Linking Bird and Mosquito Data to Assess Spatiotemporal West Nile Virus Risk in Humans


West Nile virus (WNV; family Flaviviridae) causes a disease in humans that may develop into a deadly neuroinvasive disease. In North America, several peridomestic bird species can develop sufficient viremia to infect blood-feeding mosquito vectors without succumbing to the virus. Mosquito species from the genus Culex, Aedes and Ochlerotatus display variable host preferences, ranging between birds and mammals, including humans, and may bridge transmission among avian hosts and contribute to spill-over transmission to humans. In this study, we aimed to test the effect of density of three mosquito species and two avian species on WNV mosquito infection rates and investigated the link between spatiotemporal clusters of high mosquito infection rates and clusters of human WNV cases. We based our study around the city of Ottawa, Canada, between the year 2007 and 2014. We found a large effect size of density of two mosquito species on mosquito infection rates. We also found spatiotemporal overlap between a cluster of high mosquito infection rates and a cluster of human WNV cases. Our study is innovative because it suggests a role of avian and mosquito densities on mosquito infection rates and, in turn, on hotspots of human WNV cases.

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We thank Canadian Institutes of Health Research for funding of the project. We thank employees of GDG Environment for their mosquito abundance and WNV test data, volunteers of Ontario Bird Count for access to their spatially interpolated bird density data, employees of Ottawa Public Health for their human WNV case data, and employees of Environment and Natural Resources Canada for meteorological data. We thank Monir Taha for their useful comments on an earlier version of the manuscript. We thank all members from the INSIGHT lab for their suggestions and comments on the analyses and the initial draft of the manuscript.

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Correspondence to Benoit Talbot.

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Talbot, B., Caron-Lévesque, M., Ardis, M. et al. Linking Bird and Mosquito Data to Assess Spatiotemporal West Nile Virus Risk in Humans. EcoHealth 16, 70–81 (2019).

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  • Aedes vexans
  • American robin
  • Culex pipiens/restuans
  • Disease ecology
  • Epidemiology
  • House finch
  • Ochlerotatus japonicus