Table 1.
Nomenclature.
| symbol | description |
|---|---|
| r | births per year |
| f | maturity rate |
| d1 | juvenile death rate |
| d2 | adult death rate |
| ks,1 | juvenile death rate from varicella (no vaccine) |
| ks,2 | adult death rate from varicella (no vaccine) |
| kv,1 | varicella mortality of vaccinated juveniles |
| kv,2 | varicella mortality of vaccinated adults |
| σ | 1/duration of incubation period |
| δs | 1/duration of infectious period (no vaccine) |
| δv | 1/duration of infectious period if vaccinated |
| β1 | transmission rate—juveniles to juveniles |
| β2 | transmission rate—adults to adults, adults to juveniles and juveniles to adults |
| v | vaccination probability |
| p | probability of primary failure |
| φ | probability of temporary protection |
| ε | probability of becoming infected if vaccinated |
| b | probability that immunity will be ‘boosted’ if exposed to varicella while vaccine protected |
| ρ | relative infectiousness of breakthrough varicella |
| ψ | waning rate (year−1) |
| λ1 | forces of infection in juveniles |
| λ2 | forces of infection in adults |
| pIJ | infection probability for juveniles |
| pBJ | breakthrough probability for juveniles |
| pIA | infection probability for adults |
| pBA | breakthrough probability for adults |
| CIJ | total expected costs of infection per case in juveniles |
| CIA | total expected costs of infection per case in adults |
| CBJ | total expected costs of breakthrough infection in juveniles |
| CBA | total expected costs of breakthrough infection in adults |
| Cv | vaccination cost |
| DR | disutility of vaccine refusal (expected cost to individuals who do not receive the vaccine) |
| DV | disutility of vaccination (expected cost to vaccinated individuals) |
| Dave | average disutility to the society (expected societal cost per person) |
| VN | Nash equilibrium vaccination coverage |