HIV prevalence and related risk behaviours among female partners of male injecting drugs users in Iran: results of a bio-behavioural survey, 2010

OBJECTIVE: Sexual partners of injecting drug users (IDUs) are at high risk of HIV infection, yet data for such populations are scarce worldwide, particularly in the Middle East and North African region. This study measured and compared the prevalence of HIV, hepatitis C (HCV), hepatitis B (HBV) and related behavioural factors in male IDUs (MIDUs), their main female sexual partners who were also injecting drug users (FIDUPs) and their main non-injecting female partners (FNIDUPs). METHOD: Using convenience sampling, MIDUs were recruited at drop-in health centres in three cities (Tehran, Mashhad and Shiraz), who in turn recruited their main female partners. Behavioural data were collected using a standard questionnaire, and blood samples were drawn for HIV and HCV antibody testing and HBV surface antigen. RESULTS: HIV prevalence was 9.4% (95% CI 2.96% to 26.2%) among MIDUs (n=226), 7.7% (95% CI 1.9% to 26.3%) among FIDUPs (n=42) and 2.8% (95% CI 0.65% to 11.3%) among FNIDUPs (n=184). HCV prevalence was 38.6% (95% CI 20.3% to 60.7%) among MIDUs, 36.6% (95% CI 13.6% to 67.9%) among FIDUPs and 8.4% (95% CI 5.67% to 12.4%) among FNIDUPs. HBV surface antigen prevalence was 3.6% (95% CI 1.5% to 8.3%), 7.3% (95% CI 1.9% to 24.8%) and 1.1% (95% CI 0.3% to 4.7%), respectively. Among MIDUs, 19.5% (95% CI 3.4% to 62.2%) had a history of sexual contact with other men. Mean age at first sexual contact in MIDUs was 19.2 years (95% CI 18.6 to 25.2) and in FIDUPs and FNIDUPs 16.4 years (95% CI 14.1 to 22.1) and 18.2 years (95% CI 15.7 to 23.1), respectively. FIDUPs and FNIDUPs had a higher mean number of sexual partners (other than their main partner) in the previous month than MIDUs (5.5 (95% CI 0 to 14.1) and 2.5 (95% CI 1.1 to 4) vs 1.3 (95% CI 0.37 to 2.2), respectively). FIDUPs tended to use drugs before or during sex with their main and casual partners more often than MIDUs (with main partner: 69% (95% CI 41.5% to 87.5%) vs 54.4% (95% CI 27% to 79.4%), respectively, and with casual partners: 47.6% (95% CI 13.1% to 84.6%) vs 34.1% (95% CI 10% to 70.6%), respectively); however, the differences were not statistically significant. CONCLUSIONS: Female partners of MIDUs in Iran and elsewhere are an under studied group. The high rate of HIV, HCV and HBV infection among females who are partners of MIDUs points to the necessity of appropriate injection and sexual risk reduction interventions among this group, to prevent acquisition of HIV, HCV and HBV and their onward transmission to other male partners.