The entomological impact of passive metofluthrin emanators against indoor aedes aegypti: a randomized field trial

Devine, Gregor J., Vazquez-prokopec, Gonzalo M., Bibiano-Marín, Wilbert, Pavia-Ruz, Norma, Che-Mendoza, Azael, Medina-Barreiro, Anuar, Villegas, Josue, Gonzalez-Olvera, Gabriela, Dunbar, Mike W., Ong, Oselyne, Ritchie, Scott A., Churcher, Thomas S., Kirstein, Oscar D., and Manrique-Saide, Pablo (2021) The entomological impact of passive metofluthrin emanators against indoor aedes aegypti: a randomized field trial. PLoS Neglected Tropical Diseases, 15 (1). e0009036.

[img]
Preview
PDF (Published Version) - Published Version
Available under License Creative Commons Attribution.

Download (1MB) | Preview
View at Publisher Website: https://doi.org/10.1371/journal.pntd.000...
 
14
676


Abstract

Background: In the absence of vaccines or drugs, insecticides are the mainstay of Aedes-borne disease control. Their utility is challenged by the slow deployment of resources, poor community compliance and inadequate household coverage. Novel application methods are required.

Methodology and principal findings: A 10% w/w metofluthrin “emanator” that passively disseminates insecticide from an impregnated net was evaluated in a randomized trial of 200 houses in Mexico. The devices were introduced at a rate of 1 per room and replaced at 3-week intervals. During each of 7 consecutive deployment cycles, indoor resting mosquitoes were sampled using aspirator collections. Assessments of mosquito landing behaviours were made in a subset of houses. Pre-treatment, there were no differences in Aedes aegypti indices between houses recruited to the control and treatment arms. Immediately after metofluthrin deployment, the entomological indices between the trial arms diverged. Averaged across the trial, there were significant reductions in Abundance Rate Ratios for total Ae. aegypti, female abundance and females that contained blood meals (2.5, 2.4 and 2.3-times fewer mosquitoes respectively; P<0.001). Average efficacy was 60.2% for total adults, 58.3% for females, and 57.2% for blood-fed females. The emanators also reduced mosquito landings by 90% from 12.5 to 1.2 per 10-minute sampling period (P<0.05). Homozygous forms of the pyrethroid resistant kdr alleles V410L, V1016L and F1534C were common in the target mosquito population; found in 39%, 24% and 95% of mosquitoes collected during the trial.

Conclusions/Significance: This is the first randomized control trial to evaluate the entomological impact of any volatile pyrethroid on urban Ae. aegypti. It demonstrates that volatile pyrethroids can have a sustained impact on Ae. aegypti population densities and human-vector contact indoors. These effects occur despite the presence of pyrethroid-resistant alleles in the target population. Formulations like these may have considerable utility for public health vector control responses.

Item ID: 67013
Item Type: Article (Research - C1)
ISSN: 1935-2735
Copyright Information: © 2021 Devine et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Date Deposited: 09 May 2022 03:30
Downloads: Total: 676
Last 12 Months: 6
More Statistics

Actions (Repository Staff Only)

Item Control Page Item Control Page