While sweet foods are the downfall of many humans, they may signal an even greater risk to our bloodsucking friends, the mosquitoes, which seem to have their own sweet tooth. This is because scientists recently invented an aromatic cocktail derived from plant nectars that attract the insects to feed on pesticide-laced poison.
After just two weeks of testing, mosquito populations in an initial field trial plummeted by nearly sixty-six percent, researchers reported. If successful in larger trials, the new approach can be commercialized in as little as one year.
Every year, around seven hundred and twenty-five thousand people die from mosquito-caused blood-borne diseases such as malaria, according to the Bill and Melinda Gates Foundation. Efforts to reduce mosquito populations through spraying insecticides across wide areas or distributing insecticide-containing bed netting have helped in some places.
But many mosquitoes have evolved resistance to certain insecticides. And, to make matters worse, widespread insecticide overuse has contaminated soils and streams, wreaking having on beneficial insects, such as bees, pollinators, and predators that consume pests like mosquitoes.
To avoid these issues, Agenor Mafra-Neto, a chemist and CEO of ISCA Technologies in Riverside, CA, wondered whether or not using a special type of bait might target mosquitoes more directly. He and colleagues from several universities collected a variety of sweet-smelling flowers and other nectar-producing plants. They used a technique known as gas chromatography to separate and identify the odor compounds.
Then they exposed mosquito antennae to thousands of the compounds to see which may or may not have a biological effect. At the same time, they also eliminated scents that attracted bees. Once they settled on a combination of twenty compounds, they added mosquito-killing poison, such as pyrethroids, to the mix.
“There’s a lot of promise there,” says Edmund Norris, an entomologist at Iowa State University in Ames, who attended the presentation. Dan Strickman, a vector control program manager at the Gates Foundation, adds that if further trials prove equally successful, the new approach will have the unique advantage over many mosquito control approaches as it may work both indoors and outdoors.