The total number of male injecting drug users (IDUs) in Eastern Nepal is estimated to be about 2200 from more than 150 locations. This is a much smaller number than usually quoted by local NGOs in Eastern Nepal. Prevalence of HIV among male IDUs is 35 percent. HIV prevalence differs significantly by the districts included in the sample. Those who inject in other places, mostly in the border towns of India, have higher risk of HIV infection.

The main objective of the study was to estimate the prevalence of HIV among IDUs and assess their role in the transmission of HIV in Eastern Nepal. Since these people function as a bridging population to transmit HIV to the general population, it was necessary to understand the role of risky behaviors in the transmission of HIV. The study was conducted in Jhapa, Morang and Sunsari districts.