Location: Arthropod-borne Animal Diseases Research
Project Number: 3020-32000-020-000-D
Project Type: In-House Appropriated
Start Date: Dec 16, 2021
End Date: Dec 15, 2026
Objective 1. Determine biotic and abiotic factors mediating orbivirus transmission in the United States. • Identify molecular targets for orbivirus cell surface attachment to inform host range susceptibility. • Determine physiological effects of orbivirus infection of C. sonorensis biting midges on vectorial capacity. • Assess effects of increasing global temperatures on orbivirus transmission by C. sonorensis biting midges to inform predictive biology and disease ecology. • Identify and characterize habitats of immature Culicoides to determine species distributions and densities. Objective 2. Develop intervention strategies to minimize the impact of disease outbreaks caused by Orbiviruses. • Identify vector transmission control strategies based on our understanding of vector-Orbivirus interactions.
While there are many critical aspects of orbivirus transmission that are poorly understood for assessing disease risk and developing mitigation strategies, it is clear that the multi-host transmission dynamics and maintenance of orbiviruses in nature requires susceptible, viremic animals, and competent Culicoides biting midge vectors. Identifying biotic and abiotic factors affecting these orbivirus-vector-host interactions from a molecular to organismal scale, and from basic science to applied, is key to understanding orbiviral emergence, spread, adaptation to new environments, and to developing effective control strategies. In Objective 1, we will investigate biotic factors including virus-host molecular interactions, to better understand host range susceptibility (Obj. 1A), and virus-vector interactions, to better understand effects of viral infection on midge physiology (Obj. 1B) and inform how infected vector population densities are affected during outbreaks. We will investigate abiotic factors including the effects of environmental temperature on vector competence, allowing us to determine how rising global temperatures may alter vector-borne transmission dynamics (Obj. 1C), and how ecological conditions alter suitability of midge breeding habitats, affecting population distributions, densities, and transmission potential to nearby animals (Obj. 1D). In Objective 2, we will investigate virus-vector interactions to inform novel methods for disease surveillance, midge management, and identify targets to block virus transmission. We will investigate the effects of virus infection on midge sensory responses and exploit virus-induced physiological changes to improve midge management strategies using light traps (Obj. 2A), specifically targeted to orbivirus-infected Culicoides vectors. Outcomes of this research will 1) address key knowledge gaps in virus-vector-host-environment interactions which underlie orbivirus transmission dynamics and our ability to predict risk to livestock and wildlife, and 2) lead to improved, novel intervention strategies to minimize the impact of these devastating hemorrhagic diseases in the US.