Kushwah R B S, Mallick P K, Ravikumar H, Dev V, Kapoor N, Adak T P, Singh O P
National Institute of Malaria Research, New Delhi, India.
J Vector Borne Dis. 2015 Mar;52(1):95-8.
BACKGROUND & OBJECTIVES: Aedes albopictus is one of the vectors for dengue and chikungunya and emergence of pyrethroid resistance in this species could be of a major concern in controlling the vector. This study reports insecticide susceptibility status of Ae. albopictus to DDT and pyrethroids in some Indian populations and status of presence of knockdown resistance (kdr) mutations.
Three to four day old adult female Ae. albopictus collected from Delhi, Gurgaon (Haryana), Hardwar (Uttarakhand), Guwahati (Assam) and Kottayam (Kerala) were bio-assayed with DDT (4%), permethrin (0.75%) and deltamethrin (0.05%) impregnated papers using WHO standard susceptibility test kit. Mosquitoes were PCRgenotyped for F1534C kdr-mutation in the voltage-gated sodium channel (VGSC) gene. DDT and pyrethroid resistant individuals were sequenced for partial domain II, III and IV of VGSC targeting residues S989, I1011, V1016, F1534 and D1794 where kdr mutations are reported in Ae. aegypti.
Adult bioassays revealed varying degree of resistance against DDT among five populations of Ae. albopictus with corrected mortalities ranging between 61 and 92%. Kerala and Delhi populations showed incipient resistance against permethrin and deltamethrin respectively. All other populations were susceptible for both the synthetic pyrethroids. None of the kdr mutations was detected in any of DDT, deltamethrin and permethrin resistant individuals.
INTERPRETATION & CONCLUSION: Ae. albopictus has developed resistance against DDT and there is emergence of incipient resistance against pyrethroids in some populations. So far, there is no evidence of presence of knockdown resistance (kdr) mutation in Ae. albopictus.
白纹伊蚊是登革热和基孔肯雅热的传播媒介之一，该物种对拟除虫菊酯产生抗性可能成为控制该媒介的一个主要问题。本研究报告了印度一些地区白纹伊蚊对滴滴涕和拟除虫菊酯的杀虫剂敏感性状况以及击倒抗性（kdr）突变的存在情况。
使用世卫组织标准敏感性测试试剂盒，对从德里、古尔冈（哈里亚纳邦）、哈德瓦（北阿坎德邦）、古瓦哈蒂（阿萨姆邦）和科塔亚姆（喀拉拉邦）采集的3至4日龄成年雌性白纹伊蚊进行生物测定，使用浸渍有4%滴滴涕、0.75%氯菊酯和0.05%溴氰菊酯的纸片。对蚊子的电压门控钠通道（VGSC）基因中的F1534C kdr突变进行PCR基因分型。对滴滴涕和拟除虫菊酯抗性个体的VGSC部分结构域II、III和IV进行测序，靶向埃及伊蚊中报告有kdr突变的S989、I1011、V1016、F1534和D1794位点。
成虫生物测定显示，五个白纹伊蚊种群对滴滴涕的抗性程度不同，校正死亡率在61%至92%之间。喀拉拉邦和德里种群分别对氯菊酯和溴氰菊酯表现出初期抗性。所有其他种群对这两种合成拟除虫菊酯均敏感。在任何滴滴涕、溴氰菊酯和氯菊酯抗性个体中均未检测到kdr突变。
白纹伊蚊已对滴滴涕产生抗性，一些种群中出现了对拟除虫菊酯的初期抗性。到目前为止，没有证据表明白纹伊蚊存在击倒抗性（kdr）突变。
