ABSTRACT
Abstract:background et objectives:Mosquito control is becoming increasingly difficult because of the developmentof resistance in vectors to conventional insecticides. The resistance in vectors warrants development of newer insecticides for mosquito control besides use of other counter-measures. This study aimed to determine the susceptibility of adult and larvae of Cx.quinquefasciatus mosquitoes (Diptera: Culicidae) to malathion; temephos; lambdacyhalothrin and permethrin insecticides in Khartoum locality.Material et methods:Susceptibility of Culex quinquefasciatus mosquitoes to malathion; lambdacyhalothrin and permethrin; and of the larvae to temephos in Khartoum locality was carried out; following WHO standard susceptibility tests. One to three days old female mosquitoes; which were reared from field collected immature stages; were exposed to discriminating dosages of the insecticides; for respective exposure periods. Then knockdown time and 24-hours mortality were recorded. For larvae which were exposed to a series of temephos concentrations; and LC 50 and LC 90 values were calculated.results:The study revealed that;Culex quinquefasciatus is predominant in Khartoum locality. Evidence of resistance was revealed to malathion and the two pyrethroids against Culex quinquefasciatus. The average KDT 50 values consider high and indicated resistance. But larvae stages were found to be susceptible to temephos.Interpretation et conclusion:Resistance of the field population of Cx. quinquefasciatus in Khartoum was revealed to malathion; lambdacyhalothrin and permethrin. On the other hand; the same population of Cx. quinquefasciatus is still sensitive to temephos. Therefore; the vector control unit should consider introducing rotation of insecticidesas a management strategy to increase the duration of the usage of the current insecticides. Furthermore; a rationalized use of insecticides coupled with regular monitoring of insecticide resistance is recommended to mitigate the rapid emergence of insecticide resistance