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Expanding Needle/syringe Exchange Programs

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Reusing or sharing drug injecting equipment increases transmission of bloodborne infections like human immunodeficiency virus (HIV) and hepatitis C virus (HCV). Forty-four states are at high risk of HIV or Hepatitis C outbreaks due to injection drug use. Syringe exchange programs (SEPs) provide people who inject drugs (PWID) with sterile injection equipment, a safe disposal site for used equipment, and advice on reducing injection risk. However, as of 2020, 27 US states have four or fewer SEPs, including nine with none, reflecting doubts about the value of SEPs among policymakers and the public.



  • SEPs generally reduce rather than eradicate needle-sharing. But such reductions are sufficient to generate large benefits. Studies conducted in New York City and Washington, DC have found 70% drops in new HIV infections following opening of SEPs.

  • A global systematic review of well-disseminated SEPs found decreases of 33-43%  in population HIV prevalence. SEPs reduce healthcare costs related to treating HIV, saving an estimated $50,000 or more per HIV infection averted, representing a return on investment of 6-fold or more.

  • Because HCV is more transmissible and more prevalent among PWID, the effect of SEPs on HCV incidence is smaller than for HIV. Studies in the U.S., Scotland, Ireland, and Australia have estimated reductions in HCV prevalence between 13-43%

  • Although many believe that SEPs reduce harm but not drug use, SEPs can help PWID reduce injection frequency and enter substance use treatment programs. A Seattle study of people who inject heroin found attending an SEP was associated with a 5-fold increase in initiating methadone treatment. 



Syringe exchange programs are a cost-effective, easily scaledintervention to reduce bloodborne infections among PWID and the broader population. SEPs can also facilitate entry into substance use treatment services. SEPs effectiveness is highest in settings where there are no other sources of sterile syringes, needles, or injecting equipment. This suggests that in jurisdictions without SEPs, policymakers can achieve some of the same benefits by pursuing other policies that expand access to clean injection supplies (e.g., allowing pharmacies to provide needles without a prescription). 


Key Policy Evidence:

  • Coverage is important. A global systematic review of SEPs found population-level decreases of 33 to 43% in HIV prevalence and 13 to 29% in HCV prevalence in settings where at least half of people who inject drugs received at least 10 sterile syringes per year. 

  • SEPs have proved cost-effective in terms of reducing emergency department use. and need for  HIV and HCV treatment

  • Studies find that opening a SEP does not increase discarded needles in public places.

  • SEPs tend to reduce sharing of injection drug equipment, but not completely eliminate it. For example, a 2006 genetic biomarker analysis found that 56% of syringes returned to a Baltimore SEP had evidence of multi-person use.

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