Yaméogo Félix, Sombié Aboubacar, Oté Manabu, Saiki Erisha, Sakurai Tatsuya, Wangrawa Dimitri W, McCall Philip J, Weetman David, Kanuka Hirotaka, Badolo Athanase
Laboratoire d'Entomologie Fondamentale et Appliquée, Université Joseph Ki-Zerbo, Ouagadougou, Burkina Faso.
Center for Medical Entomology, The Jikei University School of Medicine, Tokyo, Japan.
PLoS Negl Trop Dis. 2024 Dec 2;18(12):e0012138. doi: 10.1371/journal.pntd.0012138. eCollection 2024 Dec.
Resistance to insecticides is spreading among populations of Aedes aegypti, the primary vector of important human arboviruses. The escalating insecticide resistance poses a significant threat to dengue vector control, with an expanding number of countries affected by the disease. To gain a deeper insight into the evolution of insecticide resistance, it is essential to have longitudinal surveillance results, which are currently lacking, particularly from African Ae. aegypti populations. Here we report on three-years of surveillance of Ae. aegypti susceptibility to insecticide resistance phenotypes and associated kdr mutations in Burkina Faso, a country with regular dengue outbreaks.
Ae. aegypti susceptibility to insecticides and the V410L, V1016I, and F1534C kdr target site mutations linked to pyrethroid insecticide resistance were monitored in Ouagadougou from 2016 to 2018. Larvae were collected from artificial containers at two sites and reared to adulthood in an insectary. Bioassays were conducted on female adults, along with a laboratory-susceptible strain, following standard WHO protocols. Allele-specific PCR genotyping assays were utilized to identify the V410L, V1016I, and F1534C kdr pyrethroid target site mutations.
Bioassays revealed a high level of resistance to permethrin and deltamethrin that progressively increased over the three-year period in both localities. The 1534C mutation was nearly fixed throughout the three years at each locality, and while the closely-related 410L and 1016I mutations did not vary between localities, their frequency notably increased from 2016 to 2018. Interestingly, Ae. aegypti populations in both areas remained susceptible to bendiocarb, fenitrothion, and malathion. Modelling the mortality data further confirmed the escalating resistance trend over the years and emphasized the significant role played by the three kdr mutations in conferring resistance to pyrethroids.
Mortality rates indicate that Ae. aegypti populations from Ouagadougou are becoming increasingly resistant to pyrethroid insecticides, likely due to an increase in the frequencies of the 410L and 1016I kdr mutations. Organophosphate insecticides are likely to be better alternative options for control.
埃及伊蚊是重要人类虫媒病毒的主要传播媒介，其种群对杀虫剂的抗性正在蔓延。不断升级的杀虫剂抗性对登革热媒介控制构成重大威胁，受该疾病影响的国家数量不断增加。为了更深入了解杀虫剂抗性的演变，获得纵向监测结果至关重要，而目前这方面的数据缺乏，尤其是来自非洲埃及伊蚊种群的数据。在此，我们报告了在布基纳法索对埃及伊蚊进行的三年监测情况，该国经常爆发登革热。
2016年至2018年期间，在瓦加杜古监测了埃及伊蚊对杀虫剂的敏感性以及与拟除虫菊酯类杀虫剂抗性相关的V410L、V1016I和F1534C kdr靶位点突变。在两个地点从人工容器中收集幼虫，并在昆虫饲养室饲养至成虫。按照世界卫生组织标准协议，对雌性成虫以及实验室敏感品系进行生物测定。利用等位基因特异性PCR基因分型测定法鉴定V410L、V1016I和F1534C kdr拟除虫菊酯靶位点突变。
生物测定显示，在这两个地点，对氯菊酯和溴氰菊酯的抗性水平较高，且在三年期间逐渐增加。1534C突变在各地点三年内几乎固定，虽然密切相关的410L和1016I突变在不同地点之间没有差异，但其频率从2016年到2018年显著增加。有趣的是，两个地区的埃及伊蚊种群对残杀威、杀螟硫磷和马拉硫磷仍敏感。对死亡率数据进行建模进一步证实了多年来抗性不断升级的趋势，并强调了三个kdr突变在赋予对拟除虫菊酯抗性方面所起的重要作用。
死亡率表明，瓦加杜古的埃及伊蚊种群对拟除虫菊酯类杀虫剂的抗性越来越强，这可能是由于410L和1016I kdr突变频率增加所致。有机磷杀虫剂可能是更好的控制替代选择。
