Location: Arthropod-borne Animal Diseases Research
Project Number: 3020-32000-007-00-D
Project Type: In-House Appropriated
Start Date: Oct 23, 2014
End Date: Sep 30, 2019
Objective 1: Perform risk assessment of bacterial pathogen transmission by house flies. Sub-objective 1.A: Develop more effective larval control techniques by understanding the role of microbes in larval development and fitness. Sub-objective 1.B: Evaluate the role of fly-bacteria and bacteria-bacteria interactions in house fly pathogen transmission. Objective 2: Determine biological characteristics of mosquito vectors influencing animal health in a changing climate. Sub-objective 2.A: Model mosquito ecological niches and impact of climate change. Sub-objective 2.B: Characterize the biology of discrete mosquito populations. Objective 3: Develop methods to reduce biting midge transmission of animal pathogens. Sub-objective 3.A: Identify and characterize the salivary protein components of Culicoides sonorensis. Sub-objective 3.B: Identify potential Culicoides vectors of epizootic hemorrhagic disease and bluetongue. Sub-objective 3.C: Determine breeding site characteristics of Culicoides spp.. Sub-objective 3.D: Evaluate efficacy of candidate pesticides against C. sonorensis.
An extremely small percentage of insect species transmit disease-causing pathogens to animals and humans. Specific biological and behavioral characteristics allow these vector insect species to be efficient means of pathogen propagation and transmission; however these same characteristics may be targeted by control measures to limit pathogen spread or disease vector abundance. The common purpose of these projects is to understand key components of the host-pathogen-vector cycle to reduce or prevent pathogen transmission by the most common disease vectors: house flies, mosquitoes, and biting midges (Fig. 1). House flies associate with bacteria-rich environments due to the nutritional requirements of their larvae. This research defines the role of bacteria in fly development, bacterial persistence during microbe and insect interactions, and pathogen dissemination. Natural selection for increased Culex tarsalis mosquito fitness for various habitats and animal hosts has left genetic markers (single nucleotide polymorphisms) throughout the genome. These markers can be associated with traits and used to predict regional entomological risk in a changing climate throughout the mosquito’s large geographic range. The identification of biting midges or Culicoides saliva components that facilitate pathogen transmission will lead to improved transmission and pathogenesis models. This information will enhance development of vaccines and other countermeasures to reduce disease transmission. Lastly, not all Culicoides are competent vectors and this study will determine vector species and their habitats to help estimate risk in specific geographic regions. This plan aims to limit pathogen transmission by targeting the connections between hosts, vectors, and their environments via the insects’ unique characteristics using novel disease control methods.