title: [Genetic characteristics of entervirus 71 isolated in Ningxia Hui Autonomous region in 2009].
abstract: OBJECTIVE
  To analyze the genetic characteristics of EV71 strains isolated from HFMD cases in Ningxia Hui Autonomous Region in 2009.
  
  
  METHODS
  In 2009, totally 385 specimens from 344 HFMD cases were collected from Ningxia. Enterovirus isolation was performed in RD cell line from all the specimens. EV71 isolates were identified by specific RT-PCR from the positive cultures, and sequences of complete EV71 VP1 encoding region were determined for farther analyses.
  
  
  RESULTS
  Totally from 126 EV strains isolated in this study, 58 EV71 strains (46%) were identified. And complete VP1 sequences of 46 EV71 strains were determined, and genetic analyses were performed. It was showed that the nucleotide identity of 46 Ningxia strains with the representatives of A and B genotypes were 81.7%-82.8% and 83.1%-85.2%, and the amino acid identity were 93.9%-95.9% and 96. 2%-97.9% respectively. The nucleotide identity of NingXia EV71 isolates with representatives of subgenotype C1, C2, C3, C4a, C4b, and C5 were 88.3%-90.6% (97.9%-99.6%), 88.3%-90.1% (97.9%-99.3%), 87.8%-89.0% (97.6%-98.9%), 94.2%-98.9% (97.9%-100%), 91.8%-94.1% (98.6%-99.6%), and 86.7%-89.1% (97.9%-98.9%). Phylogenetic tree analysis revealed that 46 stains were clustered with reference stains of subgenotype C4 and the Ningxia EV71 isolates were belonged to subgenotype C4a.
  
  
  CONCLUSIONS
  EV71 of subgenotype C4a had spread widely in Ningxia in 2009, which was absolutely predominant type in Ningxia in 2009 and also as the predominant type in China mainland since 2005.
authors.affiliation: Ningxia Hui Autonomous Region Center for Disease Control and Prevention, Yinchuan 750004, China.
authors.forename: Jiang-tao
authors.initials: JT
authors.lastname: Ma
authors.forename: Hui
authors.initials: H
authors.lastname: Chen
authors.forename: Xue-ming
authors.initials: XM
authors.lastname: Ma
authors.forename: Guang-yu
authors.initials: GY
authors.lastname: Guan
authors.forename: Qiong
authors.initials: Q
authors.lastname: Hao
authors.forename: Qiu-fang
authors.initials: QF
authors.lastname: Wen
authors.forename: Xiao-qiang
authors.initials: XQ
authors.lastname: Sun
authors.forename: Dong-zhi
authors.initials: DZ
authors.lastname: Yang
authors.forename: Zhong-lan
authors.initials: ZL
authors.lastname: Wu
authors.forename: Jun
authors.initials: J
authors.lastname: Zhan
authors.forename: Xiao-juan
authors.initials: XJ
authors.lastname: Tan
authors.forename: Wen-bo
authors.initials: WB
authors.lastname: Xu
mesh_terms: D036022:Capsid Proteins / Q000235:genetics; D002681:China / Q000453:epidemiology; D029821:Enterovirus A, Human / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D005260:Female; D006232:Hand, Foot and Mouth Disease / Q000453:epidemiology / Q000821:virology*; D006801:Humans; D008969:Molecular Sequence Data; D010802:Phylogeny
chemical_list: D036022:Capsid Proteins