Table 1 Parameter definitions for the COVID-19 epidemics
Parameter | Definitions | |
c(t) | c0 | Contact rate at the initial time |
cb | Minimum contact rate under the current control strategies | |
r1 | Exponential decreasing rate of contact rate | |
c | Constant contact rate | |
β | Probability of infected individual’s transmission per contact | |
q(t) | q0 | Quarantined rate of exposed individuals at the initial time |
qm | Maximum quarantined rate of exposed individuals under the current control strategies | |
r2 | Exponential increasing rate of quarantined rate of exposed individuals | |
q | Constant quarantined rate of exposed individuals | |
ϑ | Quarantined rate of susceptible individuals to the suspected class | |
βA | Probability of asymptomatic individual’s transmission per contact | |
βH | Probability of quarantined infected individual’s transmission per contact | |
ρ | Proportion of symptomatic infection | |
σ | Transition rate of exposed individuals to the infected class | |
λ | Rate at which the quarantined uninfected contacts were released into the wider community | |
δI(t) | δI0 | Initial diagnosis rate of infected individuals |
δIf | Fastest diagnosis rate of infected individuals | |
r3 | Exponential increasing rate of diagnosis rate of infected individuals | |
δI | Constant diagnosis rate of infected individuals | |
δT(t) | δT0 | Initial diagnosis rate of quarantined individuals |
δTf | Fastest diagnosis rate of quarantined individuals | |
r4 | Exponential increasing rate of diagnosis rate of quarantined individuals | |
δT | Constant diagnosis rate of quarantined individuals | |
ω | Confirmation ratio of quarantined exposed individuals | |
θ | Rate at which the confirmed infected individuals were hospitalized | |
γA | Recovery rate of asymptomatic infected individuals | |
γ1 | Recovery rate of confirmed infected individuals without hospitalization | |
γ2 | Recovery rate of hospitalized infected individuals | |
α | Disease-induced death rate of infected individuals | |
α1 | Disease-induced death rate of confirmed infected individuals without hospitalization | |
α2 | Disease-induced death rate of hospitalized infected individuals | |
Hc(t) | H0 | The number of available hospital beds at the initial time |
Hf | Maximum capacity of hospital beds | |
rh | Exponential increasing rate of hospital beds | |
Initial values | Definitions | |
S(0) | Initial susceptible population | |
E(0) | Initial exposed population | |
I(0) | Initial infected population | |
A(0) | Initial asymptomatic population | |
T(0) | Initial suspected population | |
Sq(0) | Initial quarantined susceptible population | |
H1(0) | Initial confirmed infected population without hospitalization | |
H2(0) | Initial hospitalized infected population | |
R(0) | Initial recovered population | |