Susceptibility/resistance of selected insecticides in Anopheles mosquitoes of district Mirpur Khas, Sindh, Pakistan
Muhammad Hammad, Adil Bhatti, Muhammad Uzair Mukhtar, Ali Arslan, Shumaila Mushtaq, Arqam Bakhtyar zaki
Vector control is an effective way of reducing malaria transmission. The main vector control methods include the use of insecticide-treated bed nets and indoor residual spraying (IRS) and larviciding. Pyrethroids represent the only class of insecticides approved for treating bed nets and currently used in malaria control strategy. However, insecticide resistance, in particular pyrethroid cross-resistance, is a challenge facing malaria vector control in district Mirpur Khas. Anopheles mosquitoes were collected from four malaria surveillance sites i.e Goth Limoon, Goth Bhoorji, Goth Ahmed Khan, and Goth Kamal Khan Kapri of district Mirpur Khas Pakistan. The mosquitoes were collected from field and identified using morphological keys. Field collected adult female mosquitoes Anopheles subpictus were tested for susceptibility using standard WHO protocols, susceptibility test kits and insecticide treated papers. Anopheles subpictus were exposed to various diagnostic doses of three pyrethroids (Deltamethrin, Lambda-cyhalothrin, and Permethrin), one organophosphate (malathion), and one chlorinated hydrocarbon (DDT), showed a range of mortalities in various localities of district Mirpur Khas. Anopheles subpictus was resistant to four out of five insecticides in all four localities. Results of test done on Anopheles subpictus, against diagnostic dose of 4 % DDT shown percentage mortality ranged from 50.44 % to 100 %. Anopheles subpictus, shown no resistance against 5 % Malathion with mortality rate of 100 %.Test results against 0.05 % Deltamethrin diagnostic dose showed resistance in Anopheles subpictus with percentage mortality ranged from 64.75 % to 100 %. Wild caught female Anopheles subpictus showed percentage mortality ranged from 56.89 % to 77.40% against 0.05 % Lambdacyhalothrin, while against 0.75 % Permethrin the species were resistant with percentage mortality ranged from 54.78 % to 67.21 % in all four localities. This current survey of insecticide resistance in Anopheles species provides baseline information for monitoring resistance in district Mirpur Khas and highlights the need for routine resistance surveillance as an integral part of the vector control programme.
Muhammad Hammad, Adil Bhatti, Muhammad Uzair Mukhtar, Ali Arslan, Shumaila Mushtaq, Arqam Bakhtyar zaki. Susceptibility/resistance of selected insecticides in Anopheles mosquitoes of district Mirpur Khas, Sindh, Pakistan. J Entomol Zool Stud 2015;3(6):321-325.