Linking Wetland Structure, Configuration, and Inundation Patterns with Mosquito-Borne Disease Transmission

EPA Grant Number: FP917783
Title: Linking Wetland Structure, Configuration, and Inundation Patterns with Mosquito-Borne Disease Transmission
Investigators: Skaff, Nicholas Karam
Institution: Michigan State University
EPA Project Officer: Lee, Sonja
Project Period: September 1, 2015 through August 31, 2018
Project Amount: $132,000
RFA: STAR Graduate Fellowships (2015) RFA Text |  Recipients Lists
Research Category: Academic Fellowships

Objective:

The objective is to determine if several local-scale wetland characteristics — wetland size, connectivity, and inundation regime — influence the mosquito-driven transmission of West Nile virus (WNV) and Eastern equine encephalitis (EEE), and also to identify the mechanisms driving this relationship at both local and sub-continental (macroscale) spatial scales.

Approach:

The first phase of this project employs a spatially explicit GIS (geographic information systems)–based approach to evaluate vector infection rates and abundance surrounding Connecticut wetlands with the above–mentioned characteristics (“high–risk” wetlands). Higher mosquito abundance or infection rates at mosquito sampling sites near these wetlands would suggest that the wetlands facilitate transmission of WNV or EEE. Also, a moving-window statistical approach will be used to identify the distance from these wetlands at which vector infection rates and abundance decline. This will help to estimate the locations where human populations are most at risk of contact with an infected mosquito. Finally, a hierarchical, bootstrap-based analysis will test whether bird dispersal (birds are the primary host for WNV) and/or mosquito dispersal from “high–risk” wetlands primarily drives macroscale patterns in human WNV infection over a 17–state study area (midwestern and northeastern USA) encompassing nearly 3 millions wetlands.

Expected Results:

Mosquitoes sampled at locations close to irregularly flooded wetlands and small wetlands are expected to have higher WNV and EEE infection rates. This is because these wetland characteristics may facilitate contact between mosquitoes and vulnerable bird hosts, and thus promote an increase in viral prevalence near the wetland. Also, mosquitoes are expected to be in higher abundance near wetlands lacking connectivity with other waterbodies like streams, because previous research indicates that low–connectivity wetlands have low mosquito predator (e.g. fish) abundance. Lastly, both mosquito and bird dispersal are expected to furnish a compelling mechanistic link between local–level wetland characteristics and human infection patterns over much larger spatial scales.

Supplemental Keywords:

mosquito-borne disease, West Nile virus, macroscale, wetlands, drought, connectivity

Progress and Final Reports:

  • 2016
  • 2017
  • Final