Hernandez Jonathan R, Lee Han-Jung, Vigilant Maximea E, Crawford Scott, Pietrantonio Patricia V
Department of Entomology, Texas A&M University, College Station, TX, USA.
Mosquito and Vector Control Division, Harris County Public Health, Houston, TX, USA.
Pest Manag Sci. 2025 Feb;81(2):923-936. doi: 10.1002/ps.8495. Epub 2024 Oct 29.
Females of Aedes aegypti transmit emerging arboviruses including Zika, dengue, yellow fever, and chikungunya. Control of these adult mosquitoes heavily relies on synthetic insecticides, including pyrethroids. However, insecticide resistance development in populations poses a significant challenge to vector control, particularly from knockdown resistance (kdr) mutations in the voltage-gated sodium channel (VGSC), the target of pyrethroids. This study investigated the field efficacy of Permanone, a pyrethroid-based insecticide, against Ae. aegypti by assessing the impact of three common kdr mutations (V410L, V1016I, F1534C) on mosquito survival under a real operational mosquito control scenario, by quantifying the pesticide delivered in the field.
Field cage tests (FCTs) were conducted while conducting a realistic mosquito control application. Female mosquitoes from six operational areas from Harris County, TX, USA were exposed to Permanone delivered with a handheld sprayer. Permanone deposited near the cages was estimated from aluminum boats placed in the field during FCTs using gas chromatography-mass spectrometry (GC-MS). Mortality rates were recorded, and individual mosquitoes were genotyped for kdr mutations. A probit regression model was used to analyze the factors influencing mosquito survivorship. As the distance from the application source route increased, the amount of Permanone deposited decreased, resulting in higher survivorship frequency of Ae. aegypti females with the triple-resistant kdr genotype (LL/II/CC). The L allele at the 410-site significantly contributed to an increased resistance level when co-occurring with other kdr mutations.
This study linked the survival probabilities of mosquitoes with different kdr genotypes, and the amount of pesticide they received in the field. Pesticide quantification, control efficacy results and genotyping allowed us to empirically determine the impact of genotypic resistance on vector control in the field. © 2024 Society of Chemical Industry.
埃及伊蚊雌蚊传播包括寨卡病毒、登革热、黄热病和基孔肯雅热在内的多种新兴虫媒病毒。对这些成年蚊子的控制严重依赖于合成杀虫剂，包括拟除虫菊酯。然而，种群中杀虫剂抗性的发展对病媒控制构成了重大挑战，特别是电压门控钠通道（VGSC）中的击倒抗性（kdr）突变，而拟除虫菊酯的作用靶点正是该通道。本研究通过评估三种常见的kdr突变（V410L、V1016I、F1534C）在实际蚊虫控制场景下对蚊子存活的影响，并对现场施用的杀虫剂进行定量，来调查基于拟除虫菊酯的杀虫剂Permanone对埃及伊蚊的田间效果。
在进行实际蚊虫控制应用的同时进行了田间网笼试验（FCT）。来自美国德克萨斯州哈里斯县六个作业区的雌蚊被手持式喷雾器喷洒Permanone。在FCT期间，通过气相色谱 - 质谱联用仪（GC - MS）对放置在田间的铝制容器中的Permanone沉积量进行估算。记录死亡率，并对单个蚊子进行kdr突变基因分型。使用概率回归模型分析影响蚊子存活的因素。随着与施药源路线距离的增加，Permanone沉积量减少，导致具有三重抗性kdr基因型（LL/II/CC）的埃及伊蚊雌蚊存活频率更高。当410位点的L等位基因与其他kdr突变同时出现时，显著增加了抗性水平。
本研究将不同kdr基因型蚊子的存活概率与其在田间接受的农药量联系起来。农药定量、控制效果结果和基因分型使我们能够凭经验确定基因型抗性对田间病媒控制的影响。© 2024化学工业协会
