HIV Prevalence and Related Behaviors Among People Who Inject Drugs in Iran from 2010 to 2020.

Injection drug use has been the leading route of HIV transmission in Iran. We assessed HIV prevalence, risk behaviors, and uptake of prevention services among people who inject drugs (PWID) in Iran between 2010 and 2020. We also examined the individual and environmental determinants of HIV among PWID. PWID were recruited in major cities across the country in three national bio--behavioral surveillance surveys in 2010, 2014, and 2020. Participants were tested for HIV and interviewed using a behavioral questionnaire. Between 2010 and 2020, the prevalence of HIV (15.1% to 3.5%), receptive needle sharing (25.2% to 3.9%) and unprotected sex (79.4% to 65.2%) decreased. Moreover, uptake of free needle/syringe increased (57.4% to 87.9%), while uptake of free condoms remained relatively stable across the surveys (34.3% to 32.6%). Multivariable analysis for the 2020 survey showed that a history of homelessness, incarceration, and a longer injection career significantly increased the odds of HIV seropositivity. During the past decade, HIV prevalence and drug- and sexual-related risk behaviors decreased among Iranian PWID. However, individual and structural determinants continue to drive HIV among this population. HIV prevention, diagnosis, and treatment among marginalized PWID with a history of homelessness or incarceration and those who inject drugs for a longer period, should be further prioritized in HIV care planning and resource allocation in Iran.