Awards

Joanne Macdonald from the University of the Sunshine Coast in Australia will develop a simple diagnostic test that can be used in the field to rapidly identify mosquitoes infected with pathogens such as the malaria parasite and dengue virus. Traditional methods require costly equipment and a laboratory setting. The test combines recombinase polymerase amplification (RPA) with a lateral flow strip and can detect DNA from multiple pathogens in parallel, which will reduce costs. They will first perform a proof-of-concept study using laboratory-infected mosquitoes to evaluate the test and develop smart-phone software to translate the results. They will then perform field trials in Cairns to evaluate if their test can detect single infected mosquitoes placed in field traps containing uninfected insects.

Heverton Dutra of Centro de Pesquisas René Rachou, FIOCRUZ in Brazil will develop an artificial diet based on protein and fat to sustain mosquitoes infected with the Wolbachia bacteria, which are needed in large numbers to prevent transmission of the dengue virus. These mosquitoes are currently being bred using vertebrate blood, which is difficult to obtain and store, and subject to stringent regulations. They will test variations of cholesterol and amino acids combined with the mixture of bovine serum albumin and phagostimulant that is known to support egg production in non-infected mosquitoes, on egg numbers laid by Wolbachia-infected females. The diet is relatively low cost and comprises widely available ingredients that could be used to support mass-rearing of Wolbachia-infected mosquitoes.

Henrique Silveira of the Instituto de Higiene e Medicina Tropical (IHMT) in Portugal and colleagues have identified a peptide in human blood that promotes female mosquito reproduction. They will test whether it can be added to artificial diets to improve mosquito breeding in the laboratory for studying vector-borne diseases like malaria. The human peptide activates a so-called G protein-coupled receptor in the mosquito, which somehow triggers reproduction. They will study the mechanism further, and use the most active form of the peptide to formulate an artificial meal and test its effect on different aspects of mosquito reproduction compared to a normal human blood meal.

Dawn Wesson and Sam Jameson of Tulane University in the U.S. will develop an artificial meal for mosquitoes based on algae as a protein source that can be freeze dried and stored in blister packs, and refine their reusable feeding system. Mosquitoes are currently laboratory reared using expensive and difficult to obtain mammalian blood to ensure adequate numbers of offspring for studying. They proposed that a spirulina (Arthrospira platensis) would be an ideal candidate for feeding mosquitoes due to it being a complex protein source, easy to mass produce, and dark in color, which is a feeding cue for mosquitoes. They will supplement it with insect juvenile hormone, which stimulates egg production, sugar and salt, and test its palatability and effect on egg production in a number of different mosquito species using iterations of their meal delivery system compared to human blood.

Koen Dechering of TropIQ in The Netherlands will produce an artificial meal for breeding blood-feeding mosquitoes more easily and effectively in the lab. They will develop a high-throughput screening approach using molecular barcodes carried by endosymbiont bacteria that each tag an individual meal consumed by a live mosquito. The barcodes can then be used to identify those meals that best promote egg laying and longevity from a large pool of test foods. They will rationally design the protein and lipid compositions of the test foods for their screen by using mass spectrometry on blood-fed mosquitoes. Optimized diets identified from the screen will be further validated and analyzed for stability also at tropical ambient temperatures.

Johanna Ohm of Pennsylvania State University in the U.S. will produce an insect-based diet for breeding adult malaria-transmitting Aedes and Anopheles mosquitoes in the laboratory. Laboratory mosquitoes are most effectively bred for research using mammalian blood meals, which has numerous limitations including higher costs and requiring human volunteers with stringent regulations. It is known that some mosquitoes can produce viable eggs after feeding on soft-bodied insect larvae such as lepidopteran larvae. They will screen a selection of larvae to identify the most palatable insect-based diets, and evaluate them for effect on mosquito survival, fecundity and offspring viability compared to mosquitoes reared on blood-based diets.

Bradley Willenberg at the University of Central Florida Research Foundation in the U.S. will design a simple trap that works without electricity to help survey local vector mosquito populations and uses a color change to signal the presence of human disease-causing pathogens. They will develop a formulation based on toxic sugared water to attract specific types of mosquitoes to the trap. The sugar water will be mixed with a stable short nucleic acid sequence known as an aptamer, which they have designed to bind to the chikungunya virus, conjugated to gold nanoparticles. When a mosquito drinks the solution, its abdomen will turn blue if it is carrying this virus, and red if it isn't, for an easy visual readout. They will test the performance of their device for attracting and killing the Aedes mosquito, and detecting the virus. Their approach could be used to detect other pathogens such as dengue virus and the malaria-causing Plasmodium parasite.

Paul Young of the University of Queensland in Australia will monitor mosquito populations using ultra bright nanoparticles coated with selected monoclonal antibodies to detect associated microbes such as Wolbachia, coupled with a low-cost readout device. The goal is a simple to use, portable platform that can be used in the field. They will develop the assay using a range of infected mosquitoes to identify the optimal antibody and nanoparticle format for rapid and specific detection, and evaluate sensitivity.

Laura Harrington of Cornell University in the U.S. will test whether acoustic signals in traps can attract specific disease-causing species of mosquitoes, particularly males, to aid control efforts. Traps usually use chemicals to mostly attract female mosquitoes searching for a blood meal. Mosquitoes are very sensitive to sounds, and males likely use them to identify mates. They will first test different frequencies and magnitudes of sounds representing wing beats from Aedes aegypti females, which transmit dengue fever, for their ability to elicit a physiological response in males. Selected sounds will then be tested and optimized using large field cages. They will also build field-ready solar- or battery-powered traps that can be remotely controlled by a cell phone app to alter the sound depending on time of day or species of mosquito being targeted.

Stephen Dobson of the University of Kentucky in the U.S. will adapt their lyophilized mosquito feed formulation to support growth of different disease-relevant mosquito species for control efforts. They will test their lyophilized formulation, which can be stored long term, on other Anopheles species and on Aedes aegypti mosquitoes infected with the intracellular bacterium Wolbachia, which are being used as a dengue fever control strategy. They will also test three different delivery methods to see if they can reduce associated costs by simplifying delivery.