Table 2 Cross-setting and country-specific parameters
From: The case for a universal hepatitis C vaccine to achieve hepatitis C elimination
Vaccine parameters | ||
Efficacy | 75% | Assumed; tested in sensitivity analysis |
Average duration of protection | 10 years | Assumed; tested in sensitivity analysis |
Costs | ||
Antibody tests | US$1.1 | WHO estimate |
RNA tests | US$20 | WHO estimate |
Antibody test positivity rate among PWID | 1/PWID prevalence | Assumes frequency-based testing for PWID |
Antibody test positivity rate among the general population | 2/general population prevalence | Assumes general population testing populations are slightly targeted. |
Treatment | US$150 | WHO estimate, assuming generic pricings are available. Tested in the sensitivity analysis |
Vaccination | US$200 | Assumed; Tested in sensitivity analysis |
Cost discounting | 3% per annum | WHO recommendation [16] |
Hepatitis C-related parameters | ||
Relative reduction in infection risk when covered by harm reduction | 79% | Turner et al. [17], combined needle and syringe and opioid substitution therapy programmes. |
Spontaneous clearance | 26% | Micallef et al. [12] |
Treatment effectiveness | 95% | |
Country-specific parameters: for specific country estimates, see Additional file 1: Appendix A—Table S1 | ||
Total population size | UN Population Division [13]; 15–64 years (2016). | |
Proportion of the population who inject drugs | Degenhardt et al. [9]. For countries without estimates, WHO region values were applied [22]. | |
Additional injecting-related mortality | Mathers et al. systematic review [23] (0.0235 per year) | |
Epidemic type | Individual countries were classified as concentrated or mixed: epidemics were classified as mixed if the country was not in a WHO high income classification AND the total number of people living with hepatitis C was > 5 times the total number of estimated hepatitis C-infected PWID. This classification was used as without modelling transmission among the general population in these settings, the model was unable to produce the correct number of people living with hepatitis C based on injecting drug use-related transmission alone. Countries with general community transmission according to the above definition were classified as mixed rather than generalised (at the national level), since their PWID populations had significantly higher hepatitis C prevalence than the general community, and so the epidemics were assumed to have a concentrated component. | |
Prevalence among PWID | Degenhardt et al. [9] For countries without estimates, population-weighted averages were calculated for each WHO region and applied. | |
Prevalence in general population | Blach et al. [14] and Gower et al. [15] For countries without estimates, population-weighted averages were calculated for each WHO region and applied. | |
Healthcare system coverage | Assumed to be 80% (with 70% and 90% used to derive uncertainty bounds). This parameter defines the coverage of testing / vaccination that could be achieved, and is used to derive uncertainty bounds for outcomes. | |
Harm reduction coverage | Assumes that the status-quo is maintained for each country, with harm reduction scale-up tested in the sensitivity analysis. | |
Staffing cost per interaction (testing+/−vaccination and treatment) | Estimated based on 2 h of provider time for interaction and any laboratory work. Average salary calculated as the population-weighted per capita gross domestic product (GDP) [24]. Assumes providers work 7 h per day, 5 days per week and 45 weeks per year. Tested in sensitivity analysis. | |