Background
Arthropod-borne viruses (arbovirus) transmitted by mosquitoes cause thousands of disease cases each year in Australia and remain a leading cause of morbidity and mortality internationally. Currently, there are no widely effective vaccines for most of the arboviruses, making mosquito population control the primary strategy for managing disease transmission. In addition to carrying human-pathogenic viruses, mosquitoes also harbour a variety of microbes that can be beneficial; including the intracellular bacteria Wolbachia and insect-specific viruses (ISVs), which are passed vertically from female mosquitoes to their offspring via the eggs. Mosquito infection with these microbes have been shown to inhibit infection of the mosquitoes with pathogenic arboviruses. Wolbachia are now applied worldwide as biological control agents for the control of dengue. Native mosquitoes harbour a range of uncharacterised Wolbachia strains, with untapped potential for disease control. While much work has been performed on ISVs in cell culture, mosquito infections have not been evaluated for most ISVs. In partnership with the University of Queensland, we are characterising native ISV infections in globally important mosquito vectors.
Aim
Projects on these microbes aim to establish new infection of vector mosquitoes with microbial agents and evaluate their potential for disease control.
Approach
New infections of mosquito vectors with beneficial micro-organisms will be established by methods including mosquito microinjection. Vertical transmission will be evaluated and strains that are passed on at high frequency will be prioritised for further analysis. Mosquitoes with persistent infections will be evaluated for susceptibility to pathogenic arboviruses. Procedures performed would include mosquito microinjection, cell and mosquito culturing, histology and microscopy and applied virology testing procedures.
Project Potential
Results from this project will inform regulatory applications for the development of these beneficial microbes as biological control agents against arboviruses.