Submitted to: Viruses
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/6/2021
Publication Date: 9/12/2021
Citation: Humphreys Jr, J.M., Pelzel-McCluskey, A.M., Cohnstaedt, L.W., McGregor, B.L., Haney, K.A., Young, K.I., Hudson, A.R., Peck, D.E., Rodriguez, L.L., Peters, D.C. 2021. Integrating spatiotemporal epidemiology, eco-phylogenetics, and distributional ecology to assess West Nile disease risk in horses Viruses. https://doi.org/10.3390/V13091811.
DOI: https://doi.org/10.3390/V13091811

Interpretive Summary: This research was conducted as part of the USDA Predictive Disease Ecology Grand Challenge Synergy which aims to assess disease risk to agricultural systems. The research evaluated ecological risk factors associated with West Nile Disease , a disease that effects humans, livestock, and wildlife. The findings highlight that mosquito and bird occurrence and community species composition are important indicators of disease risk in horses.

Technical Abstract: Mosquito-borne West Nile virus (WNV) is the causative agent of West Nile disease in humans, horses, and some bird species. Since the initial introduction of WNV to the United States (US), approximately 30,000 horses have been impacted by West Nile neurologic disease and hundreds of additional horses are infected each year. Research describing the drivers of West Nile disease in horses is greatly needed to better anticipate the spatial and temporal extent of disease risk, improve disease surveillance, and alleviate future economic impacts to the equine industry and private horse owners. To help meet this need, we integrated techniques from spatiotemporal epidemiology, eco-phylogenetics, and distributional ecology to assess West Nile disease risk in horses throughout the contiguous US. Our integrated approach considered horse abundance and virus exposure, vector and host distributions, and a variety of extrinsic climatic, socio-economic, and environmental risk factors. Birds are WNV reservoir hosts, therefore, we quantified avian host community dynamics across the continental US to show intra-annual variability in host phylogenetic structure and demonstrate host phylodiversity as a mechanism for virus amplification in time and virus dilution in space. We identified drought as a potential amplifier of virus transmission and demonstrated the importance of accounting for spatial non-stationarity when quantifying interaction between disease risk and meteorological influences like temperature and precipitation. Our results delineated the timing and location of several areas at high-risk of West Nile disease and can be used to prioritize and optimize virus surveillance and monitoring.