Vector Group, Liverpool School of Tropical Medicine, Pembroke Place, Liverpool L35QA, UK.
Malar J. 2009 Dec 17;8:299. doi: 10.1186/1475-2875-8-299.
Insecticide resistance in malaria vectors is a growing concern in many countries which requires immediate attention because of the limited chemical arsenal available for vector control. The current extent and distribution of this resistance in many parts of the continent is unknown and yet such information is essential for the planning of effective malaria control interventions.
In 2008, a network was established, with financial support from WHO/TDR, to investigate the extent of insecticide resistance in malaria vectors in five African countries. Here, the results of bioassays on Anopheles gambiae sensu lato from two rounds of monitoring from 12 sentinel sites in three of the partner countries are reported.
Resistance is very heterogeneous even over relatively small distances. Furthermore, in some sites, large differences in mortality rates were observed during the course of the malaria transmission season. Using WHO diagnostic doses, all populations from Burkina Faso and Chad and two of the four populations from Sudan were classified as resistant to permethrin and/or deltamethrin. Very high frequencies of DDT resistance were found in urban areas in Burkina Faso and Sudan and in a cotton-growing district in Chad. In areas where both An. gambiae s.s. and Anopheles arabiensis were present, resistance was found in both species, although generally at a higher frequency in An gambiae s.s. Anopheles gambiae s.l. remains largely susceptible to the organophosphate fenitrothion and the carbamate bendiocarb in the majority of the sentinel sites with the exception of two sites in Burkina Faso. In the cotton-growing region of Soumousso in Burkina Faso, the vector population is resistant to all four classes of insecticide available for malaria control.
Possible factors influencing the frequency of resistant individuals observed in the sentinel sites are discussed. The results of this study highlight the importance of standardized longitudinal insecticide resistance monitoring and the urgent need for studies to monitor the impact of this resistance on malaria vector control activities.
在许多国家，蚊虫对杀虫剂的抗药性日益受到关注，由于控制蚊虫的化学武器有限，因此需要立即予以重视。目前，非洲许多地区对这种抗药性的范围和分布尚不清楚，但此类信息对规划有效的疟疾控制干预措施至关重要。
2008 年，在世卫组织/TDR 的财政支持下，建立了一个网络，以调查五个非洲国家的疟疾媒介蚊虫抗药性的程度。在此，报告了来自三个伙伴国家的 12 个监测哨点的两轮监测中，按蚊按蚊按蚊的生物测定结果。
即使在相对较小的距离内，抗药性也非常不均匀。此外，在某些地点，在疟疾传播季节的过程中，死亡率的差异很大。使用世界卫生组织的诊断剂量，来自布基纳法索和乍得的所有种群以及来自苏丹的四个种群中的两个种群被归类为对氯菊酯和/或溴氰菊酯具有抗药性。在布基纳法索和苏丹的城市地区以及乍得的一个棉花种植区发现了很高的滴滴涕抗药性频率。在同时存在冈比亚按蚊和阿拉伯按蚊的地区，两种蚊种都发现了抗药性，尽管在冈比亚按蚊中通常更为普遍。除了布基纳法索的两个地点外，按蚊属蚊虫对有机磷杀虫剂fenitrothion 和氨基甲酸酯 bendiocarb 仍基本敏感。在布基纳法索的棉花种植区 Soumousso ，媒介种群对可用于疟疾控制的所有四类杀虫剂均具有抗药性。
讨论了影响在监测哨点观察到的抗性个体频率的可能因素。本研究结果强调了标准化纵向杀虫剂抗性监测的重要性以及迫切需要研究监测这种抗性对疟疾媒介控制活动的影响。
