Cost-effectiveness of harm reduction in preventing hepatitis C among injection drug users.

OBJECTIVES Hepatitis C (HCV) has emerged as a major epidemic among injection drug users (IDUs), with observed prevalence exceeding 70% in many American and European cities. This article explores the potential of syringe exchange programs (SEPs) to reduce HCV incidence and prevalence. DESIGN A random-mixing epidemiological model is used to examine the potential impact of harm reduction interventions. METHODS Steady-state analysis is used to scrutinize the impact of SEP on HCV incidence and prevalence and to examine the accuracy of short-term incidence analysis in predicting long-run program effects. RESULTS SEP is predicted to have little impact on HCV incidence and prevalence within realistic populations of IDUs. CONCLUSIONS Short-term incidence analysis substantially overstates SEP effectiveness and cost-effectiveness in preventing HCV. More comprehensive harm reduction models, coupled with referral of active IDUs to treatment, must complement syringe exchange to successfully contain highly infectious blood-borne diseases.