title: Genetic characterization of influenza A virus subtype H7N1 isolated from quail, Thailand.
abstract: In Thailand, surveillance for the highly pathogenic avian influenza virus H5N1 (HPAI-H5N1) has revealed high prevalence of the virus in quail in live-bird markets. This study monitored avian influenza viruses (AIVs) in quail farms in an area at high risk for HPAI-H5N1 over a 12-month period from 2009 to 2010. One-step real-time RT-PCR (rRT-PCR) results showed that 1.18 % of swab samples (24/2,040) were AIV positive. Among the rRT-PCR positive samples, three samples were identified as subtype H7N1. One Thai H7N1 virus designated "A/quail/Thailand/CU-J2882/2009 (H7N1)" was subjected to whole genome sequencing and genetic characterization. Phylogenetic analysis showed that the HA gene of the Thai H7N1 virus groups with those of the H7 Eurasian viruses. Interestingly, the NA gene of the virus was found to be closely related to those of the HPAI-H5N1 viruses from Vietnam and Thailand. This study constitutes the first report on AIV H7N1 in Thailand. Our results suggest the possibility of genetic reassortment between AIV-H7NX and HPAI-H5N1 in quail. The HA cleavage site of the Thai H7N1 virus contains no multiple amino acid insertions, suggesting low pathogenic characteristics for this virus.
authors.affiliation: Center of Excellence for Emerging and Re-emerging Infectious Diseases in Animals, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, 10330, Thailand, manoosak.w@hotmail.com.
authors.forename: Manoosak
authors.initials: M
authors.lastname: Wongphatcharachai
authors.forename: Trong
authors.initials: T
authors.lastname: Wisedchanwet
authors.forename: Nutthawan
authors.initials: N
authors.lastname: Nonthabenjawan
authors.forename: Waleemas
authors.initials: W
authors.lastname: Jairak
authors.forename: Supassama
authors.initials: S
authors.lastname: Chaiyawong
authors.forename: Napawan
authors.initials: N
authors.lastname: Bunpapong
authors.forename: Alongkorn
authors.initials: A
authors.lastname: Amonsin
mesh_terms: D000818:Animals; D016000:Cluster Analysis; D016679:Genome, Viral; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000235:genetics; D057916:Influenza A Virus, H7N1 Subtype / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D005585:Influenza in Birds / Q000821:virology*; D008969:Molecular Sequence Data; D009439:Neuraminidase / Q000235:genetics; D010802:Phylogeny; D011784:Quail / Q000821:virology*; D012367:RNA, Viral / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D017385:Sequence Homology; D013785:Thailand; D014764:Viral Proteins / Q000235:genetics
chemical_list: D019267:Hemagglutinin Glycoproteins, Influenza Virus; D012367:RNA, Viral; D014764:Viral Proteins; C487630:NA protein, influenza A virus; D009439:Neuraminidase