Abstract
BACKGROUND: In Haiphong, Vietnam, most hepatitis C virus (HCV) infections occur among people who inject drugs (PWID). As part of multiple respondent-driven sampling (RDS) surveys among PWID in Haiphong, an intervention (DRIVE-C) provided HCV testing and treatment in 2019. Centres providing opiate agonist treatment (OAT) or antiretroviral therapy (ART) also provided HCV testing and linkage-to-treatment in 2021/22. We modelled the impact and cost-effectiveness of HCV testing and treatment for PWID in Haiphong.
METHODS: An HCV transmission model among PWID and former injectors was calibrated in a Bayesian framework using data from Haiphong. A status quo (SQ) scenario modelled past interventions, with no future HCV treatment. A future intervention scenario modelled the impact of providing HCV testing and linkage-to-treatment in OAT and ART centres, and annual RDS survey interventions over 2025-2030, each testing 1400 PWID. We estimated the incremental cost-effectiveness ratio (ICER) per disability adjusted life-year (DALY) averted for the future scenario compared to SQ over 2025-2054 (3 % annual discount rate).
RESULTS: For the SQ scenario, HCV incidence decreased from 8.1 (95 % credibility interval 5.1-13.6) per 100 person-years (/100pyrs) in 2015 to 5.3/100pyrs (3.0-9.6) in 2023 and increases to 6.2/100pyrs (3.5-10.7) in 2030. In the future intervention scenario, incidence decreases to 2.7/100pyrs (1.0-6.4) by 2030. The mean ICER is €884/DALY averted; cost-effective at a willingness-to-pay threshold of €2334 (57 % of Vietnam's 2023 GDP per capita).
CONCLUSIONS: Using RDS surveys and other care settings to scale-up HCV-testing and treatment are cost-effective strategies to reduce HCV incidence among PWID in Vietnam.