The effects of landscape on West Nile virus sentinel chicken seroconversion varies by ecoregion in Florida

Abstract

Abstract West Nile virus (WNV) is the leading cause of mosquito-borne disease in the United States. Landscapes provide habitats and resources for WNV mosquito vectors and avian amplification hosts, and landscape composition and configuration can affect transmission opportunities. We examined landscape correlations with WNV in Florida, USA across the state and within five regions to understand potential transmission hazard. We expected higher percentages of residential or medium-developed landscapes and more fragmented landscapes would be positively correlated with WNV, and the importance of these factors would vary by region. WNV transmission rates were calculated using Florida 2018 Department of Health WNV sentinel chicken seroconversion data from 187 flocks maintained by mosquito control programs. Percent land cover and edge density metrics were calculated for multiple land cover classes and within multiple buffer distances from chicken coops using 2019 National Land Cover Data. We used binomial generalized linear mixed effects models to calculate the importance of landscape metrics to WNV seroconversion. While we found no statewide predictors of seroconversion, the importance of landscape composition and configuration varied across regions. A non-linear effect of percentage low-intensity urban within 5 km of coops suggested higher transmission in less populated suburban areas in the north-central region of Florida and more fragmented forested areas within 0.5 km of coops and intact woody wetland areas within 2 km of coops were positively correlated with seroconversion in the south-central region. This work provides new insight into the importance and complexity of regional landscape predictors of WNV transmission hazard across Florida.