Monitoring and control of mosquito vectors for West Nile Virus (WNV) via exploration of their host location cues for mitigation of climatic driven zoo

In 2023, 707 cases of West Nile Virus (WNV) disease were reported in EU/EEA countries leading to 67 deaths. The increase in WNV incidence in Europe has been attributed in part to a rise in ambient temperature associated with climate change. Increased ambient temperatures have been shown to increase mosquito survival, growth rates and reduce intervals between blood meals. Moreover, the increased ambient temperatures can accelerate viral replication within vectors.
WNV infection is a zoonotic disease found mainly in bird populations and spread by mosquitoes as the virus vector. Mosquito vector species, that spread the virus, primarily feed on birds but will currently only occasionally feed on mammals including human individuals where suitable birds are less available. Human infection can develop into a serious, sometimes fatal, illness. Currently there are no prophylaxis or treatments for disease caused by WNV.
This project aims to address this current growing threat, and create a framework to tackle other vector-borne zoonotic diseases, through monitoring and control of the vector species by exploiting olfactory cues. The successful student will work on identifying chemicals important in host location for use in products to control vectors. To achieve this aim, the student will be supported by experts in chemical ecology, insect olfaction, and vector borne disease.
The vector species' under investigation will be Culex pipiens and Aedes vexans. Both Species are endemic within the UK and are competent vectors for WNV.
C.pipiens primarily feeds on avian populations but will additionally feed on mammals. Recent WNV outbreaks in Germany have been attributed to C.pipiens acting as a bridging vector.
Ae.vexans is primarily a mammalian feeding mosquito, however the close proximity in urban areas of mammals and birds, and the increasing population of this species has caused greater concern of a possible zoonosis, and the establishment of WNV in populations of Ae.vexans. which would further transmission in mammals. To address these growing concerns, a colony of Ae.vexans is being set up at the London School of Hygiene and Tropical Medicine, and then student will have access to this population for testing.
The student will work with the School of Chemistry - Cardiff University, School of Biosciences - Cardiff University, The London School of Hygiene & Tropical Medicine | LSHTM and the commercial insect trap company Biogents AG Biogents: mosquito specialists - Biogents AG to explore the chemical ecology of mosquito vectors of WNV, identifying important chemical components of host location, and uncovering the biological route for perception of these compounds, to allow for effective vector control. Successful identification of compounds important to olfactory host-location of the vector species' will allow for the formulation and testing of attractant chemical lures in partnership with Biogents AG.
Aims:
Collection of host-derived headspace volatiles from human volunteers at the London School of Hygiene and Tropical Medicine.
Completion of electrophysiological assays of vector olfactory systems to create a functional map of olfactory neurons present in vector mosquitos.
Completion of Gas Chromatography coupled Electrophysiology of identified olfactory neurons with host derived volatiles to identify olfactory significant aspects of host volatiles.
Chemical identification of the identified olfactory significant aspects of host volatiles, via GC-MS analysis followed by chemical synthesis in order to confirm identity via chemical analysis, and to confirm olfactory significance via electrophysiological recordings.