Flavivirus Susceptibility in Aedes aegypti

Abstract

Aedes aegypti is the primary vector of yellow fever (YF) and dengue fever (DF) flaviviruses worldwide. In this review we focus on past and present research on genetic components and environmental factors in Aedes aegypti that appear to control flavivirus transmission. We review genetic relationships among Ae. aegypti populations throughout the world and discuss how variation in vector competence is correlated with overall genetic differences among populations. We describe current research into how genetic and environmental factors jointly affect distribution of vector competence in natural populations. Based on this information, we propose a population genetic model for vector competence and discuss our recent progress in testing this model. We end with a discussion of approaches being taken to identify the genes that may control flavivirus susceptibility in Ae. aegypti.

Impact of Climate and Mosquito Vector Abundance on Sylvatic Arbovirus Circulation Dynamics in Senegal

“…aegypti are all widely present in Senegal 3 and differ dramatically in their experimentally determined vector competencies for DENV and YFV. 22 The DENV dissemination rates for Ae. furcifer captured in Senegal can be as high as 75%, 13 whereas those for YFV are estimated at 20%.…”

Mosquito-Borne Arboviral Surveillance and the Prediction of Disease Outbreaks

“…To function as a competent mosquito vector, ingested virus must be able to escape the mosquito midgut, infect other organs, replicate, and eventually infect the mosquito's salivary glands from where it is then transmitted with each subsequent probe or blood meal. Intrinsic factors in all mosquitoes regulate viral escape from infected organs, the penetration of virus into new organs, and viral replication within those organs (Black et al 2002). Extrinsic factors including the amount of virus ingested by the mosquito with its first infective blood meal and ambient temperature, which determines how quickly the virus replicates in the mosquito and infects the salivary glands (a process known as the extrinsic incubation period (EIP)), also influence mosquito vector competence (Anderson et al 2010, Richards et al 2009.…”

Wolbachia enhances insect‐specific flavivirus infection in Aedes aegypti mosquitoes

“…These viruses belong to diverse families including the Flaviviridae (genus: Flavivirus ) that are positive single‐stranded RNA viruses (Fauquet, Mayo, Maniloff, Desselberger, & Ball, 2005; Karabatsos, 1978). Flaviviruses include Japanese encephalitis virus and Murray Valley encephalitis virus transmitted by Culex species (Erlanger, Weiss, Keiser, Utzinger, & Wiedenmayer, 2009; Kay, Fanning, & Carley, 1984), West Nile virus (WNV) transmitted by a diverse group of mosquitoes including Aedes and Culex species (Mackenzie et al., 2004) and yellow fever virus (YFV), Zika virus (ZIKV), and dengue virus (DENV) that are all transmitted by Aedes aegypti and Aedes albopictus (Black et al., 2002; Hall‐Mendelin et al., 2016; Hayes, 2009). Dengue fever caused by DENV is a severely debilitating disease with 40% of the world's population at risk of infection and an estimated 300 new infections reported yearly (Bhatt et al., 2013).…”