Avian Host Preference by Vectors of Eastern Equine Encephalomyelitis Virus

Abstract

Abstract. An important variable in the amplification and escape from the enzootic cycle of the arboviral encephalitides is the degree of contact between avian hosts and mosquito vectors. To analyze this interaction in detail, blood-fed mosquitoes that were confirmed vectors of eastern equine encephalomyelitis (EEE) virus were collected in 2002 from an enzootic site in central Alabama during the time this virus was actively transmitted. Avian-derived blood meals were identified to the species level of the host, and the proportion derived from each species was compared with the overall composition of the avifauna at the study site. The EEE vector mosquito species fed significantly more on some bird species and less on other species than expected given the overall abundance, biomass, or surface area of the local avifauna. When viewed collectively, these data suggest that these mosquitoes are selectively targeting particular avian species.

Host heterogeneity dominates West Nile virus transmission

“…Transmission of many other multi-host pathogens is also likely to be influenced by heterogeneity due to differences in host-vector contact rates, differences in infectiousness among hosts (St Louis encephalitis virus; Reisen et al 2003) or both (eastern equine encephalitis virus (Komar et al 1999;Hassan et al 2003); Lyme disease: variation in relative tick burdens ). Host heterogeneity is also likely to impact the transmission of directly transmitted multi-host pathogens such as avian influenza (Alexander 2000;Guan et al 2004).…”

“…We tested whether P i for each species at each site was significantly different from 1 by performing 10 000 multinomial simulations comparing the observed distribution of blood meals between species with those expected under the null hypothesis that mosquitoes fed on birds in proportion to their abundance (Hassan et al 2003). Culex mosquitoes obtain blood meals every 6-21 days and can live for 10-65 days in captivity, depending on temperature (Oda et al 1999;Spielman & D'Antonio 2001).…”

Ecology of West Nile Virus Transmission and Its Impact on Birds in the Western Hemisphere

“…tarsalis in California (Tempelis et al 1965), and Cx. erraticus in Alabama (Hassan et al 2003), and this is likely to intensify WNV epidemics in humans in these regions (Kilpatrick et al 2006d). Third, Mourning Doves (Zenaida macroura) appear to be fed on frequently in some areas (Kilpatrick et al 2006c;Molaei et al 2006Molaei et al , 2007 but, given their relatively low viremias , Reisen et al 2005a, they are more likely to dampen than amplify WNV epidemics.…”

Host compatibility rather than vector–host-encounter rate determines the host range of avian Plasmodium parasites

“…Thus, bloodfeeding patterns effectively set the encounter rate between vector-borne parasites and hosts. Mosquitoes, which are important vectors for a diversity of pathogens, are known to feed heterogeneously across hosts by using some species disproportionately, relative to their abundance [13][14][15]. This heterogeneity in mosquito-feeding patterns can strongly influence disease transmission dynamics [3,4,13,16].…”