Dynamics of epidemics in homogeneous/heterogeneous populations and the spreading of multiple inter-related infectious diseases: Constant-sign periodic solutions for the discrete model

摘要

We consider the following model that describes the dynamics of epidemics in homogeneous/heterogeneous populations as well as the spreading of multiple inter-related infectious diseases: [GRAPHICS] Our aim is to establish criteria such that the above system has one or multiple constant-sign periodic solutions (u(1), u(2), . . . , u(n)), i.e., for each 1 <= i <= n, u(i) is periodic and theta(i)u(i) >= 0 where theta(i) is an element of {1, -1} is fixed. Examples are also included to illustrate the results obtained. (c) 2006 Elsevier Ltd. All rights reserved.