The USAID “Combating Zika and Future Threats Grand Challenge” has been awarded to a team of experts, led by ISGlobal researcher Krijn Paaijmans, for the development of functional prototypes of electronic mosquito barriers (EMB) that prevent mosquitoes of medical importance (vectors of diseases such as dengue, chikungunya, Zika and malaria) from biting their human hosts. The project’s partners include Elisa Sicuri from ISGlobal, Elies Molins of the Materials Science Institute of Barcelona from the National Research Council of Spain (ICMAB-CSIC), Andreas Rose of Biogents AG, Germany, and Horace Cox of the Vector Control Services of Guyana.
“As it goes in science there are always surprises”, explains Paaijmans. “We (ISGlobal, ICMAB and Biogents) are working on another project aimed at capturing mosquitoes using electrostatics (making mosquitoes 'stick' to a net). But when our postdoc Berta Domenech ran some initial tests we realized that, rather than capturing more mosquitoes, we were actually repelling them. A great finding!”
In fact, preliminary results by the team show that mosquitoes close to an electronic source change their flight pattern and move as far away as possible when the power is turned on. The investigators will use this phenomenon to create a sort of electric shield that protects people from mosquito bites even outdoors and during the day. The project’s main objective is to develop prototype EMBs such as wires, vertical sticks and portable boxes, that prevent mosquitoes from entering public spaces (schools, hospitals, workplaces, terraces) and private spaces (homes and gardens) and target both daytime biting (Aedes species) and nighttime biting mosquitoes (Anopheles, Culex). The project will also seek to develop power-delivery systems adapted to local needs (including solar units for lower and middle income countries), address safety and regulatory issues, test the prototypes in Guyana in real settings, assess the cost of scaling up the production and use of EMBs, and contribute to capacity building in medical entomology in Guyana.
“The problem with insecticides and other vector control tools is that they eventually lead to resistance in mosquitoes”, says Paaijmans. “This prompted us to look for solutions that are not only novel and more environmentally-friendly, but also generalist and evolution-proof”. The additional advantage of this system is that by using a random frequency and intensity of electric pulses it will be impossible for mosquitoes to learn and adapt to the electric field. “If successful, there is no reason to think it cannot be used to repel other arthropod disease vectors such as sand flies (leishmaniasis), tsetse flies (sleeping sickness) and kissing bugs (Chagas disease)”.
Twenty other award nominees were announced by USAID, representing “potentially game changing solutions” to mitigate the impact of Zika virus and focusing on issues such as mosquito control and surveillance, personal and household protection, diagnostics, and community engagement.