In the UK context, this study’s findings imply that to prevent new cases it is best to focus expensive new treatments for hepatitis C infection on injectors who infrequently share their injecting equipment – patients most likely to be found and recruited via needle exchanges and addiction treatment services.

Key points from summary and commentary
• A simulation model based on what is known about the relevant factors assessed the expected impact on new infections of targeting treatment for hepatitis C infection at injectors at different degrees of risk of spreading the disease.
• Under core assumptions, where fewer than a third of injectors are already infected or fewer than half syringes contaminated, new infections are best averted by treating injectors who frequently risk infection by sharing injecting equipment; when the virus is more widespread, low-risk injectors are the best target.
• These conclusions are dependent on assumptions which may not be realistic or valid in the UK context.