Location: Mosquito and Fly ResearchTitle: Potential for utilization of spatial repellents in mosquito control interventions Author
Submitted to: Journal of the American Chemical Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/24/2018
Publication Date: N/A
Interpretive Summary: This was an effort to evaluate a relatively new technology, spatial repellents, for the control of mosquitoes. The new technology differs from the use of topical repellents in that they are not applied to the host and the mosquitoes do not need to land on them to cause them to not bite. In contrast to topical repellents, spatial repellents are airborne vapors which interfere with the female mosquito's ability to locate the host and obtain a blood-meal. In this study conducted at our USDA-ARS, CMAVE facility, located in Gainesville, FL we tested the efficacy of several commercial products and one experimental device to prevent mosquito-host contact. The technology looks promising, but much work remains to develop better passive delivery devices of effective active ingredients.
Technical Abstract: The use of spatial repellents in mosquito control interventions as either an alternative or complementary tool to current technologies (indoor residual sprays, insecticide-treated bed nets, area-wide space sprays, topical repellents) has been proposed by various authors. This is due partially to mosquito behavior changes such that there appears to be an increase in malaria transmission outdoors, and partially due to increased resistance to currently used insecticides. In this paper we review some general literature on what spatial repellents are, how they theoretically function and product availability. Many commercial spatial repellent products exist, but few studies on their efficacy have been reported. We report on semi-field studies we conducted to determine the efficacy of several emanators of transfluthrin, 3 commercially available and one experimental. Both mortality and repellency effects were evaluated. We conclude that dose of active ingredient and delivery platform affect efficacy. The experimental emanator, the Hessian strip, was the most effective. Based on these and other studies we have been conducting with other active ingredients and delivery platforms we feel that spatial repellents can be effective at reducing mosquito-host contact. One concern, however, is whether or not their use will be accepted by the public. In a study conducted in Cambodia, some residents expressed a willingness to use spatial repellents again, but not as a substitute for bed nets.