Prevalence and Incidence of HCV Infection among Vietnam Heroin Users with Recent Onset of Injection

HCV infection continues to spread at an alarming rate among IDU populations. The available evidence suggests that HCV is acquired relatively quickly following onset of injection. However, there are few prospective studies of HCV acquisition, particularly among IDU populations in resource-poor settings. A sample of young male heroin injectors with recent onset of injection (<4 years) was recruited in Hanoi, Vietnam for a prospective assessment of the early course of injection (n?=?179). Both behavioral and biological assessments (including detailed retrospective assessment of injection initiation) were conducted at baseline and repeated at 6-month intervals for a period of 16 months. Variables associated with HCV infection (p value?p value?=?0.0005). In multivariate logistic regression analysis, increasing age, incarceration in a drug detention facility (OR?=?2.54; 95%CI 1.05, 6.15), and time since first injection remained significantly associated with HCV infection. Use of injection as primary mode of administration (OR?=?2.56; 95%CI 0.98, 6.69) achieved marginal significance. After 16 months of follow-up, the incidence rate of HCV was 23.35 per 100 person-years and the mean time between first injection and first positive HCV test was 1.2 years. HCV is acquired much more rapidly among new injector populations than previously recognized, demonstrating the need for early behavioral intervention among new heroin-user populations. Particularly critical are interventions that target new heroin user populations, including interventions that improve understanding of viral transmission dynamics, that promote alternative strategies for drug sharing, and that delay initiation of injection.