Table 1.
Symbol | Definition | Sample value used | Parameter range |
CU | Unvaccinated female children | (state variable) | |
AU | Unvaccinated adult women | (state variable) | |
CV | Vaccinated female children | (state variable) | |
AV | Vaccinated adult women | (state variable) | |
IU | Uninfected adult women | (state variable) | |
IV | Infected adult women | (state variable) | |
M | Uninfected men | (state variable) | |
N | Infected men | (state variable) | |
πW | Rate of appearance of new females | 50 per year | 0–100 |
πM | Rate of appearance of new males | 50 per year | 0–100 |
ε | Vaccine immunogenicity in female children | 98% | 75–98% |
Vaccine immunogenicity in adult women | 98% | 75–98% | |
p | Proportion of female children vaccinated | 77% | 0–100% |
Proportion of adult women vaccinated | 40% | 0–100% | |
μC | Mortality rate of children | 1/70 years -1 | 1/140–1/13 |
μ | Leaving rate of adults | 1/10 years-1 | 1/12–1 |
α | Rate of progression of female children to sexually activity | 1/12–1 | |
c | Attentuation constant | 0.15 years-1 | 0–0.3 |
γ | Maximal possible rate of adult vaccination | 0.1 | 0–0.2 |
Rate at which unvaccinated adult women are vaccinated | |||
βN | Probability of infection of a woman by an infected man | 0.00056 | 0–0.00112 |
βM | Probability of infection of a man by an infected woman | 0.0003 | 0–0.0006 |
ψ | Vaccine efficacy | 95% | 85–95% |
Sample parameters were chosen so that (ie the total time between vaccination and leaving was always 13 years), γc-1 = 16.67 (ie the optimum age of vaccination for a perfect vaccine with 100% coverage was 16 years 9 months), βN > βM (ie the transmission probability from men to women was higher than from women to men), the total prevalence without vaccination was 24% and so that the proportion of adult-only vaccination was equal to the proportion of childhood-only vaccination required to eradicate targeted types.