关键词: 中华按蚊, 实验室品系, 抗药性, 生物测定

Abstract:

Objective To determine the susceptibility of larvae and adults of a laboratory strain of Anopheles sinensis to the commonly used insecticides, and to provide a reference for comparison among field populations. Methods The insecticide resistance of An. sinensis laboratory strain was evaluated under laboratory condition with the WHO recommended bioassay on larvae and adults. Data were analyzed using Probit regression to determine LC₅₀ values. Results The mortality of An. sinensis adults exposed for 1 hour to the following insecticides was 56.5% to 4% DDT, 100% to 0.025% and 0.05% deltamethrin, 0.05% beta-cypermethrin, as well as 0.25% and 0.75% permethrin, while mortality to 0.025% beta-cypermethrin was slightly lower (99.6%). The susceptibility of An. sinensis larvae to deltamethrin, beta- cypermethrin, permethrin, temephos, spinosad, and dinotefuran as expressed by LC5(0 95%CI)was 0.0025(0.0021-0.0030), 0.0047(0.0035-0.0062), 0.0190(0.0156-0.0224), 0.1125(0.0921-0.1407), 0.0047(0.0035-0.0062), and 0.1744 (0.1653-0.1840)mg/L, respectively. Conclusion The laboratory strain of An. sinensis from National Institute for Communicable Disease Control and Prevention, Chinese Center for Disease Control and Prevention has showed reduced susceptibility to DDT, but remains susceptible to the commonly used pyrethroids as shown by bioassay data in adults. The actual resistance ratios in larvae and adults to the insecticides tested can be determined by comparing with known reference populations in the future if desired.

Key words: Anopheles sinensis, Laboratory strain, Insecticide resistance, Bioassay