Insecticide resistance status and mechanisms in Aedes aegypti populations from Senegal.
Insecticide resistance status and mechanisms in Aedes aegypti populations from Senegal.
复制标题
DOI：
10.1371/journal.pntd.0009393
复制
发表时间：
2021-05
影响因子：
3.8
通讯作者：
Diallo M
中科院分区：
文献类型：
--
作者：
Sene NM;Mavridis K;Ndiaye EH;Diagne CT;Gaye A;Ngom EHM;Ba Y;Diallo D;Vontas J;Dia I;Diallo M
埃及伊蚊是非洲虫媒病毒的主要流行媒介。在塞内加尔，控制活动主要限于缓解流行病，可获得的埃博拉疫情信息有限。埃及伊蚊种群。更好地理解当前的Ae。实施有效的媒介控制策略需要埃及伊蚊对各种杀虫剂的敏感性状况和涉及的相关抗性机制。本研究着重于抗药性的检测，并揭示了Ae的相关机制。来自塞内加尔的埃及人种群。对Ae进行生物测定。塞内加尔九个地区(Matam、Louga、Barkedji、Ziguinchor、Mbour、Fatick、达喀尔、Kédougou和Touba)的埃及成年人。按照世卫组织的标准方案，蚊子接触了四类杀虫剂。通过对拟除虫菊酯靶位抗性突变(V1016G、V1016I、F1534C和S989P)的基因分型和关键解毒基因(CYP6BB2、CYP9J26、CYP9J28、CYP9J32、CYP9M6、CCEae3a和GSTD4)的基因表达水平的测定，探讨了拟除虫菊酯的抗性机制。除马谭县(北部地区)的种群外，其余种群均对滴滴涕和氨基甲酸酯类具有抗性。在所有地区的蚊子中都发现了对氯氰菊酯的抗药性。除BarkéDji和Touba外，所有种群都对0.75%二氯菊酯敏感。仅在南部地区(Kédougou和Ziguinchor)检测到对II型拟除虫菊酯的敏感性。所有蚊种对5%马拉硫磷敏感，但只有凯杜古和马塔姆蚊子对0.8%马拉硫磷敏感。所有种群对0.05%甲基嘧啶磷具有抗性，而来自Louga、Mbour和BarkéDJI的种群对1%杀灭磷也表现出抗性。在基因分型分析中包括的蚊子样本(在>；1500个样本中进行)中没有任何已知的目标位置对拟除虫菊酯抗药性突变。相反，观察到主要解毒基因的高表达(20-70倍)，这表明杀虫剂抗性主要是通过代谢机制调节的。这些数据为支持塞内加尔的登革热病媒控制提供了重要证据。在塞内加尔，就像在大多数非洲国家一样，虫媒病毒流行控制政策依赖于对主要媒介Ae的控制。埃及伊蚊通过杀虫剂的应用。在很大程度上采用了病媒控制战略，但没有关于病媒种群的抗药性机制的信息。我们在这里描述了九艾的抵抗状态。塞内加尔埃及伊蚊种群对四种杀虫剂及其相关机制的影响。我们的发现显示出对氨基甲酸酯的高度抗性，南方种群对拟除虫菊酯的相对易感性，以及有机磷的不同疗效。对拟除虫菊酯的抗性是由与杀虫剂代谢有关的解毒基因的显著过度表达所驱动的。我们的结果有助于更有针对性和更有效地控制Ae。埃及伊蚊种群，从而导致虫媒病毒在塞内加尔流行。
Aedes aegypti is the main epidemic vector of arboviruses in Africa. In Senegal, control activities are mainly limited to mitigation of epidemics, with limited information available for Ae. aegypti populations. A better understanding of the current Ae. aegypti susceptibility status to various insecticides and relevant resistance mechanisms involved is needed for the implementation of effective vector control strategies. The present study focuses on the detection of insecticide resistance and reveals the related mechanisms in Ae. aegypti populations from Senegal. Bioassays were performed on Ae. aegypti adults from nine Senegalese localities (Matam, Louga, Barkedji, Ziguinchor, Mbour, Fatick, Dakar, Kédougou and Touba). Mosquitoes were exposed to four classes of insecticides using the standard WHO protocols. Resistance mechanisms were investigated by genotyping for pyrethroid target site resistance mutations (V1016G, V1016I, F1534C and S989P) and measuring gene expression levels of key detoxification genes (CYP6BB2, CYP9J26, CYP9J28, CYP9J32, CYP9M6, CCEae3a and GSTD4). All collected populations were resistant to DDT and carbamates except for the ones in Matam (Northern region). Resistance to permethrin was uniformly detected in mosquitoes from all areas. Except for Barkédji and Touba, all populations were characterized by a susceptibility to 0.75% Permethrin. Susceptibility to type II pyrethroids was detected only in the Southern regions (Kédougou and Ziguinchor). All mosquito populations were susceptible to 5% Malathion, but only Kédougou and Matam mosquitoes were susceptible to 0.8% Malathion. All populations were resistant to 0.05% Pirimiphos-methyl, whereas those from Louga, Mbour and Barkédji, also exhibited resistance to 1% Fenitrothion. None of the known target site pyrethroid resistance mutations was present in the mosquito samples included in the genotyping analysis (performed in > 1500 samples). In contrast, a remarkably high (20-70-fold) overexpression of major detoxification genes was observed, suggesting that insecticide resistance is mostly mediated through metabolic mechanisms. These data provide important evidence to support dengue vector control in Senegal. In Senegal, as in most African countries, the arbovirus epidemics control policy relies on the control of the main vector Ae. aegypti though insecticide applications. Vector control strategies have been largely adopted without information on the vector populations’ insecticide resistance mechanisms. We profiled here the resistance status of nine Ae. aegypti populations from Senegal to four classes of insecticides and their related mechanisms. Our findings revealed high resistance to carbamates, a relative susceptibility of southern populations to pyrethroids and a variable efficacy of organophosphates. Resistance to pyrethroids was driven by a significant overexpression of detoxification genes linked to insecticide metabolism. Our results contribute towards a more targeted and efficient control of Ae. aegypti populations and thus of arbovirus epidemics in Senegal.