ABSTRACT
Background: Approximately 60% of incident hepatitis C virus (HCV) infections are due to intravenous drug use; therefore, understanding the socio-demographics of people who inject drugs (PWID) is necessary to achieve HCV elimination. Methods: In this prospective cohort study of PWID, we determined patients' baseline HCV antibody, hepatitis B virus (HBV), and HIV serological status. HCV antibody- negative (anti-HCV-negative) cases were followed for seroconversion (median 17 mo with q3m testing) as part of a larger study to develop a vaccine for HCV. An interviewer-administered baseline questionnaire completed with all patients evaluated socio-demographic and clinical characteristics. Results: We tested 257 PWID (median age 40 [range 49-31]y, 81% men, 63% Caucasian, 28% Indigenous). Of these, 28% were positive for HCV antibodies (anti-HCV-positive) (median age 42 [range 49-36]y, 74% men, 69% Caucasian, 29% Indigenous). Compared with anti-HCV-negative PWID, anti-HCV-positive PWID reported injecting more morphine and hydromorphone, using more hydromorphone via non-injection routes, and were more likely to be enrolled in methadone programs. More than 60% reported previous HCV testing, but recent testing (<2 y) was more frequent in the anti-HCV-negative group (p = 0.03). All were HBV negative, but more than 50% of the anti-HCV-positive group had anti-HBs titres more than 10 IU/L compared with 35% of the anti-HCV-negative group (p = 0.01), and 3 of 257 were HIV positive (1 co-infected with HCV-HIV). Conclusions: In this prospective study, differences in age, timing of HCV testing and risk behaviours were found between anti-HCV-positive and anti-HCV-negative groups.
