ABSTRACT
This work considers a new stochastic mathematical model for the transmission dynamics of the coronavirusCOVID-19 by providing the healthy compartment together with the quarantine/isolation compartment. In the deterministic model, global stability conditions of the disease-free equilibrium E0 and the endemic equilibrium E*are derived in terms of the threshold quantity Rd0. Based on the chaotic behavior, we develop and analyze a fourdimensional stochastic COVID-19 epidemic model. Uniqueness, boundedness, and positiveness of the proposed stochastic model are investigated in a biologically feasible region. In terms of the stochastic basic reproduction number Rs0 of the stochastic model, extinction and persistence of the COVID-19 disease are derived. Our theoretical findings are supported by some numerical simulations. The sensitivity of the model with respect to the parameters involved in the system is studied to investigate the most sensitive parameter towards the highest number of infected individuals. We confirm the stability analysis by showing the elasticity of Rs 0 with respect to the variation of each parameter. We present real data of a case study with the first wave of the COVID-19 epidemic in the United Kingdom. We compare our numerical results with the real data. © 2023 L&H Scientific Publishing, LLC. All rights reserved.
ABSTRACT
In this paper, a new mathematical model that describes the dynamics of the within-host COVID-19 epidemic is formulated. We show the stochastic dynamics of Target-Latent-Infected-Virus free within the human body with discrete delay and noise. Positivity and uniqueness of the solutions are established. Our study shows the extinction and persistence of the disease inside the human body through the stability analysis of the disease-free equilibrium [Formula: see text] and the endemic equilibrium [Formula: see text], respectively. Moreover, we show the impact of delay tactics and noise on the extinction of the disease. The most interesting result is even if the deterministic system is inevitably pandemic at a specific point, extinction will become possible in the stochastic version of our model.