Institut de Recherche en Sciences de la Santé / Centre Muraz, Bobo-Dioulasso, Burkina Faso; Université Nazi Boni, Bobo-Dioulasso, Burkina Faso.
Institut de Recherche en Sciences de la Santé / Centre Muraz, Bobo-Dioulasso, Burkina Faso.
Acta Trop. 2019 Sep;197:105054. doi: 10.1016/j.actatropica.2019.105054. Epub 2019 Jun 5.
Vector control constitutes a fundamental approach in reducing vector density and the efficient option to break malaria transmission in Africa. Malaria vectors developed resistance to almost all classes of insecticides recommended by WHO for vector control in most places of African countries and may compromise the vector control strategies. This study updated the resistance status of Anopheles gambiae complex populations to insecticides recommended for vector control in the western part of Burkina Faso. Insecticide susceptibility bioassays were performed on seven natural populations of An. gambiae complex from western Burkina Faso in the 2016 rainy season using the WHO protocol. Biochemical assays were carried out according to the WHO protocol on the same populations to estimate detoxifying enzymes activities including non-specific esterases (NSEs), oxidases (cytochrome P450) and Glutathione-S-Transferases (GSTs). Polymerase Chain Reactions (PCRs) were performed for the identification of the An. gambiae complex species as well as the detection of kdr-west and ace-1 mutations. Susceptibility bioassays showed that An. gambiae complex was multi-resistant to pyrethroids, DDT and carbamates in almost all areas. The mortality rates ranged from 10 to 38%, 2.67 to 59.57% and 64.38 to 98.02% for Deltamethrin, DDT and Bendiocarb respectively. A full susceptibility (100%) to an organophosphate, the Chlorpyrifos-methyl, was observed at the different sites. Three (3) species of the An. gambiae complex were identified: An. gambiae s.s, An. coluzzii and An. arabiensis. The frequencies of the kdr-w mutation were highly widespread (0.66 to 0.98) among the three species of the complex. The ace-1 mutation was detected at low frequencies (0 to 0.12) in An. gambiae s.s and An. coluzzii. A high level of GSTs and NSEs were observed within the different populations of the An. gambiae complex. Several mechanisms of insecticide resistance were found simultaneously in the same populations of An. gambiae complex conferring high multi-resistance to DDT, Carbamate and Pyrethroids. The full susceptibility of An. gambiae complex to organophosphates is a useful data for the national malaria control program in selecting the most appropriate products to both maintain the effectiveness of vector control strategies and best manage insecticide resistance as well as developing new alternative strategies for the control of major malaria vectors in Burkina Faso.
病媒控制构成降低病媒密度和打破非洲疟疾传播的基本方法。疟疾媒介对世界卫生组织推荐用于大多数非洲国家病媒控制的几乎所有杀虫剂类别都产生了抗药性，这可能会影响病媒控制策略。本研究更新了布基纳法索西部推荐用于病媒控制的冈比亚按蚊复合体种群对杀虫剂的抗药性状况。2016 年雨季，使用世界卫生组织方案，在布基纳法索西部的七个冈比亚按蚊复合体自然种群中进行了杀虫剂敏感性生物测定。根据世界卫生组织方案，对同一人群进行了生化测定，以估计解毒酶活性，包括非特异性酯酶（NSE）、氧化酶（细胞色素 P450）和谷胱甘肽-S-转移酶（GSTs）。聚合酶链反应（PCR）用于鉴定冈比亚按蚊复合体物种以及检测 kdr-west 和 ace-1 突变。敏感性生物测定显示，冈比亚按蚊复合体在几乎所有地区对拟除虫菊酯、滴滴涕和氨基甲酸酯均具有多抗性。溴氰菊酯、滴滴涕和苯氧威的死亡率分别为 10%至 38%、2.67%至 59.57%和 64.38%至 98.02%。在不同地点观察到对有机磷杀虫剂毒死蜱-甲基的完全敏感性（100%）。鉴定出三种（3）种冈比亚按蚊复合体：冈比亚按蚊 s.s、冈比亚按蚊 coluzzii 和冈比亚按蚊 arabiensis。kdr-w 突变的频率在复合体的三种物种中广泛存在（0.66 至 0.98）。在冈比亚按蚊 s.s 和冈比亚按蚊 coluzzii 中检测到 ace-1 突变的频率较低（0 至 0.12）。在冈比亚按蚊复合体的不同种群中观察到高水平的 GSTs 和 NSEs。在冈比亚按蚊复合体的同一种群中同时发现了几种杀虫剂抗性机制，导致滴滴涕、氨基甲酸酯和拟除虫菊酯的高度多抗性。冈比亚按蚊复合体对有机磷的完全敏感性是国家疟疾控制规划的有用数据，可用于选择最合适的产品，以维持病媒控制策略的有效性，并最好地管理杀虫剂抗性，以及为布基纳法索的主要疟疾媒介控制开发新的替代策略。
