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We describe a numerical algorithm for the simulation of the spread of rabies in a spatially distributed fox population. The model considers both territorial and wandering rabid foxes and includes a latent period for the infection. The resulting systems are mixtures of partial differential and integral equations. They are discretized in the space variable by central differences of second order and by the composite trapezoidal rule. In a second step, they are discretized in time by explicit continuous Runge–Kutta methods of fourth order for ordinary and delay differential systems. The results of the numerical calculations are compared for latent periods of fixed and exponentially distributed length and for various proportions of territorial and wandering rabid foxes. The speeds of spread observed in the simulations are compared to spreading speeds obtained by analytic methods and to observed speeds of epizootic frontlines in the European rabies outbreak 1940 to 1980.

We extend our previous work on the spatial spread of fox rabies from one dimension to two dimensions. We consider the case when the latent period has fixed length. We use the method of lines to replace the spatial derivatives and the integral equations with algebraic approximations, then we apply the explicit continuous Runge–Kutta method of fourth order and discrete Runge–Kutta method of third order with six stages to numerically integrate the resulting systems of ordinary and delay differential equations. We discuss and confirm some of the major results we obtained in earlier work. The asymptotic speeds of spread observed in the two-dimensional simulations and in earlier work are discussed and compared with those found in nature.