DISEASE EXTINCTION AND COMMUNITY SIZE - MODELING THE PERSISTENCE OF MEASLES

A basic issue in ecology is the relation between extinction and popula tion size. One of the dearest manifestations of a population threshold for extinction is the critical community size below which infections like measles do not persist. The current generation of stochastic mode ls overestimates the observed critical community size for measles, gen erating much less persistence of infection than is observed. The inclu sion of a more biologically realistic model for the duration of infect ion produced a much closer fit to the actual critical community size a nd explains previously undescribed high-frequency oscillations in meas les incidence.