Two Types Of Virus Kinetic Model Studies

Coronavirus Disease 2019(COVID-19)is an infectious disease caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).The pandemic of COVID-19 seriously threatens human life and health,treatments that address the immunopathology of the infection have become a major focus.In this paper,we use differential equations to propose mathematical models for COVID-19 therapy.This paper is divided into four chapters.The first chapter introduces the research significance and current situation of this paper,and the second chapter gives the preliminary knowledge required for the subsequent proof.In the third chapter,we use differential equations to propose a mathematical model for COVID-19 therapy with both defective interfering particles and artificial antibodies.For this model,the basic reproduction number R0 is given and its threshold properties are discussed.We investigate the global asymptotic stability of disease-free equilibrium E0 and infection equilibrium without defective interfering particles E1 by utilizing Lyapunov function and LaSalle's invariance principle.For infection equilibrium with defective interfering particles E2,stability and Hopf bifurcation results are presented.In the forth chapter,we use delay differential equations to propose a mathematical model for COVID-19 therapy with both defective interfering particles and artificial antibodies.For this model,the basic reproduction number R0 is given and its threshold properties are discussed.When R0<1,the disease-free equilibrium E0 is globally asymptotically stable.When R0>1,E0 becomes unstable and the infectious equilibrium without defective interfering particles E1 comes into existence.There exists a positive constant R1 such that E1 is globally asymptotically stable when R1<1<R0.Further,when R1>1,E1 loses its stability and infectious equilibrium with defective interfering particles E2 occurs.There exists a constant R2 such that E2 is asymptotically stable without time delay if 1<R1<R0<R2 and it loses its stability via Hopf bifurcation as the time delay increases.Numerical simulation is also presented to demonstrate the applicability of the theoretical predictions.