关键词: 疟疾, 按蚊, 抗药性

Abstract: Objective To understand the resistance of Anopheles to DDT and Deltamethrin,and then provide scientific evidence for the establishment of prevention and control strategy.Methods Adult Anopheles filter contact method recommended by WHO was used to observe the knockdown rate and the mortality of Anopheles,and the relationship of logarithm-probability was analyzed with the method of Finney probability.Results The Anopheles had high resistance to DDT and deltamethrin in Jingshan county,Anlu city and Xiaochang county,and the knockdown rates of DDT and deltamethrin discrimination dosage to it were less than 20%,and their mortality were all less than 50%.The KT₅₀ values of DDT were 1718.63,343.73 and 624.45 min respectively,which had higher anti-knockdown capability.The LC₅₀ of DDT exceeded 4%,accordant with that in 1996.The KT₅₀ of deltamethrin were 227.78,138.41 and 263.41 min respectively,which were 34,20,44 times than that in 1996,respectively.The LT₅₀ was 684.12 min,which was 306 times than that in 1998.Conclusion The resistance did not decrease after the forbiddance of DDT for many years,however,the resistance to deltamethrin increases at the several hundred times speed,which could be the obstacle of pyrethroid and DDT application,so we should carry out regular monitoring and make effective measures timely.