Strategies to Achieve HIV and HCV Infection Incidence Targets Among People Who Inject Drugs: A Stochastic Network-Based Multi-Disease Transmission Modeling Study

BackgroundThe United States aims to reduce the incidence of human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections by 90% by 2030. ObjectiveTo identify strategies for achieving incidence reduction goals by scaling interventions that address the syndemic of substance use disorder, HIV infection, and HCV infection among people who inject drugs (PWID). DesignStochastic agent-based multiplex network model. SettingUrban areas in the United States. ParticipantsPeople who inject drugs. InterventionsScenarios scaled interventions from current baseline to moderate and high values. Prevention and cessation interventions were increased 15 (moderate) and 30 (high) percentage points. Test and treat interventions increased the percentage of PWID with current HCV infection achieving sustained virologic response per year from 3% to 16% (moderate) and 28% (high) and the percentage of PWID with HIV that were virally suppressed from 44% to 58% (moderate) and 71% (high). MeasurementsHIV and HCV infection incidence among PWID over ten years, and quality-adjusted life-years, discounted at 3% annually, over 80 years. ResultsHigh coverage across all three intervention strategies resulted in an 86% (95% Uncertainty Interval (UI): 72-96%) decrease in new HIV infections, a 90% (95% UI: 87-94%) decrease in new HCV infections, and an increase of 1.8 (95% UI: 1.6-2.0) discounted quality-adjusted life-years among PWID. Moderate coverage across all three strategies yielded 62% (95% UI: 39-81%) and 68% (95% UI: 61-74%) decreases in new HIV and HCV infections among PWID, respectively. Increasing cessation of injection consistently produced the largest gains in quality-adjusted life-years. LimitationsModel did not examine specific interventions or economic costs. Parameters were not representative of all urban areas or all PWID. ConclusionIncreases in survival and health-related quality of life for PWID can be achieved by scaling syndemic-focused intervention strategies. Primary Funding SourceThis project was funded by the Centers for Disease Control and Prevention, National Center for HIV, Viral Hepatitis, STD, and TB Prevention Epidemiologic and Economic Modeling Agreement (NEEMA; award #NU38PS004651) and the National Institute on Drug Abuse. Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the official position of the Centers for Disease Control and Prevention, the National Institutes of Health, or authors affiliated institutions.