U.S. LABORATORY AND FIELD TRIALS OF METOFLUTHRIN (SUMIONE®) EMANATORS FOR REDUCING MOSQUITO BITING OUTDOORS¹

Abstract

Metofluthrin (SumiOne is a novel, vapor-active pyrethroid that is highly effective against mosquitoes. Laboratory and field trials were conducted in the United States to evaluate the mosquito repellent activity of metofluthrin-treated paper substrates ("emanators"). Initial studies were conducted to evaluate the field performance of 900-cm(2) paper fan emanators impregnated with 160 mg metofluthrin, where Aedes canadensis was the predominant species. Emanators reduced landing rates on human volunteers by between 85% and 100% compared to untreated controls. Subsequent tests with 4,000-cm(2) paper strip emanators impregnated with 200 mg metofluthrin were conducted in a wind tunnel as a precursor to conducting field trials using human bait and laboratory-reared Aedes aegypti. Paper strips, which were pre-aged in a fume hood to determine duration of protection, gave 89-91% reductions in landing rates compared with controls. Similar reductions in biting activity were also noted. Following these tests, field trials to assess effect on landing rates were conducted with emanators positioned 1.22 m on either side of volunteers protected from biting by Tyvek suits, with pre- and posttreatment counts being made. In Florida (predominantly Ochlerotatus spp.) 91-95% reductions were noted 10-30 min after emanators were deployed, while in Washington State (mostly Aedes vexans) 95-97% reductions were observed. These results demonstrate that metofluthrin-treated emanators are highly effective at repelling mosquitoes.

The Effects of Sustained Release Metofluthrin on the Biting, Movement, and Mortality of Aedes aegypti in a Domestic Setting

“…Metofluthrin has also been shown, with aspirator collections, to provide spatial repellency to mosquitoes in outdoor shelters without walls 13,14 and in houses. [15][16][17] Furthermore, metofluthrin has significantly reduced landing rates of Aedes species, 8,9 and reduced the number of Aedes albopictus caught in Centers for Disease Control and Prevention (CDC)-type miniature mosquito traps, 18 in field trials. However, these studies failed to elucidate mosquito movement associated with metofluthrin exposure or the fate of mosquitoes after exposure.…”

“…Traditionally, mosquito coils and insecticidal vaporizing mats or liquids have been used to deter mosquitoes from biting, but these products are limited in their use by the requirement for a heat or power source to vaporize their active ingredient, commonly a synthetic pyrethroid such as d-allethrin or prallethrin. [8][9][10] Furthermore, burning mosquito coils release significant amounts of fine particulate matter and volatile organic compounds that may pose an acute and chronic risk to human health. 11 However, studies into the insecticidal activity of norchrysanthemic acid esters with high vapor activity at ambient temperature by Ujiahra and others 12 identified a synthetic pyrethroid insecticide ("metofluthrin") that doesn't require a heating source and was extremely effective at knocking down Culex pipiens pallens in the laboratory.…”

Field Evaluation of the Off! Clip-On Mosquito Repellent (Metofluthrin) AgainstAedes albopictusandAedes taeniorhynchus(Diptera: Culicidae) in Northeastern Florida

“…albopictus, this result supports other previous reports that metoßuthrin-impregnated paper or plastic strips are effective at repelling mosquitoes. Lucas et al (2007) reported that in a Florida Þeld trial with metoßuthrin paper fan emanators provided 95% protection against mosquitoes (Ochlerotatus spp.). Our Þeld test results showed that the repellent device (belt-worn device) provided 79% protection against Ae.…”

“…A two-way randomized block analysis of variance was used to test for treatment effects for each count, subject, and site. Percentages of reduction in landing count or protection from bites were calculated by comparing posttreatment counts with the overall pretreatment count (Lucas et al 2007). …”

“…Spatial insect repellents release an active ingredient in the form of vapor or smoke by using heat or fan dispersal to create a protected area. Metoßuthrin, a vapor-active pyrethroid insecticide, was discovered to be an effective mosquito repellent (Ujihara et al 2004) and is used as an active ingredient against mosquitoes in impregnated paper (Argueta et al 2004;Kawada et al 2004a,b;Lucas et al 2007) and plastic strips (Kawada et al 2005a(Kawada et al ,b, 2006(Kawada et al , 2008. This active ingredient (AI) also has been shown to be an effective spatial mosquito repellent (Kawada et al 2005).…”