Theory and Modern Applications
Table 1 Details of symbols of SVELITR model (6)
From: Transmissibility of epidemic diseases caused by delay with local proportional fractional derivative
Symbol | Description | Units (population = ’000s & time = days) |
|---|---|---|
ℵ(t) | Total population | Population/day |
S(t) | No. of susceptible individuals at any time t | Population/day |
V(t) | No. of vaccinated individuals at any time t | Population/day |
E(t) | No. of individuals exposed to the infection at any time t | Population/day |
L(t) | No. of individuals latent to the infection at any time t | Population/day |
I(t) | No. of infected individuals at any time t | Population/day |
\(T_{r} ( t )\) | No. of treated individuals at any time t | Population/day |
R(t) | No. of recovered individuals at any time t | Population/year |
Ï„ | Time delay | days |
α | Order of fractional derivative | dimensionless |
r | Rate intrinsic growth of susceptible individuals | Individuals/(individuals × year) |
k | Surviving capacity of susceptible individuals | Individuals/(area × year) |
μ | Rate of vaccinated susceptible | Individuals/(individuals × year) |
β | Contact rate of susceptible with infected | Individuals/(individuals × year) |
σ | Rate of susceptible exposed to infection | Individuals/(individuals × year) |
γ | Rate of exposed latent to infection | Individuals/(individuals × year) |
ψ | Recovery rate of the treated individuals | Individuals/(individuals × year) |
\(\eta _{ ( \bullet )}\) | Natural death rate of individuals in a compartment | Individuals/(individuals × year) |
\(\rho _{ ( \bullet )}\) | Rate of treated exposed, latent, or infected individuals | Individuals/(individuals × year) |