Criticality of Parasitic Disease Transmission in a DiffusivePopulation

Through using the methods offinite-size effect and short time dynamic scaling, we study the criticalbehavior of parasitic disease spreading process in a diffusive populationmediated by a static vector environment. Through comprehensive analysis ofparasitic disease spreading we find that this model presents a dynamicalphase transition from disease-free state to endemic state with a finitepopulation density. We determine the critical population density, above whichthe system reaches an epidemic spreading stationary state. We also perform ascaling analysis to determine the order parameter and critical relaxationexponents. The results show that the model does not belong to the usualdirected percolation universality class and is compatible with the class ofdirected percolation with diffusive and conservedfields.