LYAPUNOV FUNCTIONALS FOR DELAY DIFFERENTIAL EQUATIONS MODEL OF VIRAL INFECTIONS

• Published in: SIAM journal on applied mathematics Vol. 70; no. 7/8; pp. 2693 - 2708
• Main Authors: HUANG, GANG, TAKEUCHI, YASUHIRO, MA, WANBIAO
• Format: Journal Article
• Language: English
• Published: Philadelphia Society for Industrial and Applied Mathematics 01.01.2010
• Subjects: Differential equations; Disease models; Dynamic modeling; HIV 1; Infection; Infections; Mathematical models; Studies; Viral infections; Virions; Viruses
• ISSN: 0036-1399; 1095-712X
• DOI: 10.1137/090780821

We study global properties of a class of delay differential equations model for virus infections with nonlinear transmissions. Compared with the typical virus infection dynamical model, this model has two important and novel features. To give a more complex and general infection process, a general nonlinear contact rate between target cells and viruses and the removal rate of infected cells are considered, and two constant delays are incorporated into the model, which describe (i) the time needed for a newly infected cell to start producing viruses and (ii) the time needed for a newly produced virus to become infectious (mature), respectively. By the Lyapunov direct method and using the technology of constructing Lyapunov functionals, we establish global asymptotic stability of the infection-free equilibrium and the infected equilibrium. We also discuss the effects of two delays on global dynamical properties by comparing the results with the stability conditions for the model without delays. Further, we generalize this type of Lyapunov functional to the model described by ç-dimensional delay differential equations.