title: The Molecular Epidemiological Study of HCV Subtypes among Intravenous Drug Users and Non-Injection Drug Users in China.
abstract: BACKGROUND
  More than half of intravenous drug users (IDUs) in China suffer from the Hepatitis C virus (HCV). The virus is also more prevalent in non-injection drug users (NIDUs) than in the general population. However, not much is known about HCV subtype distribution in these populations.
  
  
  METHODS
  Our research team conducted a cross-sectional study in four provinces in China. We sampled 825 IDUs and 244 NIDUs (1162 total), genotyped each DU's virus, and performed a phylogenetic analysis to differentiate HCV subtypes.
  
  
  RESULTS
  Nucleic acid testing (NAT) determined that 82% percent (952/1162) of samples were HCV positive; we subtyped 90% (859/952) of these. We found multiple HCV subtypes: 3b (249, 29.0%), 3a (225, 26.2%), 6a (156, 18.2%), 1b (137, 15.9%), 6n (50, 5.9%), 1a (27, 3.1%), and 2a (15, 1.7%). An analysis of subtype distributions adjusted for province found statistically significant differences between HCV subtypes in IDUs and NIDUs.
  
  
  CONCLUSIONS
  HCV subtypes 3b, 3a, 6a, and 1b were the most common in our study, together accounting for 89% of infections. The subtype distribution differences we found between IDUs and NIDUs suggested that sharing syringes was not the most likely pathway for HCV transmission in NIDUs. However, further studies are needed to elucidate how NIDUs were infected.
authors.affiliation: Vanderbilt Institution for Global Health, Vanderbilt University, Nashville, Tennessee, United States of America.
authors.forename: Jun
authors.initials: J
authors.lastname: Tao
authors.affiliation: National AIDS Reference Laboratory (NARL), National Center for AIDS/STD Control and Prevention (NCAIDS), Chinese Center for Disease Control and Prevention (China CDC), Beijing, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Liang
authors.affiliation: National AIDS Reference Laboratory (NARL), National Center for AIDS/STD Control and Prevention (NCAIDS), Chinese Center for Disease Control and Prevention (China CDC), Beijing, China.
authors.forename: Hui
authors.initials: H
authors.lastname: Zhang
authors.affiliation: National AIDS Reference Laboratory (NARL), National Center for AIDS/STD Control and Prevention (NCAIDS), Chinese Center for Disease Control and Prevention (China CDC), Beijing, China.
authors.forename: Lijian
authors.initials: L
authors.lastname: Pei
authors.affiliation: Vanderbilt Institution for Global Health, Vanderbilt University, Nashville, Tennessee, United States of America; Department of Medicine, Vanderbilt University, Nashville, Tennessee, United States of America.
authors.forename: Han-Zhu
authors.initials: HZ
authors.lastname: Qian
authors.affiliation: Department of Biomedical Informatics, Vanderbilt University, Nashville, Tennessee, United States of America.
authors.forename: Matthew C
authors.initials: MC
authors.lastname: Chambers
authors.affiliation: National AIDS Reference Laboratory (NARL), National Center for AIDS/STD Control and Prevention (NCAIDS), Chinese Center for Disease Control and Prevention (China CDC), Beijing, China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Jiang
authors.affiliation: National AIDS Reference Laboratory (NARL), National Center for AIDS/STD Control and Prevention (NCAIDS), Chinese Center for Disease Control and Prevention (China CDC), Beijing, China.
authors.forename: Yao
authors.initials: Y
authors.lastname: Xiao
mesh_terms: D000328:Adult; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D055030:Drug Users; D005260:Female; D005838:Genotype; D016174:Hepacivirus / Q000235:genetics*; D006526:Hepatitis C / Q000453:epidemiology* / Q000635:transmission / Q000821:virology*; D006801:Humans; D008297:Male; D010802:Phylogeny; D012367:RNA, Viral; D015819:Substance Abuse, Intravenous / Q000453:epidemiology*; D017361:Viral Nonstructural Proteins / Q000235:genetics; D012324:RNA-Dependent RNA Polymerase
chemical_list: D012367:RNA, Viral; D017361:Viral Nonstructural Proteins; C087036:NS-5 protein, hepatitis C virus; D012324:RNA-Dependent RNA Polymerase