Delay effect in a model for virus replication.

Abstract

As biology becomes more quantitative, it appears that the increasing use of mathematics in this area is inevitable. In 1996, Nowak & Bangham (1996, Science 272, 74-79) proposed three mathematical models to explore the relation between antiviral immune responses, virus load, and virus diversity. In this paper we investigate the delay effect in a model which considers the interaction between a replicating virus and host cells. We assume that there is a finite time lag between infection of a cell and the emission of viral particles. Even with the introduction of this delay, the steady states of the model--as suggested by Nowak & Bangham--remain stable. The result also gives a condition for how the parameter values should be chosen when analysing clinical data so that the model remains tenable.