Paper

Under-the-radar dengue virus infections in natural populations of Aedes aegypti mosquitoes

Baumgartner, Caleb, Buckner, Eva A, Kang, Seokyoung, Prosperi, Mattia, Salemi, Marco, Mavian, Carla N, Stephenson, Caroline J, Williams, Kate, Boyles, Sean M, Stinton, Israel, Ukhanova, Maria, Rivers, Adam R, Geesey, Mary, Finol, Esteban, Mai, Volker, Dinglasan, Rhoel R, Mathias, Derrick K, Lednicky, John A, Hamerlinck, Gabriela

2020

Overview

The incidence of locally acquired dengue infections increased during the last decade in the United States, compelling a sustained research effort on the dengue mosquito vector, Aedes aegypti, and its microbiome, which has been shown to influence virus transmission success. We examined the 'metavirome' of four populations of Ae. aegypti mosquitoes collected in 2016-2017 from Manatee County, Florida. Unexpectedly, we discovered that dengue virus serotype 4 (DENV4) was circulating in these mosquito populations, representing the first documented case of such a phenomenon in the absence of a local DENV4 human case in this county over a two-year period. We confirmed that all of the mosquito populations carried the same DENV4 strain, assembled its full genome, validated infection orthogonally by reverse transcriptase PCR, traced the virus origin, estimated the time period of its introduction to the Caribbean region, as well as explored the viral genetic signatures and mosquito-specific virome associations that potentially mediated DENV4 persistence in mosquitoes. We discuss the significance of prolonged maintenance of these DENV4 infections in Ae. aegypti that occurred in the absence of a DENV4 human index case in Manatee County with respect to the inability of current surveillance paradigms to detect mosquito vector infections prior to a potential local outbreak.

• Publisher: Cold Spring Harbor Laboratory Press,Cold Spring Harbor Laboratory
• Subject: Aedes aegypti / Culicidae / Dengue fever / Ecology / Genomes / Infections / Microbiomes / Mosquitoes / RNA-directed DNA polymerase