Table 1. Model Parameters and Sources.
| Parameter | Symbol | Value at Baseline | Models | Source | |
|---|---|---|---|---|---|
| PWID leaving rate (cessation + death) per year | μ | 0.085a | Both | [19, 20] | |
| Inflow rate of new injectors per year (per 1000 PWID) | θ | 85b | Both | … | |
| Infection rate per year | λ | 0.191c | Both | … | |
| Initial chronic prevalence (%) | … | 40 | Both | [17, 18] | |
| Proportion of new infections that spontaneously clear | α | 0.26 | Both | [18] | |
| PWID vaccinated per 1000 per year | Φv | varied | Vaccine | … | |
| PWID treated per 1000 per year | Φt | varied | Treatment | … | |
| Duration of protection from vaccine (years) | 1/δ | Vaccine | … | ||
| ‘Low efficacy’ vaccine | 5 | ||||
| ‘Moderate’ vaccine | 10 | ||||
| ‘High efficacy’ vaccine | 20 | ||||
| Efficacy of vaccine (%) | 100(1-η) | Vaccine | … | ||
| ‘Low efficacy’ vaccine | 50 | ||||
| ‘Moderate’ vaccine | 70 | ||||
| ‘High efficacy’ vaccine | 90 | ||||
| Proportion of infections cured with treatment | ᴨ | 90 | Treatment | [21] | |
| Duration of treatment (weeks) | 52/ω | 12 | Treatment | [22] | |
a Based on a cessation rate of 7.75% per year, and a PWID death rate of 0.75%
b Set to be 1000μ in order to maintain a total population size of 1000 PWID
c Varied to fit chronic prevalence