title: [Genetic characterization of coxsackievirus A16 isolated in Ningxia Hui Municipality in 2008].
abstract: OBJECTIVE
  To study the genetic characterization of coxsackievirus A16 (CVA16) strains isolated during an epidemic of hand, foot, and mouth disease (HFMD) in Ningxia Hui Municipality in 2008.
  
  
  METHODS
  Clinical samples were collected from HFMD patients in Ningxia Hui Municipality and CVA16 strains were isolated by viral isolation methods. Reverse transcription-polymerase chain reactions (RT-PCR), specific for CVA16 were performed with these CVA16 strains. Entire VP1 coding region amplification and sequencing were then performed and finally phylogenetic tree was constructed among Ningxia CVA16 strains and CVA16 representative strains of known genotypes and subgenotypes.
  
  
  RESULTS
  70 Ningxia CVA16 strains were isolated from HFMD patients in Ningxia in 2008 and the homology of nucleotide and amino acid were 90.8%-100.0% and 98.9% - 100.0%, respectively. Phylogenetic characteristics of the strains reconfirmed that they could be divided into two distinct genotypes-A and B. Genotype B could be further divided into the subgenotypes B1 and B2, while all the 70 Ningxia CVA16 strains belonged to the co-circulated clusters B1a and B1b within subgenotype B1, which belonged to 2 viral transmission chains.
  
  
  CONCLUSIONS
  Our results indicated that subgenotype B1 CVA16 strains continued to circulate over a wide geographic area of mainland China since the first reported episode in Shenzhen city in 1999. Like other CVA16 strains isolated elsewhere in China, both B1a and B1b evolution branches were co-circulating in Ningxia Hui Municipality. Based on the close phylgenetic and chronological relationship with CVA16 isolated in other countries and regions near China. Our data confirmed that these strains co-evolved and co-circulated with those from neighboring countries and regions.
authors.affiliation: Institute for Viral Disease Control and Prevention, Chinese Center for Disease Control and Prevention, State Key Laboratory Molecular Virology & Genetic Engineering, World Health Organization Western Pacific Region Regional Reference Poliovirus Laboratory, Beijing 100050, China.
authors.forename: Dong-Yan
authors.initials: DY
authors.lastname: Wang
authors.forename: Hui
authors.initials: H
authors.lastname: Chen
authors.forename: Dong-Mei
authors.initials: DM
authors.lastname: Yan
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Jun-Jing
authors.initials: JJ
authors.lastname: An
authors.forename: Jiang-Tao
authors.initials: JT
authors.lastname: Ma
authors.forename: Shuang-Li
authors.initials: SL
authors.lastname: Zhu
authors.forename: Xue-Min
authors.initials: XM
authors.lastname: Ma
authors.forename: Hong-Qiu
authors.initials: HQ
authors.lastname: An
authors.forename: Wen-Bo
authors.initials: WB
authors.lastname: Xu
mesh_terms: D002681:China / Q000453:epidemiology; D029821:Enterovirus A, Human / Q000235:genetics; D005838:Genotype; D006232:Hand, Foot and Mouth Disease; D006801:Humans; D010802:Phylogeny