There are many factors that govern the potential for arbovirus emergence and expansion, including host factors and regional environmental conditions, yet the foremost drivers of emergence and spread are the interactions between virus and vector. West Nile virus (WNV; Flaviviridae; Flavivirus) remains the most geographically widespread arbovirus globally and the most widespread and prevalent arbovirus in the U.S, including in New York State (NYS). A resurgence in WNV activity was seen in NYS in 2010 and nationwide in 2012, and our retrospective genetic studies now demonstrate that this was concurrent with genetic change. Prevalence of WNV in NYS mosquitoes last year was 2nd only to 2012, and WNV cases in upstate NY reached unprecedent levels. Although environmental shifts likely play a role in epidemiological patterns, our recent analyses have led us to hypothesize that genetic variation of WNV correlates to shifts in population- specific vectorial capacity, and that this contributes to WNV transmission and disease intensity. Our proposed studies aim to understand the phenotypic impact of WNV genotype and its role in prevalence and disease. We will combine widespread surveillance and deep-sequencing with comprehensive laboratory studies utilizing historic and contemporary isolates, reverse genetics and experimental studies in relevant genetically-distinct mosquito populations. These data together will provide a direct assessment of the role of emergent genotypes in driving WNV transmission and the importance of population-specific selection and competence. In addition, the comprehensive catalog of virus strains will allow us to launch detailed downstream mechanistic studies.

Public Health Relevance

Studies are proposed to track genetic diversity and genotype displacement of West Nile virus in New York State, and to identify the impact of circulating mutations on population-specific transmission of WNV. These objectives will be accomplished by combining deep sequencing and reverse genetics studies with experimental infections in relevant Culex populations. These data will have direct implications for public health and be broadly informative to advancing our understanding of arbovirus evolution and vector-virus interactions.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21AI146856-02
Application #
10086956
Study Section
Vector Biology Study Section (VB)
Program Officer
Morabito, Kaitlyn Melissa
Project Start
2020-01-21
Project End
2021-12-31
Budget Start
2021-01-01
Budget End
2021-12-31
Support Year
2
Fiscal Year
2021
Total Cost
Indirect Cost
Name
Wadsworth Center
Department
Type
DUNS #
153695478
City
Menands
State
NY
Country
United States
Zip Code
12204