Per-event probability of hepatitis C infection during sharing of injecting equipment

Lies Boelen; Suzy Teutsch; David P Wilson; Kate Dolan; Greg J Dore; Andrew R Lloyd; Fabio Luciani; HITS investigators

doi:10.1371/journal.pone.0100749

Per-event probability of hepatitis C infection during sharing of injecting equipment

PLoS One. 2014 Jul 7;9(7):e100749. doi: 10.1371/journal.pone.0100749. eCollection 2014.

Authors

Lies Boelen¹, Suzy Teutsch², David P Wilson³, Kate Dolan⁴, Greg J Dore³, Andrew R Lloyd², Fabio Luciani²; HITS investigators

Collaborators

HITS investigators:
Andrew Lloyd, Kate Dolan, Paul Haber, William Rawlinson, Carla Treloar, Greg Dore, Lisa Maher, Fabio Luciani

Affiliations

¹ Inflammation and Infection Research Centre, School of Medical Sciences, The University of New South Wales, Sydney, Australia; Section of Immunology, School of Medicine, Imperial College, London, United Kingdom.
² Inflammation and Infection Research Centre, School of Medical Sciences, The University of New South Wales, Sydney, Australia.
³ The Kirby Institute, The University of New South Wales, Sydney, Australia.
⁴ National Drug and Alcohol Research Centre, The University of New South Wales, Sydney, Australia.

Abstract

Background: Shared injecting apparatus during drug use is the premier risk factor for hepatitis C virus (HCV) transmission.

Aims: To estimate the per-event probability of HCV infection during a sharing event, and the transmission probability of HCV from contaminated injecting apparatus.

Methods: Estimates were obtained using a maximum likelihood method with estimated IDU and sharing events obtained from behavioural data.

Settings: Cohort study in multiple correction centres in New South Wales, Australia.

Participants: Subjects (N = 500) with a lifetime history of injecting drug use (IDU) who were followed up between 2005 and 2012. During follow-up, interviews for risk behaviours were taken and blood sampling (HCV-antibody and RNA testing) was performed.

Measurements: Self-reported frequencies of injecting drugs and sharing events, as well as other risk behaviours and details on the nature of injecting events.

Findings: The best estimate of the per-event probability of infection was 0.57% (CI: 0.32-1.05%). A sensitivity analysis on the likely effect of under-reporting of sharing of the injecting apparatus indicated that the per event infection probability may be as low as 0.17% (95% CI: 0.11%-0.25%). The transmission probability was similarly shown to range up to 6%, dependent on the presumed prevalence of the virus in injecting equipment.

Conclusions: The transmission probability of HCV during a sharing event is small. Hence, strategies to reduce the frequency and sharing of injecting equipment are required, as well as interventions focused on decreasing the per event risk.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adolescent
Adult
Female
Hepatitis C / transmission*
Humans
Male
Needle Sharing / adverse effects*
Probability
Self Report
Substance Abuse, Intravenous / virology
Young Adult

Grants and funding

This work was supported by the National Health and Medical Research Council of Australia (NHMRC) Program grant (No. 510488), and by a grant from the Australian Centre for HIV and Hepatitis Research (ACH2). The HITS-p cohort was supported by an NHMRC Partnership Grant (No. 1016351). FL was supported by a NHMRC Early Career Fellowship (No. 510428) and AL by a NHMRC Practitioner Fellowship (No. 510246). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.