Abstract:The prevalence, risk factors, and prevention opportunities of hepatitis A, B, C and HIV infection was studied in injecting drug users (IDUs) in comparison with non-injecting drug users (n-IDUs) in Uppsala County, Sweden.The seroprevalence among IDUs were 0.7% for HIV, 19% for HAV, 26% for HBV and 63% for HCV. For hepatitis C, the seroprevalence was directly related to the number of years of injections. No cases of HIV were found among the nIDUs and the seroprevalence rate was significantly lower for HBV and HCV, 6 and 2%, respectively. In contrast, the anti-HAV antibody seroprevalence was not significantly different between n-IDUs and IDUs (27% vs 19%, p