The costs and benefits of a prison needle and syringe program in Australia, 2025–30: a modelling study

Abstract

Objectives

To estimate and compare the costs and benefits of introducing a prison needle and syringe program in all Australian prisons.

Study design

Stochastic compartmental modelling study.

Setting

All Australian prisons, 1 January 2010 to 31 December 2030.

Intervention

Introduction of a prison needle and syringe program in all Australian prisons during 1 January 2025 – 1 January 2027, with the aim of covering 50% of people who inject drugs in prison by 1 January 2030.

Main outcome measures

Projected new hepatitis C virus (HCV) infections and hospitalisations with injection-related bacterial and fungal infections in prisons, with and without the needle and syringe program; costs of the program; savings in treatment costs for HCV and injection-related bacterial and fungal infections; benefit–cost ratio of the program.

Results

In the base scenario (no prison needle and syringe program), the projected number of new HCV infections during 2025–2030 was 2932 (uncertainty interval [UI], 2394–3507) and the projected number of hospitalisations with injection-related bacterial and fungal infections was 3110 (UI, 2596–3654). With the prison needle and syringe program, it was projected that 894 (UI 880–912) new HCV infections (30%; UI, 26–37%) and 522 (UI, 509–532) hospitalisations with injection-related bacterial and fungal infections (17%; UI, 15–20%) would be averted; the incidence of new HCV infections would be reduced from 3.1 (UI, 2.5–3.7) to 1.3 (UI, 1.0–1.7) per 100 person-years among people who inject drugs in prison. The estimated cost of the program was $12.2 million (UI, $7.6–22.2 million), and the saved care costs for HCV and injection-related infections were $31.7 million (UI, $29.3–34.6 million), yielding a benefit–cost ratio of 2.6 (UI, 1.4–4.1). The benefit–cost ratio was also greater than one for scenarios in which the assumptions and base values for several parameters were varied.

Conclusions

Each dollar spent on a needle and syringe program in Australian prisons could save $2.60 in treatment costs for HCV and other injection-related infections.