Ecoepidemics with a nonlinear disease incidence

We present two new models for interacting populations subject to a transmissible disease. The novelty lies in the assumption that herd behavior influences the disease incidence, rather than the demographic description of the interactions, as in previous related similar models. As it is already known from other ecoepidemiological situations, the epidemics may affect the system demographic outcomes

Predator's alternative food sources do not support ecoepidemics with two-strains-diseased prey

An ecoepidemic model is presented, in which two diseases affect the prey. Predators are allowed to have other food sources. Equilibria are analyzed for feasibility and stability. The most striking result is that in these conditions the two strains cannot both survive in the system, contrary to what is possible to obtain, under suitable assumptions, in standard epidemic models

An ecoepidemic model with healthy prey herding and infected prey drifting away

We introduce here a predator–prey model where the prey are affected by a disease. The prey are assumed to gather in herds, while the predators are loose and act on an individualistic basis. Therefore their hunting affects mainly the prey individuals occupying the outermost positions in the herd, which is modeled via a square root functional response. The conditions of boundedness and uniform persistence are established. Stability and bifurcation analysis of all feasible equilibrium are carried out. Conditions on the model parameters for the possible existence of limit cycles are derived, global stability analysis is also shown in proper choice of suitable Lyapunov function. Numerical simulation of the various bifurcations validate the theoretical results. It is found that the system ultimate behavior depends mainly on two crucial parameters, the force of infection and predator average handling time. A discussion of the biological significance of the investigation concludes the paper