Reinfection with hepatitis C virus following sustained virological response in injection drug users

Background and Aim: Despite that 60-90% of injection drug users (IDUs) are infected with hepatitis C virus (HCV) infection, IDUs are often denied therapy based on concerns of reinfection following treatment. However, there are little data in this regard. We evaluated HCV re-infection following sustained virologic response (SVR) among HCV-infected IDUs having received HCV treatment in a multidisciplinary program. Methods: Following treatment, participants were encouraged to return at follow-up intervals of 1 year and illicit drug use histories were obtained. In those with SVR, HCV RNA testing by PCR was performed to determine if relapse or reinfection occurred. Results: Among 58 receiving HCV treatment between January 2002 and December 2006, 60% (35 of 58) achieved an SVR. Patients were followed for a median of 2.0 years following SVR (range, 0.4-5.0 years), with ongoing illicit and injection drug use reported in 54% (19 of 35) and 46% (16 of 35). Of the 35 with SVR, 28 remained HCV RNA negative during follow-up (80%), with four lost to follow-up and one dying of hepatocellular carcinoma and two cases of reinfection were observed (2 of 35). The rates of reinfection were 3.2 per 100 p-y (95% CI:0.4, 11.5) overall and 5.3 per 100 p-y (95% CI:0.6, 19.0) among those reporting injecting following SVR (n = 16). One of two participants with HCV re-infection spontaneously cleared virus following reinfection. Conclusion: The rate of reinfection following treatment for HCV infection among current and former IDUs engaged in a multidisciplinary program is low.