title: HIV-infected men who have sex with men who identify themselves as belonging to subcultures are at increased risk for hepatitis C infection.
abstract: BACKGROUND
  Hepatitis C virus (HCV) emerged as sexually transmitted infection among HIV-infected men who have sex with men (MSM). We studied whether HCV circulated in identifiable high-risk MSM subcultures and performed phylogenetic analysis.
  
  
  METHODS
  HIV-infected MSM were recruited at the sexually transmitted infections (STI) outpatient clinic and a university HIV clinic in Amsterdam, the Netherlands, 2008-2009. Participants completed a detailed questionnaire and were tested for HCV antibodies and RNA, with NS5B regions sequenced for analysis of clusters.
  
  
  RESULTS
  Among 786 participants, the median age was 43 (IQR 37-48) years, and 93 (11.8%) were HCV-positive. Seropositivity was associated with belonging to subcultures identified as leather (aOR 2.60; 95% CI 1.56-4.33), rubber/lycra (aOR 2.15; 95% CI 1.10-4.21), or jeans (aOR 2.23; 95% CI 1.41-3.54). The two largest HCV-RNA monophyletic clusters were compared; MSM in cluster I (genotype 1a, n = 13) reported more partners (P = 0.037) than MSM in cluster II (genotype 4d, n = 14), but demographics, subculture characteristics and other risk behaviors did not differ significantly between the two clusters.
  
  
  CONCLUSIONS
  HCV infection is associated with identifiable groups of leather/rubber/lycra/jeans subcultures among HIV-infected MSM. Separate epidemiological HCV transmission networks were not revealed. Active HCV screening and treatment within specific subcultures may reduce HCV spread among all MSM.
authors.affiliation: Cluster of Infectious Diseases, Public Health Service of Amsterdam, Amsterdam, The Netherlands. amatser@ggd.amsterdam.nl
authors.forename: Amy
authors.initials: A
authors.lastname: Matser
authors.forename: Joost
authors.initials: J
authors.lastname: Vanhommerig
authors.forename: Maarten F
authors.initials: MF
authors.lastname: Schim van der Loeff
authors.forename: Ronald B
authors.initials: RB
authors.lastname: Geskus
authors.forename: Henry J C
authors.initials: HJ
authors.lastname: de Vries
authors.forename: Jan M
authors.initials: JM
authors.lastname: Prins
authors.forename: Maria
authors.initials: M
authors.lastname: Prins
authors.forename: Sylvia M
authors.initials: SM
authors.lastname: Bruisten
mesh_terms: D000328:Adult; D003466:Cultural Characteristics; D006678:HIV; D015658:HIV Infections / Q000097:blood* / Q000150:complications / Q000276:immunology; D016174:Hepacivirus / Q000276:immunology*; D006526:Hepatitis C / Q000097:blood* / Q000150:complications / Q000276:immunology / Q000635:transmission*; D018937:Hepatitis C Antibodies / Q000097:blood*; D018451:Homosexuality, Male / Q000523:psychology; D006801:Humans; D008297:Male; D012307:Risk Factors; D012309:Risk-Taking; D012725:Sexual Behavior / Q000523:psychology
chemical_list: D018937:Hepatitis C Antibodies