Covariance plots for model II from Seasonality and the persistence of vector-borne pathogens

The graphs of the biting rate $a$, the vector population $I_V^*$ and $ the host population IH* are plotted. The covariances are computed and their sign shown to depend on the sign of μV − (μH + γH), that is on the comparison of the 'lifetimes' of vectors and hosts. All the parts of Figure 6 of the main text are produced.