The present study deals with the dynamical response of an eco-epidemiological
model consisting of prey and predator species having infection in prey
population. The inclusion of prey refugia is taken into account to avoid
predator attack. The entire prey population is divided into two parts:
healthy prey which are capable of reproducing following the logistic law and
infected prey which is removed by predation or death before having the
possibility of reproducing. This dynamical system assumes that predators
form a dense colony or school in a single (possibly moving) location to
encounter a prey and due to that an encounter between the prey and a single
predator is immediately converted into an encounter between the prey and all
the predators. This special type of interaction is approximated by a
response function which is ratio dependent at high predator density. The
dynamical responses in terms of boundedness, the local stability and
bifurcation are studied in detail. Numerical simulations are performed at
the end in order to exhibit the dynamical behavior of the present system for
the occurrence of limit cycle and bifurcation based on the analytical
results and choice of parameters involved in it.