In this paper, to study nonlinear dynamics of a reaction-diffusion equation with delay, the authors give numerical simulations for 1D and 2D cases. They obtain that homogeneous in space solutions can manifest time oscillations with period doubling bifurcations and transition to chaos. Transition between two regions with homogeneous oscillations is provided by quasi-waves, propagating solutions without regular structure and often with complex aperiodic oscillations. Moreover, the dynamics of space-dependent solutions is described by a combination of various waves, e.g., bistable, monostable, periodic and quasi-waves. \par Overall these results are interesting and their study suggests a richness of spatiotemporal patterns of infection dynamics in organs and tissues. The authors have produced a very nice piece of work and written a paper which explains many details of the study in a clear and accessible manner.