Seasonality, parasite diversity, and local extinctions in Plasmodium falciparum malaria

We incorporate stochastic, density-dependent seasonal recruitment in adult Anopheles mosquito populations in a discrete-event model of Plasmodium falc iparum malaria transmission and find the probabilities of parasite extincti on higher than with perennial transmission. Seasonal fluctuations in vector populations act to synchronize the dynamics of infection and immunity in h ost populations, leading to fluctuations in parasite prevalence greater tha n expected solely on the basis, of high- and low-season vector densities. T his synchronization also biases frequencies of infection with multiple para site phenotypes or genotypes.