Mosquitoes inhabit various regions of the world, and more than 3,000 species of mosquitoes have been identified. Some of them are vectors of various diseases, such as malaria, yellow fever or dengue fever. According to the World Health Organization, 627,000 people died from malaria in 2020.
It is to control the reproduction of mosquitoes that researcher Dinarte Vasconcelos developed a technical solution within the scope of his doctoral thesis. “My research aims to produce an economically viable solution consisting of an array of sensors that can detect mosquitoes and differentiate them from other insects,” said the researcher. The research project was advised by professors Nuno Nunes and João Pedro Gomes from the Instituto Superior Técnico and researchers from the Institute of Interaction Technologies (ITI) and the Institute of Systems and Robotics (ISR), respectively.
Initially, the team tested microphones that capture the sound of mosquitoes beating their wings. “Because the frequency of wing flapping varies from species to species, the pattern of the species can be identified through the microphone,” explains Dinarte Vasconcelos. However, this method only allows measurements over short distances, and the system is not prepared to deal with background noise. By including an infrared optical sensor, it is possible to increase the coverage of the system and make it immune to ambient noise. However, the presence of multiple insects requires the use of artificial intelligence to achieve better results. “We need a database to identify which detected insects are mosquitoes,” he added.
Under favorable conditions, a female mosquito can hatch between 100 and 200 eggs in seven days, which is why the prototype had to be able to distinguish males from females. “Our laboratory tests, carried out in collaboration with the Natural History Museum of Funchal, showed that our system correctly identified the species and sex of more than 90 percent of the mosquitoes,” says Dinarte Vasconcelos. Dinarte and team conducted further tests in Thailand in collaboration with Mahidol University, where malaria-transmitting mosquitoes –Aedes mosquito and Anopheles, exist. The researchers conducted the experiments near the Rajanagarindra International Center for Tropical Diseases (RTIC). Here, the team placed light and dry ice traps to attract mosquitoes. They designed these tests to calibrate sensors, identify problems and improve detection in the wild.
Once complete, the prototype will transmit data via radio frequency to health authorities to transmit data, since it is more energy efficient than WiFi, allowing real-time mapping of mosquito presence. In this sense, the Institute of Interactive Technologies, University College London and the Madeira Health Authority have signed a research agreement to develop a surveillance system in Madeira.
In the future, the researchers intend to continue developing the technique so that it can distinguish mosquitoes from other insects. In addition to serving its original purpose, researchers can use the same technique to monitor other insect species of particular interest, such as honeybees and other pollinators, whose populations have persisted over the past few years.