Antibodies. Genes. Bacteria. Artificial Intelligence. Satellites. Drones. New technologies are being deployed in new ways in the fight against dengue. While some are halting the vector in its tracks, others are tackling the dengue virus. Some are already in use; others are experimental. Let’s look at the dengue-fighting technology we can expect to see as we take on this killer virus – and its vector – in 2020.
New approaches based on genes
Our first dengue-fighting technology stops Aedes aegypti mosquitoes infected with the dengue virus from transmitting the virus to humans. Researchers in UC San Diego have transferred genes from the human immune system to pass immunity to all four dengue serotypes to Aedes mosquitoes. Female Aedes are synthetically engineered to have the antibody, which is activated by feeding on blood. The antibody prevents the dengue virus replicating throughout her body, ensuring she can’t pass it on. A gene dissemination system could spread the antibody to wild mosquito populations.
Elsewhere, an article in Science Daily explores our second dengue-fighting technology: gene therapy that can prevent mosquitoes reaching maturity. The technique prevents a steroid hormone that insects require for sexual maturity from reaching the brain. The approach could limit mosquito maturity to somewhere between infancy and adulthood. They would die before they reproduce and remain in or on their food source rather than wander to feed.
The sterile insect technique bites back
Last September, the International Atomic Energy Agency (IAEA) announced a US$ 3.96 million grant from the US Government to overcome some of the challenges of sterile insect technique (SIT). SIT involves rearing, sterilising then releasing large numbers of a target pest into wild populations to suppress their number. It requires the females reared to be separated from the males, which is not easy. The IAEA is rearing Aedes mosquitoes and sterilising them using radiation; this short animation explains how it works. The grant will allow it to develop new ways of separating males from females.
Other projects are also using similar techniques to suppress mosquito populations – including Debug, a project backed by Verily, a subsidiary of Alphabet Inc, which is Google’s parent company. Debug is using the Wolbachia bacteria technique developed by the World Mosquito Program to prevent female Aedes mosquitoes transmitting dengue; it too must rear large numbers of female and release them into wild populations to propagate.
Verily’s dengue-fighting technology, according to the news pages of Harvard Chan, sorts the mosquitoes by sex and optimises releases. The project website describes how sensors, algorithms and innovative engineering sort males from females efficiently using unique aspects of mosquito biology. Verily, it says, is also “building software and monitoring tools to guide each release” and “developing new sensors, traps and software to determine better which areas need to be treated and re-treated”.
Artificial intelligence gets real
A not-for-profit called ‘the Program’ that has recently been awarded a Microsoft AI for Earth grant is also combining Wolbachia with software to optimise releases. An article on the Microsoft website describes how the global research consortium is combining Wolbachia with “data, machine learning, artificial intelligence (AI) and the computation power of the cloud” to create a predictive deep learning model that will determine the best release points “anywhere in the world”.
Another project has turned to AI – to develop real-time risk maps for public-health bodies. ZDNet describes how the Institute of Agrifood Research and Technology (IRTA) in Catalonia, Spain has combined AI, sensors and satellite communications for vector surveillance. Together these dengue-fighting technologies automatically classify mosquitoes – which are caught in traps – according to species, sex, age and their potential for causing infection. The Vectrack system, as it is known, is funded by the EU Horizon 2020 programme.
Maps are not only being used to assess risk but also guide preventative measures, such as eliminating mosquito-breeding sites. Dengue MOsquito Simulation from Satellites (D-MOSS), reports Space for Development, issues alerts for dengue to mobilise local communities while assessing risk under future climate and land‑use change scenarios. Funded by the UK Space Agency’s International Partnership Programme, the project integrates and analyses Earth observation datasets, weather forecasts and a model of water flow to build its maps.
Scientists at Arthur C Clarke Institute for Modern Technologies (ACCIMT) in Sri Lanka are using drones to contain dengue outbreaks, according to local media. The dengue-fighting technology is helping the authorities observe, photograph and even fumigate sites where stagnant water could be found. The ACCIMT website describes a project at the Space Technologies & Applications Division using geographic information systems GIS for niche modelling of dengue fever.
Tackling dengue back down on Earth
Back down to Earth, a Malaysian start-up is tricking Aedes mosquitoes into eating their own eggs. Vulcan Post describes how MN Empire has developed a ‘solar-powered mosquito eliminator’. The dengue-fighting device attracts mosquitoes and encourages them to lay their eggs inside containers filled with a liquid that ensures they never hatch. The female mosquitoes then spread the “organic, odourless and completely safe” solution to other sources of stagnant water.
Meanwhile, EurekAlert! highlights a targeted biological approach that kills mosquito larvae using natural bacteria delivered by the male mosquito while mating. The ‘Trojan Mosquito’ is being developed by a team of undergraduate student researchers at Ben-Gurion University of the Negev in Israel. They tweaked the male mosquito’s gut microbiome to express BTI (Bacillus Thuringiensis Israelensis), which produces a toxin that only kills mosquito larvae. The males mate with females, who transfer the bacteria onto their eggs. The larvae die soon after birth.
In Australia, Bio-Gene Technology has developed an alternative insecticide. Based on a natural compound found in Australia’s eucalypt trees, Flavocide is rapidly toxic to adult mosquitoes. An article in Small Caps describes how Flavocide is a potential new product to address the diminishing effectiveness of current insecticides.
Our final dengue-fighting technology is a skin cream that could protect against dengue. Science Translational Medicine has published a paper on a topical treatment that, when tested on mice recently infected by dengue, elicited an immune reaction at the site of a mosquito bite that restricted the dengue virus’ ability to replicate.
We’d love to hear about your innovations and how they are helping in the fight against dengue. Whether you’re halting the virus in its tracks or eliminating Aedes populations, we’re interested to know more.