Periodic solutions and global attractivity of a discrete delay host macroparasite model.

In this paper, we develop a general approach to the existence of periodic solutions for the difference equation[image omitted] with variable delays and apply it to find necessary and sufficient conditions for the existence of a positive periodic solution [image omitted] for the host macroparasite model. We present some sufficient conditions for the global attractivity of [image omitted] . For the constant coefficients nondelay case, we obtain necessary and sufficient attractivity conditions using recent results of Liz. [ABSTRACT FROM AUTHOR]