Threshold parameters for epidemics in different community settings.

Threshold parameters of epidemic models play a central role in the assessment of proposed control strategies for infectious diseases. They have been determined for numerous standard epidemic models. This paper points out, with several examples, that threshold parameters depend on the social setting of the community and the variations in the behavior of the members of the community. Specifically, communities are considered in which individuals have fixed patterns of behavior or random patterns of behavior as well as communities of households with fixed or random patterns of behavior. A threshold parameter is computed for each of the different settings. Some comparisons are made to provide insights into the effects that social settings and behavior changes have on the threshold parameters.