Insecticide resistance in Anopheles arabiensis from Ethiopia (2012-2016): a nationwide study for insecticide resistance monitoring

Between 2012 and 2016, resistance status of An. arabiensis was assessed annually during the long rainy seasons in study sites from seven of the nine regions in Ethiopia. Insecticide resistance levels were measured with WHO susceptibility tests and CDC bottle bioassays using insecticides from four chemical classes (organochlorines, pyrethroids, organophosphates and carbamates), with minor variations in insecticides tested and assays conducted between years. In selected sites, CDC synergist assays were performed by pre-exposing mosquitoes to piperonyl butoxide (PBO). In 2015 and 2016, mosquitoes from DDT and deltamethrin bioassays were randomly selected, identified to species-level and screened for knockdown resistance (kdr) by PCR. (MapVEu VBP0000211)

2012至2016年间，研究人员于埃塞俄比亚9个行政区域中的7个研究站点，在每年的长雨季对阿拉伯按蚊（An. arabiensis）的抗药性状况开展评估。本次研究采用世界卫生组织（World Health Organization，WHO）敏感性试验与美国疾病控制与预防中心（Centers for Disease Control and Prevention，CDC）瓶式生物测定法，针对4类化学药剂（有机氯类、拟除虫菊酯类、有机磷类及氨基甲酸酯类）检测蚊虫抗药性水平，各年度的检测药剂选择与实验操作存在细微差异。在部分选定的研究站点中，研究人员通过将蚊虫预先暴露于胡椒基丁醚（piperonyl butoxide，PBO）的方式，完成CDC增效剂生物测定。2015年与2016年，研究人员随机选取经滴滴涕（dichlorodiphenyltrichloroethane，DDT）与溴氰菊酯（deltamethrin）生物测定的蚊虫样本，进行物种水平鉴定，并通过聚合酶链式反应（Polymerase Chain Reaction，PCR）筛查击倒抗性（knockdown resistance，kdr）基因。(MapVEu VBP0000211)