title: Molecular epidemiology of HCV monoinfection and HIV/HCV coinfection in injection drug users in Liuzhou, Southern China.
abstract: BACKGROUND
  Hepatitis C virus (HCV) mono-infection and HCV/HIV (human immunodeficiency virus) co-infection are growing problems in injection drug users (IDU). Their prevalence and genotypic patterns vary with geographic locations. Access to harm reduction measures is opening up opportunities for improving the HIV/HCV profiling of IDU in China, where IDUs account for a significant proportion of the two infections especially in the southern part of the country.
  
  
  RESULTS
  A cross sectional study was conducted. Through the Liuzhou Methadone Clinic, a total of 117 injection drug users (IDUs) were recruited from Guangxi, Southern China. A majority of the IDUs (96%) were HCV antibody positive, of which 21% were HIV infected. Unlike HCV monoinfection, there was spatial heterogeneity in the distribution of HIV/HCV coinfection, the latter also characterized by a higher prevalence of needle-sharing. Phylogenetic analysis revealed that genotype 6a was predominant in the study population. There were shorter genetic distances among the 6a sequences compared to the other HCV subtypes-1a, 3a, and 3b.
  
  
  CONCLUSIONS
  The results suggested that HIV and HCV were introduced at around the same time to the IDU populations in Southern China, followed by their differential spread as determined by the biologic characteristics of the virus and the intensity of behavioural risk. This pattern is different from that in other South East Asian countries where HCV infections have probably predated HIV.
authors.affiliation: Stanley Ho Centre for Emerging Infectious Diseases, The Chinese University of Hong Kong, Hong Kong, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Tan
authors.forename: Qi Hou
authors.initials: QH
authors.lastname: Wei
authors.forename: Liu Jun
authors.initials: LJ
authors.lastname: Chen
authors.forename: Pui Chung
authors.initials: PC
authors.lastname: Chan
authors.forename: Wen Sheng
authors.initials: WS
authors.lastname: Lai
authors.forename: Ming Liang
authors.initials: ML
authors.lastname: He
authors.forename: Hsiang Fu
authors.initials: HF
authors.lastname: Kung
authors.forename: Shui Shan
authors.initials: SS
authors.lastname: Lee
mesh_terms: D000328:Adult; D002681:China / Q000453:epidemiology; D015897:Comorbidity; D004279:DNA, Viral / Q000032:analysis / Q000302:isolation & purification; D055030:Drug Users / Q000706:statistics & numerical data*; D005260:Female; D006678:HIV / Q000235:genetics / Q000302:isolation & purification*; D015658:HIV Infections / Q000453:epidemiology* / Q000235:genetics; D016174:Hepacivirus / Q000235:genetics / Q000302:isolation & purification*; D006526:Hepatitis C / Q000453:epidemiology* / Q000235:genetics; D006801:Humans; D008297:Male; D017720:Molecular Epidemiology; D016485:Needle Sharing / Q000706:statistics & numerical data; D015995:Prevalence; D012309:Risk-Taking; D016036:Seroepidemiologic Studies; D015819:Substance Abuse, Intravenous / Q000453:epidemiology*; D055815:Young Adult
chemical_list: D004279:DNA, Viral