The impact of an HIV prevention intervention for injecting drug users in Svetlogorsk, Belarus: model predictions

Abstract

Background: From the mid-1990s there has been a rapid spread of HIV infection amongst injecting drug users (IDUs) in Svetlogorsk, Belarus. In 1997, when the IDU HIV prevalence had reached 74%, two needle and syringe exchange points (NEPs) were established in the town. These interventions have been operating since then, with some interruptions due to a lack of funding 1998. Methods: This article presents a deterministic epidemiological model ‘ IDU 2.4’ that simulates the transmission of HIV among IDUs sharing injecting equipment, and between IDUs and their sexual partners. The model incorporates the impact of the interrupted distribution of clean syringes and condoms, is validated against data from Svetlogorsk, and is used to estimate the impact of the intervention on HIV transmission. Results: The model predicts that between 1997 and 2000 the intervention averted 414 HIV infections in Svetlogorsk (95% CI, 180–690) and caused a 6.5% decrease in IDU HIV prevalence compared to if there had been no intervention. The analysis also suggests that the gap in funding between 1998 and 1999 resulted in a 35% reduction in the number of HIV infections averted among IDUs during that period, and that the IDU HIV prevalence is 3% higher in 2000 (95% CI, 1.9–4.6%) than if there had been no gap in funding. Conclusions: Even though the HIV prevalence and incidence amongst the IDUs remained high, the findings suggest that the intervention had an important affect on HIV transmission in Svetlogorsk, Belarus. The findings reinforce the importance of strengthening existing projects and replicating similar projects in the region, and highlight the detrimental impact of gaps in intervention funding.