Using respondent-driven sampling (RDS) we recruited from November 2014 to February 2015 a total of 176 PWID in Zagreb, 255 in Rijeka and 399 in Split. Participants provided biological specimens for HIV and HCV testing and completed a behavioural questionnaire.
The proportion of female PWID ranged from 19.5% in Zagreb to 26.0% in Split. In the month before the survey, 2.5% of PWID in Split, 5.6% in Rijeka and 8.0% in Zagreb reported sharing non-sterile needles and syringes. Many PWID injected opioid substitution therapy (OST) in the month before the survey (57.0% in Zagreb and 57.5% in Split and Rijeka, respectively). Among PWID who had a casual sexual partner in the past 12 months (ranging from 39.2% in Split to 44.4% in Rijeka) condom use was low. Although HIV prevalence was low (0.2% in Rijeka and Zagreb, 0.3% in Split), HCV antibody prevalence was considerable (29.1% in Zagreb, 31.5% in Rijeka, 38.3% in Split). HIV and HCV testing coverage in the past 12 months was insufficient (6.8% and 7.0% in Split; 13.2% and 13.5% in Zagreb; 20.2% and 21.5% in Rijeka, respectively).
We found a low-level HIV epidemic and a sizable HCV epidemic among PWID in Zagreb, Split and Rijeka. Presence of high-risk injecting and sexual behaviours together with inadequate HIV and HCV testing coverage call for development of a comprehensive approach to harm reduction and introduction of needle and syringe exchange programmes in prisons, as well as strengthening sexual health interventions.