An almost periodic Ross-Macdonald model with time delay in a patchy environment

An almost periodic multi-patch Ross-Macdonald model with the incubation of virus in hosts and in vectors is investigated in this paper. The existence of the almost periodic disease-free solution and the definition of basic reproduction ratio R(0 )are given. It is shown that the disease will die out when there exists a small invasion and the same dispersal rate in patches if R-0 < 1, while the disease is uniformly persistent if R-0 > 1. At last, numerical simulations illustrate the above results. In addition, a comparison between the almost periodic and periodic models shows that the periodic model may underestimate or overestimate the basic reproduction ratio.