Skip to main content

The effects of needle-sharing and opioid substitution therapy on incidence of hepatitis C virus infection and reinfection in people who inject drugs

  • C. K. AITKEN (a1) (a2), P. A. AGIUS (a1), P. G. HIGGS (a1) (a3) (a4), M. A. STOOVÉ (a1) (a2), D. S. BOWDEN (a5) and P. M. DIETZE (a1) (a2)...

Although high hepatitis C virus (HCV) prevalence has been observed in people who inject drugs (PWID) for decades, research suggests incidence is falling. We examined whether PWIDs’ use of opioid substitution therapy (OST) and their needle-and-syringe sharing behaviour explained HCV incidence. We assessed HCV incidence in 235 PWID in Melbourne, Australia, and performed discrete-time survival with needle-sharing and OST status as independent variables. HCV infection, reinfection and combined infection/reinfection incidences were 7·6 [95% confidence interval (CI) 4·8–11·9], 12·4 (95% CI 9·1–17·0) and 9·7 (95% CI 7·4–12·6) per 100 person-years, respectively. Needle-sharing was significantly associated with higher incidence of naive HCV infection [hazard ratio (HR) 4·9, 95% CI 1·3–17·7] but not reinfection (HR 1·85, 95% CI 0·79–4·32); however, a cross-model test suggested this difference was sample specific. Past month use of OST had non-significant protective effects against naive HCV infection and reinfection. Our data confirm previous evidence of greatly reduced HCV incidence in PWID, but not the significant protective effect of OST on HCV incidence detected in recent studies. Our findings reinforce the need for greater access to HCV testing and prevention services to accelerate the decline in incidence, and HCV treatment, management and support to limit reinfection.

Corresponding author
*Author for correspondence: Dr C. K. Aitken, Centre for Population Health, Burnet Institute, 85 Commercial Rd, Melbourne, 3004, Australia. (Email:
Hide All
1. Rodger, AJ, et al. Assessment of long term outcomes of community-acquired hepatitis C infection in a cohort with sera stored from 1971–1975. Hepatology 2000; 32: 582587.
2. Maher, L, et al. Incidence and risk factors for hepatitis C seroconversion in injecting drug users in Australia. Addiction 2006; 101: 14991508.
3. Grebely, J, et al. Reinfection with hepatitis C virus following sustained virological response in injection drug users. Journal of Gastroenterology and Hepatology 2010; 25: 12811284.
4. Bell, J, et al. Hepatitis C in intravenous drug users. Medical Journal of Australia 1990; 153: 274276.
5. Iversen, J, et al. Reduction in HCV incidence among injection drug users attending needle and syringe programs in Australia: a linkage study. American Journal of Public Health 2013; 103: 14361444.
6. Dietze, P, Fitzgerald, J. Interpreting changes in heroin supply in Melbourne: droughts, gluts or cycles? Drug and Alcohol Review 2002; 21: 295303.
7. Turning Point Alcohol and Drug Centre. AODstats Opioid replacement therapy. ( Accessed 21 November 2014.
8. Turning Point Alcohol and Drug Centre. AODstats: NSP distributed – total program. ( Accessed 21 November 2014.
9. Higgs, P, Maher, L. Older injectors: an emerging and under-recognised public health issue. Drug and Alcohol Review 2010; 29: 233234.
10. White, B, et al. Opioid substitution treatment protects against hepatitis C virus acquisition in people who inject drugs: The HITS-c study. Medical Journal of Australia 2014; 201: 326329.
11. Nolan, S, et al. The impact of methadone maintenance therapy on hepatitis C incidence among illicit drug users. Addiction 2014; 109:20532059.
12. Grebely, J, et al. Declining incidence of hepatitis C virus infection among people who inject drugs in a Canadian setting, 1996–2012. PLoS ONE 2014; 9: e97726.
13. Turner, KM, et al. The impact of needle and syringe provision and opiate substitution therapy on the incidence of hepatitis C virus in injecting drug users: pooling of UK evidence. Addiction 2011; 106: 19781988.
14. Horyniak, D, et al. Establishing the Melbourne Injecting Drug User Cohort Study (MIX): rationale, methods, and baseline and twelve-month follow-up results. Harm Reduction Journal 2013; 10: 11.
15. Heckathorn, DD. Respondent-driven sampling: a new approach to the study of hidden populations. Social Problems 1997; 44: 174199.
16. Aitken, CK, et al. Molecular epidemiology of hepatitis C virus in a social network of injection drug users. Journal of Infectious Diseases 2004; 190: 15861595.
17. Fry, CL, et al. The ethics of paying drug users who participate in research: a review and practical recommendations. Journal of Empirical Research on Human Research Ethics 2006; 1: 2136.
18. Allison, PD. Event History and Survial Analysis, 2nd edn. Thousand Oaks, California, USA: Sage, 2014.
19. Weesie, J. Seemingly unrelated estimation and the cluster-adjusted sandwich estimator. Stata Technical Bulletin 52: 3447. Reprinted in Stata Technical Bulletin Reprints 9, pp. 231–248. College Station, TX: Stata Press.
20. Huber, PJ. The behavior of maximum likelihood estimates under nonstandard conditions. Ffifth Berkeley Symposium on Mathematical Statistics and Probability. Berkeley, CA: University of California Press, 1967, pp. 221233.
21. StataCorp. Stata Statistical Software: Release 13. College Station, Texas, USA: StataCorp LP, 2013.
22. Aitken, CK, et al. High incidence of hepatitis C virus reinfection in a cohort of injecting drug users. Hepatology 2008; 48: 17461752.
23. McDonald, SA, et al. Examination of the risk of reinfection with hepatitis C among injecting drug users who have been tested in Glasgow. International Journal on Drug Policy 2012; 23: 353357.
24. Hagan, H, et al. A systematic review and meta-analysis of interventions to prevent hepatitis C virus infection in people who inject drugs. Journal of Infectious Diseases 2011; 204: 7483.
25. Des Jarlais, DC. Commentary on Zhou et al. (2015): Research on methadone maintenance treatment (MMT) as prevention for HCV infection – MMT is not a single variable. Addiction 2015; 110: 803804.
Recommend this journal

Email your librarian or administrator to recommend adding this journal to your organisation's collection.

Epidemiology & Infection
  • ISSN: 0950-2688
  • EISSN: 1469-4409
  • URL: /core/journals/epidemiology-and-infection
Please enter your name
Please enter a valid email address
Who would you like to send this to? *



Altmetric attention score

Full text views

Total number of HTML views: 0
Total number of PDF views: 0 *
Loading metrics...

Abstract views

Total abstract views: 0 *
Loading metrics...

* Views captured on Cambridge Core between <date>. This data will be updated every 24 hours.

Usage data cannot currently be displayed