Excerpted from American Chemical Society newsletter August 23rd, 2017
“Conventional chemical insecticides used to control mosquitoes are used as cover sprays, frequently dispersed over wide areas. But this blanket spray approach exposes people and animals to potentially harmful compounds and can kill bees and other beneficial insects. In addition, residues of these sprays can contaminate soils and streams, as well as promote increased pesticide resistance. To overcome these issues, Mafra-Neto of ISCA Technologies and colleagues at several universities sought to create a more targeted approach using an insecticide potion spiked with a blend of semiochemicals, or chemical signals, that mosquitoes can’t resist.”
“The blend of chemicals that we use to attract mosquitoes is so powerful that they will ignore natural plant odors and attractants in order to get to our formulation,” says Agenor Mafra-Neto, Ph.D. “From a mosquito’s point of view, it’s like having an irresistible chocolate shop on every corner. The product is so seductive that they will feed on it almost exclusively, even when it contains lethal doses of insecticide.”
The resulting product, which is called Vectrax®, is a slow-release formula for use indoors or outdoors. It can be applied as a spray, which produces 1- to 5-millimeter dollops on vegetation or building eaves, or as a semi-solid, caulk-like gel on cracks or holes in outdoor structures. Because the mosquitoes visit and manipulate the dollops, they receive precise doses of the insecticide, and thus are more effectively controlled. Unlike with traditional blanket sprays, nearby surfaces can remain insecticide free.
The researchers are conducting field tests in Tanzania, an African nation where 93 percent of the population is at risk for malaria. In preliminary results, they found that mosquito populations plunged by two-thirds in just two weeks in Vetrax-treated communities compared to untreated ones.