Phylogenetic Analysis of H6 Influenza Viruses Isolated from Rosy-Billed Pochards (Netta peposaca) in Argentina Reveals the Presence of Different HA Gene Clusters

RIMONDI, AGUSTINA; XU, KEMIN; CRAIG, MARIA ISABEL; SHAO, HONGXIA; FERREYRA, HEBE DEL VALLE; RAGO, VIRGINIA; ROMANO, MARCELO; UHART, MARCELA; SUTTON, TROY; FERRERO, ANDREA; PEREZ, DANIEL R.; PEREDA, ARIEL J.

JOURNAL OF VIROLOGY

AMER SOC MICROBIOLOGY

Lugar: Washington; Año: 2011 vol. 85 p. 13354 - 13362

0022-538X

Until recently, influenza A viruses from wild waterfowl in South America were rarely isolated and/orcharacterized. To explore the ecology of influenza A viruses in this region, a long-term surveillance programwas established in 2006 for resident and migratory water birds in Argentina. We report the characterizationof 5 avian influenza viruses of the H6 hemagglutinin (HA) subtype isolated from rosy-billed pochards (Nettapeposaca). Three of these viruses were paired to an N2 NA subtype, while the other two were of the N8 subtype.Genetic and phylogenetic analyses of the internal gene segments revealed a close relationship with influenzaviruses from South America, forming a unique clade and supporting the notion of independent evolution frominfluenza A viruses in other latitudes. The presence of NS alleles A and B was also identified. The HA and NAgenes formed unique clades separate from North American and Eurasian viruses, with the exception of the HAgene of one isolate, which was more closely related to the North American lineage, suggesting possibleinteractions between viruses of North American and South American lineages. Animal studies suggested thatthese Argentine H6 viruses could replicate and transmit inefficiently in chickens, indicating limited adaptationto poultry. Our results highlight the importance of continued influenza virus surveillance in wild birds of SouthAmerica, especially considering the unique evolution of these viruses.