title: Isolation and characterization of H6N1 and H9N2 avian influenza viruses from Ducks in Hanoi, Vietnam.
abstract: We report the genetic characterization of low pathogenic avian influenza (LPAI) viruses isolated from domestic ducks in northern Vietnam in 2009. In total, 22 influenza A viruses consisting of 21 H6N1 subtypes and one H9N2 subtype were isolated from 1488 ducks collected in February, March, and April 2009, accounting the overall virus isolation rate for 1.5%. No H5N1 strain was isolated in this study. Phylogenetic analysis indicated that all the eight genes of the H6N1 and H9N2 subtypes analyzed in this study were similar to those isolated in Korea, southeast China and northern Japan, and wild birds which migrate along the coastal East Asian Flyway are estimated to transmit these viruses. There was no evidence that the H6N1 and H9N2 subtypes share the gene segments with H5N1 subtypes. However, it is important to monitor the prevalence and genetical backgrounds of LPAI viruses among poultry in an area where several different influenza A subtypes are in circulation.
authors: Center for Infectious Disease Research in Asia and Africa, Institute of Tropical Medicine, Nagasaki University, 1-12-4 Sakamoto, Nagasaki 852-8523, Japan.
authors: Kozue
authors: K
authors: Hotta
authors: Hiroki
authors: H
authors: Takakuwa
authors: Quynh Mai Thi
authors: QM
authors: Le
authors: Song Lien
authors: SL
authors: Phuong
authors: Toshiyuki
authors: T
authors: Murase
authors: Etsuro
authors: E
authors: Ono
authors: Toshihiro
authors: T
authors: Ito
authors: Koichi
authors: K
authors: Otsuki
authors: Tetsu
authors: T
authors: Yamashiro
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D004372:Ducks / Q000821:virology*; D005838:Genotype; D009980:Influenza A virus / Q000145:classification* / Q000302:isolation & purification*; D005585:Influenza in Birds / Q000821:virology*; D017720:Molecular Epidemiology; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D017422:Sequence Analysis, DNA; D014744:Vietnam
chemical_list: D012367:RNA, Viral