Lattice three-species models of the spatial spread of rabies among foxes

Lattice models describing the spatial spread of rabies among foxes are stud ied. In these models, the fox population is divided into three-species: sus ceptible (S), infected or incubating (I), and infectious or rabid (R). They are based on the fact that susceptible and incubating foxes are territoria l while rabid foxes have lost their sense of direction and move erratically . Two different models are investigated: a one-dimensional coupled-map latt ice model, and a two-dimensional automata network model. Both models take i nto account the short-range character of the infection process and the diff usive motion of rabid foxes. Numerical simulations show how the spatial dis tribution of rabies, and the speed of propagation of the epizootic front de pend upon the carrying capacity of the environment and diffusion of rabid f oxes out of their territory.