title: Risk of exposure to eastern equine encephalomyelitis virus increases with the density of northern cardinals.
abstract: For a variety of infectious diseases, the richness of the community of potential host species has emerged as an important factor in pathogen transmission, whereby a higher richness of host species is associated with a lowered disease risk. The proposed mechanism driving this pattern is an increased likelihood in species-rich communities that infectious individuals will encounter dead-end hosts. Mosquito-borne pathogen systems potentially are exceptions to such "dilution effects" because mosquitoes vary their rates of use of vertebrate host species as bloodmeal sources relative to host availabilities. Such preferences may violate basic assumptions underlying the hypothesis of a dilution effect in pathogen systems. Here, we describe development of a model to predict exposure risk of sentinel chickens to eastern equine encephalitis virus (EEEV) in Walton County, Florida between 2009 and 2010 using avian species richness as well as densities of individual host species potentially important to EEEV transmission as candidate predictor variables. We found the highest support for the model that included the density of northern cardinals, a highly preferred host of mosquito vectors of EEEV, as a predictor variable. The highest-ranking model also included Culiseta melanura abundance as a predictor variable. These results suggest that mosquito preferences for vertebrate hosts influence pathogen transmission.
authors.affiliation: Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon, United States of America. estepl@science.oregonstate.edu
authors.forename: Laura K
authors.initials: LK
authors.lastname: Estep
authors.forename: Christopher J W
authors.initials: CJ
authors.lastname: McClure
authors.forename: Patrick
authors.initials: P
authors.lastname: Vander Kelen
authors.forename: Nathan D
authors.initials: ND
authors.lastname: Burkett-Cadena
authors.forename: Stephen
authors.initials: S
authors.lastname: Sickerman
authors.forename: José
authors.initials: J
authors.lastname: Hernandez
authors.forename: Joseph
authors.initials: J
authors.lastname: Jinright
authors.forename: Brenda
authors.initials: B
authors.lastname: Hunt
authors.forename: John
authors.initials: J
authors.lastname: Lusk
authors.forename: Victor
authors.initials: V
authors.lastname: Hoover
authors.forename: Keith
authors.initials: K
authors.lastname: Armstrong
authors.forename: Lillian M
authors.initials: LM
authors.lastname: Stark
authors.forename: Geoffrey E
authors.initials: GE
authors.lastname: Hill
authors.forename: Thomas R
authors.initials: TR
authors.lastname: Unnasch
mesh_terms: D000818:Animals; D002645:Chickens / Q000821:virology; D009033:Culicidae / Q000502:physiology; D004663:Encephalitis Virus, Eastern Equine / Q000502:physiology*; D004781:Environmental Exposure / Q000706:statistics & numerical data*; D007303:Insect Vectors / Q000502:physiology; D015233:Models, Statistical; D046109:Passeriformes / Q000254:growth & development*; D011156:Population Density; D012306:Risk; D062206:Spatial Analysis