title: Transmission of risk-group specific HIV-1 strains among Dutch drug users for more than 20 years and their replacement by nonspecific strains after switching to low-harm drug practices.
abstract: OBJECTIVE
  To characterize HIV-1 epidemiological networks of men having sex with men (MSM) and drug users (DUs) in the Netherlands for >30 years.
  
  
  METHODS
  Previously, we demonstrated different origin of the HIV-1 epidemics in Dutch MSM and DUs. To achieve the study objectives, risk group-specific genetic markers in the pol gene were examined in 315 participants of the Amsterdam Cohort Studies on HIV/AIDS who were registered as HIV-1 infected in 1981-2011.
  
  
  RESULTS
  Phylogenetic analysis demonstrated circulation of distinct virus strains in the 2 networks, with 98% of viruses of MSM clustering together and apart from strains of 73% DUs. Nine genetic markers that significantly distinguished virus strains specific for DUs were identified, of which 3 were ≥90% conserved. Over the total observation period, only 6% of viruses (4 of MSM and 14 of DUs) clustered with those of the other risk group. Among these sequences, the 3 most conserved genetic markers of that other risk group were 87% conserved.All 4 cases of DU-specific viruses among MSM occurred in 1980s-early 1990s. Viruses nonspecific for DUs were causing new infections among DUs at the rate of 20% till 2002 and replaced DU-specific strains among new infections thereafter, coinciding with switching of DUs to low-harm drug practices.
  
  
  CONCLUSIONS
  Dutch MSM and DUs have remained separate epidemiological networks for decades, despite their geographical and behavioral overlap. Switching to low-harm drug practices among DUs resulted in new infections caused by HIV-1 strains originating from other risk groups.
authors.affiliation: Laboratory of Experimental Virology, Department of Medical Microbiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands.
authors.forename: Vladimir V
authors.initials: VV
authors.lastname: Lukashov
authors.forename: Suzanne
authors.initials: S
authors.lastname: Jurriaans
authors.forename: Margreet
authors.initials: M
authors.lastname: Bakker
authors.forename: Ben
authors.initials: B
authors.lastname: Berkhout
mesh_terms: D015415:Biomarkers; D016000:Cluster Analysis; D015331:Cohort Studies; D005260:Female; D015751:Genes, pol; D015658:HIV Infections / Q000453:epidemiology*; D015497:HIV-1 / Q000235:genetics*; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D058974:Phylogeography / Q000639:trends; D040242:Risk Reduction Behavior; D017422:Sequence Analysis, DNA; D015819:Substance Abuse, Intravenous / Q000453:epidemiology*; D013997:Time Factors
chemical_list: D015415:Biomarkers