authors.initials: GM
authors.lastname: Ziay
authors.forename: Abdolhamid
authors.initials: A
authors.lastname: Shoushtari
authors.forename: Kassem Nasser
authors.initials: KN
authors.lastname: Al Qahtani
authors.forename: Ilaria
authors.initials: I
authors.lastname: Capua
authors.forename: Edward C
authors.initials: EC
authors.lastname: Holmes
authors.forename: Giovanni
authors.initials: G
authors.lastname: Cattoli
mesh_terms: D019943:Amino Acid Substitution; D000818:Animals; D001209:Asia, Central; D001483:Base Sequence; D024882:Drug Resistance, Viral / Q000235:genetics; D019143:Evolution, Molecular; D014644:Genetic Variation; D006801:Humans; D053127:Influenza A Virus, H9N2 Subtype / Q000187:drug effects / Q000235:genetics* / Q000472:pathogenicity; D005585:Influenza in Birds / Q000453:epidemiology / Q000821:virology*; D007251:Influenza, Human / Q000453:epidemiology / Q000821:virology*; D008877:Middle East; D010802:Phylogeny; D058974:Phylogeography; D011200:Poultry; D016865:Reassortant Viruses / Q000187:drug effects / Q000235:genetics* / Q000472:pathogenicity; D012306:Risk; D017423:Sequence Analysis, RNA