Chen Tse-Yu, Smartt Chelsea T, Shin Dongyoung
Florida Medical Entomology Laboratory, Department of Entomology and Nematology, University of Florida, Vero Beach, FL 32962, USA.
Insects. 2021 Jan 14;12(1):71. doi: 10.3390/insects12010071.
, as one of the vectors transmitting several arboviruses, is the main target in mosquito control programs. Permethrin is used to control mosquitoes and get exposed due to its overuse and are now resistant. The increasing percentage of permethrin resistant has become an important issue around the world and the potential influence on vectorial capacity needs to be studied. Here we selected a permethrin resistant (p-s) population from a wild Florida population and confirmed the resistance ratio to its parental population. We used allele-specific PCR genotyping of the V1016I and F1534C sites in the sodium channel gene to map mutations responsible for the resistance. Two important factors, survival rate and vector competence, that impact vectorial capacity were checked. Results indicated the p-s population had 20 times more resistance to permethrin based on LD50 compared to the parental population. In the genotyping study, the p-s population had more homozygous mutations in both mutant sites of the sodium channel gene. The p-s adults survived longer and had a higher dissemination rate for dengue virus than the parental population. These results suggest that highly permethrin resistant populations might affect the vectorial capacity, moreover, resistance increased the survival time and vector competence, which should be of concern in areas where permethrin is applied.
作为传播多种虫媒病毒的媒介之一，是蚊虫控制项目的主要目标。氯菊酯用于控制蚊虫，但由于过度使用而导致接触，现在已经产生抗性。氯菊酯抗性比例的增加已成为全球一个重要问题，对传播能力的潜在影响需要进行研究。在这里，我们从佛罗里达野生种群中选择了一个氯菊酯抗性（p-s）种群，并确认了其相对于亲代种群的抗性比例。我们使用钠通道基因中V1016I和F1534C位点的等位基因特异性PCR基因分型来定位导致抗性的突变。检查了影响传播能力的两个重要因素，即存活率和媒介感染性。结果表明，基于半数致死剂量（LD50），p-s种群对氯菊酯的抗性是亲代种群的20倍。在基因分型研究中，p-s种群在钠通道基因的两个突变位点有更多的纯合突变。p-s成虫存活时间更长，登革病毒传播率高于亲代种群。这些结果表明，高氯菊酯抗性种群可能会影响传播能力，此外，抗性增加了存活时间和媒介感染性，这在使用氯菊酯的地区应引起关注。
