Centre Suisse de Recherche Scientifique en Côte d'Ivoire (CSRS), Abidjan, Côte d'Ivoire.
Université Nangui Abrogoua, Abidjan, Côte d'Ivoire.
Biomed Res Int. 2018 Oct 8;2018:2874160. doi: 10.1155/2018/2874160. eCollection 2018.
Insecticide resistance monitoring of the malaria vectors to different classes of insecticides is necessary for resistance management. Malaria vector control management approaches are essentially based on IRS and LLINs. However, insecticide resistance is caused by several sources of selection and in case the selection pressure is from agricultural practices, then measures need to be taken to avoid a failure of the control methods put in place. The current study was undertaken to monitor the susceptibility of vectors to different classes of insecticides in areas of varying agrochemical use patterns.
A survey to determine the agricultural chemical use pattern was undertaken in ten localities across Côte d'Ivoire. In addition, WHO susceptibility tests were carried out on adults mosquitoes emerging from collected larvae from the sites surveyed. Four insecticides from each class of the four classes of insecticides were evaluated using the standard susceptibility test methods. Furthermore, the target site mutations involved in resistance mechanisms were identified following the Taqman assay protocols and mosquito species were identified using SINE-PCR.
The mortalities of all the populations were similar regardless of the pesticide use pattern. The vectors were resistant to DDT, deltamethrin, and bendiocarb in all localities. In contrast, mosquitoes showed high susceptibility to malathion. High frequency of the Kdr-West gene allele was observed (70-100%). A single Kdr-East mutation was identified in a mosquito that harboured both Ace-1 and Kdr-West genes.
Cultivated marshlands representing good habitats for mosquito development may deeply contribute to the selection of resistance genes given the intensive use of agrochemical for crop protection. In view of these, special attention must be given to them to mitigate mosquito resistance to insecticides.
为了进行抗药性管理，有必要监测疟疾媒介对不同类别的杀虫剂的抗药性。疟疾媒介控制管理方法主要基于 IRS 和 LLINs。然而，杀虫剂抗药性是由多种选择源引起的，如果选择压力来自农业实践，那么就需要采取措施避免已实施的控制方法失败。本研究旨在监测不同农业化学使用模式地区的媒介对不同类别的杀虫剂的敏感性。
在科特迪瓦的十个地点进行了一项调查，以确定农业化学品的使用模式。此外，在从调查地点收集的幼虫中出现的成年蚊子上进行了世界卫生组织的敏感性测试。使用标准敏感性测试方法评估了来自四类杀虫剂中的每类的四种杀虫剂。此外，根据 Taqman 分析协议确定了参与抗药性机制的靶位突变，并使用 SINE-PCR 鉴定了蚊子种类。
无论农药使用模式如何，所有种群的死亡率都相似。在所有地点，媒介对滴滴涕、溴氰菊酯和苯氧威均具有抗药性。相比之下，蚊子对马拉硫磷表现出高敏感性。观察到 Kdr-West 基因等位基因的高频率（70-100%）。在同时携带 Ace-1 和 Kdr-West 基因的蚊子中鉴定出一个单一的 Kdr-East 突变。
鉴于密集使用农用化学品来保护作物，作为蚊子发育良好栖息地的人工湿地可能会对选择抗药性基因产生深远影响。鉴于这些，必须特别关注它们，以减轻蚊子对杀虫剂的抗药性。
