There is considerable interest in determining the impact that increased uptake of treatment for hepatitis C virus (HCV) infection will have on the burden of HCV among people who inject drugs (PWID). An understanding of the size of the population of PWID, rates of injecting cessation and HCV prevalence and incidence within the PWID population is essential for such exercises. However, these parameters are often uncertain. In this paper we review methods for estimating the size of the population of PWID and related parameters, taking into account the uncertainty that exists around data on the natural history of injecting drug use; consider issues in the estimation of HCV prevalence among PWID; and consider the importance of opioid substitution therapy and prisons as settings for the prevention and treatment of HCV infection among PWID. These latter two points are illustrated through examples of ongoing work in England, Scotland and Australia. We conclude that an improved understanding of the size of PWID populations, including current and former PWID and parameters related to injecting drug use and settings where PWID may be reached, is necessary to inform HCV prevention and treatment strategies.
Bibliographical noteFunding Information:
Thank you to James Jansson, Maryam Salehi Alavi and David Wilson for assistance in the development of this paper. SL is supported by an NHMRC Early Career Fellowship (no. 1035149 ). JG is supported by an NHMRC Career Development Fellowship (no. 1035383 ). GJD is supported by NHMRC Practitioner Research Fellowship (no. 1028432 ). LD is supported by an NHMRC Principal Research Fellowship (no. 1041742 ). The National Drug and Alcohol Research Centre at the University of NSW is supported by funding from the Australian Government under the Substance Misuse Prevention and Service Improvements Grant Fund . The Kirby Institute is funded by the Australian Government Department of Health and Ageing . The views expressed in this publication do not necessarily represent the position of the Australia Government. No funding body had any role in study design, the collection, analysis and interpretation of data, the writing of the report, or the decision to submit the article for publication.
© 2015 Elsevier B.V.
- Hepatitis C virus
- People who inject drugs
- Population estimation