Dynamics of Infection Spread and Hotspot Growth in Bi-Pathogen Networks

Abstract: Understanding the spatio-temporal evolution of epidemics with multiple pathogens requires not only new theoretical models but also careful analysis of their practical consequences. Building on the Multiplex Bi-Virus Reaction-Diffusion framework (MBRD) introduced in our companion paper, we investigate how the super-infection model (MBRD-SI) and the co-infection model (MBRD-CI) behave under different epidemiological and network conditions. Through numerical experiments, we study the effects of pathogen virulence, diffusion rates, and cross-diffusion on epidemic hotspot formation and long-term prevalence. Our results highlight the role of multiplex structure in amplifying or suppressing co-circulating infections, and provide quantitative insight into conditions that drive persistent epidemic patterns. Beyond epidemiology, these findings have broader implications for multiplex contagion processes such as information diffusion and malware propagation.