Mosquitoes are a problem, especially when they’re carrying viruses like dengue and zika that they can pass to unsuspecting humans with a bite. Since there’s no vaccine against dengue, public health experts have to focus on controlling the blood-sucking critters themselves. When cities got big, mosquitoes, in search of standing water, took to the sewers to breed, making them harder to monitor. In response to this problem, a team of scientists at Taiwan National Mosquito-Borne Diseases Control Research Center had an idea: send in robots.
It’s a method that’s been tested by other countries, but often with flying robots that keep an eye on the ground below, and not with remote-controlled crawlers that snoop in sewers. In a new study published this week in PLOS Neglected Tropical Diseases, the team dispatched unmanned vehicles underground to scope out and eliminate mosquito larvae that have congregated in ditches under and around Kaohsiung city in southern Taiwan. After all, getting the pests before they develop wings is much easier than trying to catch them in the air.
These multipurpose robots come with a suite of tools, digital cameras, and LED lights that help them visualize the sewer environment, detect mosquito larvae in areas with standing water, and either spray the area with insecticide or blast it with hot water. The wheeled robots crawl at a rate of 5 meters/min (that’s 16 feet each minute). They’re also designed in a way that prevents them from being overturned in areas where it would be difficult for humans to set them right again. The target for these robots are mosquitoes in the genus Aedes, which contain several species that commonly carry infectious tropical disease.
To surveil mosquito activity around the ditches, scientists also set up a series of Gravitraps that can be used to lure and capture female mosquitoes. The team later analyzed these specimens to see where the dengue-positive mosquitoes tend to go. In many ditches where there were high concentrations of dengue-positive mosquitoes, after the robots were deployed, traps around them showed that the positivity rates for dengue dropped (probably because the mosquito population as a whole took a dip as well), indicating that the bots could be a useful tool for disease control and prevention. Of course, they could always be further improved. With better sensors, AI, mobility, and autonomy functions, these robots could become more usable and practical.