title: Isolation and characterization of H7N9 avian influenza A virus from humans with respiratory diseases in Zhejiang, China.
abstract: In 2013, the novel reassortant avian-origin influenza A (H7N9) virus was reported in China. Through enhanced surveillance, infection by the H7N9 virus in humans was first identified in Zhejiang Province. Real-time reverse-transcriptase-polymerase-chain-reaction (RT-PCR) was used to confirm the infection. Embryonated chicken eggs were used for virus isolation from pharyngeal swabs taken from infected human patients. The H7N9 isolates were first identified by the hemagglutination test and electron microscopy, then used for whole genome sequencing. Bioinformatics software was used to construct the phylogenetic tree and for computing the mean rate of evolution of the HA gene in H7Nx and NA in HxN9. Two novel H7N9 avian influenza A viruses (A/Zhejiang/1/2013 and A/Zhejiang/2/2013) were isolated from the positive infection cases. Substitutions were found in both Zhejiang isolates and were identified as human-type viruses. All phylogenetic results indicated that the novel reassortant in H7N9 originated in viruses that infected birds. The sequencing and phylogenetic analysis of the whole genome revealed the mean rate of evolution of the HA gene in H7NX to be 5.74E-3 (95% Highest posterior density: 3.8218E-3 to 7.7873E-3) while the NA gene showed 2.243E-3 (4.378E-4 to 3.79E-3) substitutions per nucleotide site per year. The novel reassortant H7N9 virus was confirmed by molecular methods to have originated in poultry, with the mutations occurring during the spread of the H7N9 virus infection. Live poultry markets played an important role in whole H7N9 circulation.
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Yanjun
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Mao
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Juying
authors.initials: J
authors.lastname: Yan
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Zhang
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Xinying
authors.initials: X
authors.lastname: Wang
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Yin
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Yiyu
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Enfu
authors.initials: E
authors.lastname: Chen
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Huakun
authors.initials: H
authors.lastname: Lv
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Liming
authors.initials: L
authors.lastname: Gong
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Jian
authors.initials: J
authors.lastname: Gao
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Changping
authors.initials: C
authors.lastname: Xu
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Qiong
authors.initials: Q
authors.lastname: Ge
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Baoxiang
authors.initials: B
authors.lastname: Xu
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Fang
authors.initials: F
authors.lastname: Xu
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Zhangnv
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Center for Disease Control and Prevention of Hangzhou, Hangzhou, Zhejiang 310021, China.
authors.forename: Guoqiu
authors.initials: G
authors.lastname: Zhao
authors.affiliation: Center for Disease Control and Prevention of Huzhou, Huzhou, Zhejiang 313000, China.
authors.forename: Jiankang
authors.initials: J
authors.lastname: Han
authors.affiliation: Central Veterinary Institute, Part of Wageningen UR, Virology Department, 8200 AB Lelystad, The Netherlands.
authors.forename: Koch
authors.initials: K
authors.lastname: Guus
authors.affiliation: Shanghai Huirui Biotechnology Co. Ltd., Shanghai 200002, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Li
authors.affiliation: National Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, 155 Changbai Road, Beijing 102206, China.
authors.forename: Yuelong
authors.initials: Y
authors.lastname: Shu
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Zhejiang Provincial Center for Disease Control and Prevention, Hangzhou, Zhejiang 310051, China. Electronic address: Yjzhang@cdc.zj.cn.
authors.forename: Shichang
authors.initials: S
authors.lastname: Xia
mesh_terms: D000328:Adult; D000818:Animals; D002642:Chick Embryo; D002681:China; D016000:Cluster Analysis; D016679:Genome, Viral; D006385:Hemagglutination Inhibition Tests; D006801:Humans; D064766:Influenza A Virus, H7N9 Subtype / Q000145:classification / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D007251:Influenza, Human / Q000821:virology*; D008297:Male; D008854:Microscopy, Electron; D008875:Middle Aged; D010802:Phylogeny; D012367:RNA, Viral / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D014776:Virus Cultivation
chemical_list: D012367:RNA, Viral
keywords: H7N9; Influenza A