  We study dynamics of a variant of the SIR the model, where we assume that
individuals respond differently to dynamics of the epidemic. Their
heterogeneous response is modeled by the Preisach hysteresis operator. The
degree of heterogeneity of the response is measured by the variance $\sigma^2$
of the corresponding distribution (the Preisach density function). The proposed
model has a continuum of endemic equilibrium states characterized by different
proportions of susceptible, infected and recovered populations. We consider how
the limit point of the epidemic trajectory and the infection peak along this
trajectory depend on $\sigma$. The heterogeneous model is compared to the the
switched model with an ideally uniform response corresponding to $\sigma=0$.
