From: Impact of viral drift on vaccination dynamics and patterns of seasonal influenza
Parameter | Description | Value (range) |
---|---|---|
q s ,q v ,q r | Fraction of individuals receiving vaccination | 0 - 1 |
σ | Vaccine efficacy | 0.6 – 0.95 |
μ | Fraction of population vaccinated | Variable |
m 1 | Number of seasons that the protection acquired from natural infection lasts | 2 - 8 seasons |
m 2 | Number of seasons that the protection acquired from vaccination lasts | 2 - 4 seasons |
γ | Recovery rate from infection | 0.2 day -1 |
ϵ j | Amplitude of seasonal fluctuation | 0.85 |
α | Age since last infection | Variable |
i = 0, 1, ⋯, m 2 - 1 | Baseline transmission rates of infection for susceptible, vaccinated, and recovered individuals, respectively | β s  = 150/N year -1 (N: total population size) |
| Baseline transmission rates of infection for previously vaccinated and recovered individuals, respectively, who also received vaccine for the current season | Variable |
κ s (t) = β s  · P s (t) | Transmission rate of infection for susceptible class | Variable |
| Transmission rate of infection for newly vaccinated from susceptible class | Variable |
| Transmission rate of infection for previously vaccinated individuals who received their last vaccine i seasons ago | Variable |
i = 1, 2, ⋯, m 2 - 1 | ||
| Transmission rate of infection for previously vaccinated individuals who also received vaccine for the current season | Variable |
κ r (t, a) = β r (a) · P r (t) | Transmission rate of infection for recovered individuals with the recovery age α since last infection | Variable |
| Transmission rate of infection for recovered individuals who received vaccine for the current season | Variable |