title: Predicting the mosquito species and vertebrate species involved in the theoretical transmission of Rift Valley fever virus in the United States.
abstract: Rift Valley fever virus (RVFV) is a mosquito-borne virus in the family Bunyaviridiae that has spread throughout continental Africa to Madagascar and the Arabian Peninsula. The establishment of RVFV in North America would have serious consequences for human and animal health in addition to a significant economic impact on the livestock industry. Published and unpublished data on RVFV vector competence, vertebrate host competence, and mosquito feeding patterns from the United States were combined to quantitatively implicate mosquito vectors and vertebrate hosts that may be important to RVFV transmission in the United States. A viremia-vector competence relationship based on published mosquito transmission studies was used to calculate a vertebrate host competence index which was then combined with mosquito blood feeding patterns to approximate the vector and vertebrate amplification fraction, defined as the relative contribution of the mosquito or vertebrate host to pathogen transmission. Results implicate several Aedes spp. mosquitoes and vertebrates in the order Artiodactyla as important hosts for RVFV transmission in the U.S. Moreover, this study identifies critical gaps in knowledge which would be necessary to complete a comprehensive analysis identifying the different contributions of mosquitoes and vertebrates to potential RVFV transmission in the U.S. Future research should focus on (1) the dose-dependent relationship between viremic exposure and the subsequent infectiousness of key mosquito species, (2) evaluation of vertebrate host competence for RVFV among North American mammal species, with particular emphasis on the order Artiodactyla, and (3) identification of areas with a high risk for RVFV introduction so data on local vector and host populations can help generate geographically appropriate amplification fraction estimates.
authors.affiliation: Department of Entomology, Texas A&M University, College Station, Texas, United States of America.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Golnar
authors.affiliation: Virology Division, United States Army Medical Research Institute of Infectious Diseases, Fort Detrick, Frederick, Maryland, United States of America.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Turell
authors.affiliation: Center of Immunobiology and Vaccine Development, Children's Hospital Oakland Research Institute, Oakland, California, United States of America.
authors.forename: A Desiree
authors.initials: AD
authors.lastname: LaBeaud
authors.affiliation: Division of Vector-Borne Diseases, Arbovirus Diseases Branch, Centers for Disease Control and Prevention, Fort Collins, Colorado, United States of America.
authors.forename: Rebekah C
authors.initials: RC
authors.lastname: Kading
authors.affiliation: Department of Entomology, Texas A&M University, College Station, Texas, United States of America.
authors.forename: Gabriel L
authors.initials: GL
authors.lastname: Hamer
mesh_terms: D000818:Animals; D019295:Computational Biology; D009033:Culicidae / Q000821:virology*; D006801:Humans; D007303:Insect Vectors / Q000821:virology*; D015233:Models, Statistical; D012295:Rift Valley Fever / Q000453:epidemiology / Q000635:transmission* / Q000821:virology*; D012296:Rift Valley fever virus / Q000302:isolation & purification*; D014481:United States / Q000453:epidemiology; D014714:Vertebrates / Q000821:virology*