Electrostatic coating enhances bioavailability of insecticides and breaks pyrethroid resistance in mosquitoes

Abstract

Insecticide resistance poses a significant and increasing threat to the control of malaria and other mosquito-borne diseases. We present a novel method of insecticide application based on netting treated with an electrostatic coating that binds insecticidal particles through polarity. Electrostatic netting can hold small amounts of insecticides effectively and results in enhanced bioavailability upon contact by the insect. Six pyrethroid-resistant Anopheles mosquito strains from across Africa were exposed to similar concentrations of deltamethrin on electrostatic netting or a standard longlasting deltamethrin-coated bednet (PermaNet 2.0). Standard WHO exposure bioassays showed that electrostatic netting induced significantly higher mortality rates than the PermaNet, thereby effectively breaking mosquito resistance. Electrostatic netting also induced high mortality in resistant mosquito strains when a 15-fold lower dose of deltamethrin was applied and when the exposure time was reduced to only 5 s. Because different types of particles adhere to electrostatic netting, it is also possible to apply nonpyrethroid insecticides. Three insecticide classes were effective against strains of Aedes and Culex mosquitoes, demonstrating that electrostatic netting can be used to deploy a wide range of active insecticides against all major groups of disease-transmitting mosquitoes. Promising applications include the use of electrostatic coating on walls or eave curtains and in trapping/ contamination devices. We conclude that application of electrostatically adhered particles boosts the efficacy of WHO-recommended insecticides even against resistant mosquitoes. This innovative technique has potential to support the use of unconventional insecticide classes or combinations thereof, potentially offering a significant step forward in managing insecticide resistance in vector-control operations.electrostatic coating | insecticide | resistance management | mosquito | malaria

Direct and indirect effects of predation and parasitism on the Anopheles gambiae mosquito

“…The method used to calculate spore density is described in Additional file 1: Text S1. One female mosquito, at a time, was aspirated from the holding cage and introduced into the exposure cup with the fungus-exposed electrostatic net (or for the control, only the electrostatic net) [27]. The top of the cup was covered with mosquito net and the female was left inside for 10 min.…”

“…Since 2003, entomopathogenic fungi have gained a renewed interest for their potential to control malaria mosquito larvae and adults [22][23][24][25][26]. Many laboratory and field studies have been conducted focusing on improving the delivery of fungal spores to the mosquitoes and the potential to control insecticide-resistant mosquitoes [22,24,[27][28][29]. Multiple strains of Metarhizium anisopliae and B. bassiana have been intensively studied in this regard [18,[22][23][24][25][26][27][28][29][30].…”

MiR-932 Regulates Pyrethroid Resistance inCulex pipiens pallens(Diptera: Culicidae)

“…Mosquitoes transmit a lot of pathogens, causing severe diseases such as malaria, dengue fever, West Nile fever, encephalitis, and filariasis, which threat public health worldwide (Andriessen et al 2015, Fortuna et al 2015, Paredes-Esquivel et al 2015. Recent estimates show that there are about 400 million infections of dengue fever annually around the world (Sood et al 2015).…”

“…In addition, knockdown of CpCPR5 decreased the sensitivity of mosquitoes to deltamethrin in the DS-strain. In conclusion, our study finds a molecular link between miR-932 and CpCPR5 and provides a novel insight into the mechanism of insecticide resistance.Key words: Culex pipiens pallens, pyrethroid, microRNA, CpCPR5Mosquitoes transmit a lot of pathogens, causing severe diseases such as malaria, dengue fever, West Nile fever, encephalitis, and filariasis, which threat public health worldwide (Andriessen et al 2015, Fortuna et al 2015, Paredes-Esquivel et al 2015. Recent estimates show that there are about 400 million infections of dengue fever annually around the world (Sood et al 2015).…”

Priorities for Broadening the Malaria Vector Control Tool Kit

“…The eave tubes contain an insert comprising insecticide treated netting that kills mosquitoes as they attempt to enter the house through the tubes [62,63]. An electrostatic coating on the insert screening allows for the use of powder formulations of insecticides, a delivery method that is highly effective even against resistant mosquitoes [64]. One benefit of the lethal house lure approach is that it is a passive technology that protects everyone sleeping in the house (IRS is a household level intervention but generally does not prevent house entry; LLINS provide personal protection but rarely does everyone in a house use a net).…”