title: Complex patterns of HCV epidemic in Suzhou: evidence for dual infection and HCV recombination in East China.
abstract: BACKGROUND
  HCV transmission is closely associated with injection drug use (IDU), and co-circulation of multiple subtypes has been found among injection drug users (IDUs) in China.
  
  
  OBJECTIVE
  To investigate HCV subtype characterizations among IDUs and general population (GP) in Suzhou, a city at the important "Hu-ning" transportation line.
  
  
  METHODS
  During January 2010 to May 2011, 123 HCV positive plasma from IDUs and 131 stored HCV positive sera from general individuals were collected in Suzhou. HCV C/E2 and NS5B fragments were amplified using a new multiple RT-nested PCR strategy and subsequent sequenced. Genotypes were characterized by phylogenetic analyses.
  
  
  RESULTS
  Eight HCV subtypes (1a, 1b, 2a, 3a, 3b, 6a, 6n, and 6u) were detected among Suzhou IDUs, and six subtypes (1b, 2a, 3a, 3b, 6a and 6n) among GP. HCV subtype distribution is distinct between IDUs and GP. Interestingly, we detected discrepancy of genotyping results between C/E2 and NS5B regions in one general individual, indicating the presence of HCV intersubtype recombinant in China. The recombinant belongs to a 3a/1b recombinant. We also detected dual infections in one general individual and two IDUs. They include dual infections between 1b and 3a, 3a and 6a, and two distinct lineages of 3b.
  
  
  CONCLUSIONS
  Complex patterns of HCV epidemic among IDUs, as well as GP, in Suzhou, might imply a spread of HCV from IDUs to GP. The finding of one HCV 3a/1b intersubtype recombinant might represent the first report of HCV recombination in China.
authors.affiliation: Clinical Laboratory, The Second Affiliated Hospital of Soochow University, 1055 Sanxiang Road, Suzhou, Jiangsu 215004, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Du
authors.forename: Yinle
authors.initials: Y
authors.lastname: Qi
authors.forename: Fangyuan
authors.initials: F
authors.lastname: Hao
authors.forename: Yan
authors.initials: Y
authors.lastname: Huang
authors.forename: Lingxiang
authors.initials: L
authors.lastname: Mao
authors.forename: Shunfeng
authors.initials: S
authors.lastname: Ji
authors.forename: Mingyuan
authors.initials: M
authors.lastname: Huang
authors.forename: Chenhao
authors.initials: C
authors.lastname: Qin
authors.forename: Ruhong
authors.initials: R
authors.lastname: Yan
authors.forename: Xueming
authors.initials: X
authors.lastname: Zhu
authors.forename: Chiyu
authors.initials: C
authors.lastname: Zhang
mesh_terms: D002681:China / Q000453:epidemiology; D016000:Cluster Analysis; D005838:Genotype; D016174:Hepacivirus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification*; D006526:Hepatitis C / Q000453:epidemiology* / Q000635:transmission / Q000821:virology*; D006801:Humans; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012367:RNA, Viral / Q000235:genetics; D011995:Recombination, Genetic; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA; D015819:Substance Abuse, Intravenous / Q000150:complications; D014764:Viral Proteins / Q000235:genetics
chemical_list: D012367:RNA, Viral; D014764:Viral Proteins