Injecting drug users, sex workers and men who have sex with men: a national cross-sectional study to develop a framework and prevalence estimates for national HIV/AIDS programmes in the Republic of Serbia

OBJECTIVE: The aim of this study was to develop a framework and best estimates of prevalence for the most at risk populations (MARPs) for HIV/AIDS to include sex workers (SW), men who have sex with men (MSM) and injecting drug users (IDUs) in order to evaluate national HIV/AIDS programmatic targets across the Republic of Serbia. DESIGN: A national, cross-sectional study and direct enumeration, multiplier and benchmark methods with integrated bio-behavioural surveys, capture/recapture and methods with Wald and Clopper-Pearson CIs were used. SETTING: This study was carried out in the three largest cities and main regions of Serbia, the capital city, Belgrade, (population 1 639 121 persons), the Vojvodina region with main city Novi Sad (population 335 701) and the rest of Serbia with main city Nis (population 257 867). PARTICIPANTS: A total of 1301 respondents from the defined MARPs completed the survey in the 2009/2010 period across the three cities. PRIMARY OUTCOME MEASURES: Estimates of the hidden numbers at risk of HIV/AIDS. RESULTS: It was estimated that there were 1775–6027 SW between 18 and 49 years in Serbia in 2009. For MSM, national estimates for 2009 ranged from 20 789 to 90 104 individuals aged between 20 and 49 years. For IDU, a possible range of 12 682–48 083 individuals aged between 15 and 59 years in 2009 was estimated. CONCLUSIONS: For service planning across Central and Eastern Europe, it is important to highlight how credible estimates can be achieved and compared with numbers within HIV/AIDS-prevention programmes. Within needle exchange programmes, only 5.4–20.5% of the estimated population was observed and this proportion was lower within methadone treatment data. Results have implications for future IDU treatment and HIV incidence and spread across all populations at risk.