title: Can needle and syringe programmes and opiate substitution therapy achieve substantial reductions in hepatitis C virus prevalence? Model projections for different epidemic settings.
abstract: OBJECTIVE
  To investigate the impact of scaling-up opiate substitution therapy (OST) and high coverage needle and syringe programmes (100%NSP-obtaining more sterile syringes than you inject) on HCV prevalence among injecting drug users (IDUs).
  
  
  METHODS
  Hepatitis C virus HCV transmission modelling using U.K. estimates for effect of OST and 100%NSP on individual risk of HCV infection.
  
  
  METHODS
  Range of chronic HCV prevalent (20/40/60%) settings with no OST/100%NSP, and U.K. setting with 50% coverage of both OST and 100%NSP.
  
  
  METHODS
  Injecting drug users.
  
  
  METHODS
  Decrease in HCV prevalence after 5-20 years due to scale-up of OST and 100%NSP to 20/40/60% coverage in no OST/100%NSP settings, or from 50% to 60/70/80% coverage in the U.K. setting.
  
  
  RESULTS
  For 40% chronic HCV prevalence, scaling-up OST and 100%NSP from 0% to 20% coverage reduces HCV prevalence by 13% after 10 years. This increases to a 24/33% relative reduction at 40/60% coverage. Marginally less impact occurs in higher prevalence settings over 10 years, but this becomes more pronounced over time. In the United Kingdom, without current coverage levels of OST and 100%NSP the chronic HCV prevalence could be 65% instead of 40%. However, increasing OST and 100%NSP coverage further is unlikely to reduce chronic prevalence to less than 30% over 10 years unless coverage becomes ≥80%.
  
  
  CONCLUSIONS
  Scaling-up opiate substitution therapy and high coverage needle and syringe programmes can reduce hepatitis C prevalence among injecting drug users, but reductions can be modest and require long-term sustained intervention coverage. In high coverage settings, other interventions are needed to further decrease hepatitis C prevalence. In low coverage settings, sustained scale-up of both interventions is needed.
authors.affiliation: London School of Hygiene and Tropical Medicine, London, UK. peter.vickerman@lshtm.ac.uk
authors.forename: Peter
authors.initials: P
authors.lastname: Vickerman
authors.forename: Natasha
authors.initials: N
authors.lastname: Martin
authors.forename: Katy
authors.initials: K
authors.lastname: Turner
authors.forename: Matthew
authors.initials: M
authors.lastname: Hickman
mesh_terms: D019698:Hepatitis C, Chronic / Q000453:epidemiology / Q000517:prevention & control*; D006801:Humans; D008954:Models, Biological; D018671:Needle-Exchange Programs; D058850:Opiate Substitution Treatment; D009293:Opioid-Related Disorders / Q000453:epidemiology / Q000534:rehabilitation*; D015995:Prevalence; D015819:Substance Abuse, Intravenous / Q000453:epidemiology / Q000534:rehabilitation*; D006113:United Kingdom / Q000453:epidemiology