Francis Sheena, Saavedra-Rodriguez Karla, Perera Rushika, Paine Mark, Black William C, Delgoda Rupika
Natural Products Institute, Faculty of Science and Technology, University of the West Indies, Mona, Jamaica.
Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America.
PLoS One. 2017 Jun 26;12(6):e0179673. doi: 10.1371/journal.pone.0179673. eCollection 2017.
The emergence of novel diseases spread by the Aedes aegypti mosquito in Jamaica and the Caribbean, has prompted studies on insecticide resistance towards effective management of the vector. Though Jamaica has been using the organophosphate insecticide malathion in its vector control program for more than 30 years, resistance to the pesticide has not been tested in over a decade. We analyzed resistance to malathion and the pyrethroid insecticide, permethrin on mosquitoes collected across St. Andrew, Jamaica, and analyzed the molecular basis of resistance. The Center for Disease Control (CDC) bioassay revealed that Ae. aegypti mosquitoes from St. Andrew, Jamaica were resistant to permethrin (15 μg/bottle) with mortalities at 0-8% at 30 minute exposure time, while contact with malathion (50 μg/bottle) revealed ≤ 50% mortality at 15 minutes, which increased to 100% at 45 minutes. The standard susceptible New Orleans (NO) strain exhibited 100% mortality within15 minutes. The activities of multifunction oxidases and p-nitro phenyl-acetate esterases were significantly greater in most Jamaican populations in comparison to the NO strain, while activities of glutathione-S-transferase, acetylcholinesterase, α-esterase and ß-esterase activity were relatively equal, or lower than that of the control strain. The frequency of knockdown resistance mutations in the voltage dependent sodium channel gene were measured. All collections were fixed for Cys1,534 while 56% of mosquitoes were Ile1,016/Val1,016 heterozygotes, and 33% were Ile1,016 homozygotes. Aedes aegypti from St. Andrew Jamaica are resistant to permethrin with variations in the mode of mechanism, and possibly developing resistance to malathion. Continued monitoring of resistance is critically important to manage the spread of the vector in the country.
在牙买加和加勒比地区，由埃及伊蚊传播的新型疾病的出现，促使人们开展关于杀虫剂抗性的研究，以有效控制病媒。尽管牙买加在其病媒控制项目中使用有机磷杀虫剂马拉硫磷已有30多年，但对该杀虫剂的抗性在十多年来一直未进行检测。我们分析了牙买加圣安德鲁地区采集的蚊子对马拉硫磷和拟除虫菊酯类杀虫剂氯菊酯的抗性，并分析了抗性的分子基础。疾病控制中心（CDC）生物测定显示，来自牙买加圣安德鲁的埃及伊蚊对氯菊酯（15微克/瓶）具有抗性，在30分钟暴露时间下死亡率为0 - 8%，而接触马拉硫磷（50微克/瓶）在15分钟时死亡率≤50%，在45分钟时增至100%。标准易感新奥尔良（NO）品系在15分钟内死亡率达100%。与NO品系相比，大多数牙买加种群中多功能氧化酶和对硝基苯乙酸酯酶的活性显著更高，而谷胱甘肽 - S - 转移酶、乙酰胆碱酯酶、α - 酯酶和β - 酯酶的活性相对相当或低于对照品系。测定了电压依赖性钠通道基因中击倒抗性突变的频率。所有采集样本中Cys1,534位点均为固定型，而56%的蚊子为Ile1,016/Val1,016杂合子，33%为Ile1,016纯合子。来自牙买加圣安德鲁的埃及伊蚊对氯菊酯具有抗性，抗性机制模式存在差异，并且可能正在对马拉硫磷产生抗性。持续监测抗性对于控制该国病媒的传播至关重要。
