Amplification due to spatial clustering in an individual-based model of mosquito-avian arbovirus transmission.

Theory and observations indicate that spatial clustering of birds and mosquitoes may be necessary for epizootic amplification of arboviruses with avian zoonoses. In this paper, I present an individual-based model of zoonotic arbovirus transmission among birds and mosquitoes. The results of initial ensemble model simulations indicate that the co-location of a vector mosquito oviposition site with an infected bird roost increases the local vector-to-host density and increases the likelihood of arbovirus amplification within the infected roost. Such amplification also increases the likelihood of secondary amplification at other roost sites, produces higher vector and host infection rates, increases the time to virus extinction within the model population, and increases the total number of birds infected. Additional oviposition locations within the model domain also increase the likelihood of secondary amplification. These findings support the idea that spatial clustering of mosquitoes and birds may facilitate arbovirus amplification. This model provides a basis for future exploration of specific zoonotic transmission cycles, including West Nile virus, and could be used to test the efficacy of various control strategies.