Campos J, Andrade C F
Departamento de Zoologia, Instituto de Biologia, Unicamp, Campinas, SP, Brasil.
Rev Saude Publica. 2001 Jun;35(3):232-6. doi: 10.1590/s0034-89102001000300003.
Insect susceptibility has been one of the most important aspects to be monitored in public health programs for vector control. The purpose of the study is to assess the susceptibility to chemical insecticides of Aedes aegypti larvae in both areas under vector control and no vector control.
World Health Organization standard bioassays for diagnostic concentration and multiple concentrations were performed in mosquito larvae collected in an area under no vector control (Campinas, SP) and an area under vector chemical control (Campo Grande, MS), in Brazil.
Potential resistance to a diagnostic concentration of temephos (DC=0.04 ppm) was registered for an Ae. aegypti larval population collected in Campinas. Multiple concentration tests confirmed the larvae resistance, with 24.5% of them surviving at the 0.0125 ppm concentration. Bioassays with the organophosphate fenitrothion (DC=0.08 ppm) and pyrethroid cypermethrin (DC=0.01 ppm) in the same population revealed their susceptibility to these agents. Bioassays carried out in an Ae. aegypti larval population collected in Campo Grande showed their susceptibility to temephos (DC=0.04 ppm) and cypermethrin (DC=0.01 ppm). LC50 and LC95 for cypermethrin (CE25), cyfluthrin (CE5), betacyfluthrin (SC1.25) and propoxur (CE20) were determined for Ae. aegypti. Using the Rockefeller standard strain values, ratios of resistance were estimated: 2.9, 2.2, 2.4 and 1.3 for LC50 and 3.5, 2.6, 3.9 and 1.3 for LC95, respectively.
The findings reinforce the need for routinely monitoring pesticide efficacy as a very important step in vector control management programs.
在公共卫生病媒控制项目中，昆虫易感性一直是需要监测的最重要方面之一。本研究的目的是评估在病媒控制区和非病媒控制区埃及伊蚊幼虫对化学杀虫剂的易感性。
在巴西未进行病媒控制的地区（圣保罗州坎皮纳斯）和进行化学病媒控制的地区（南马托格罗索州大坎普）采集的蚊虫幼虫中，进行了世界卫生组织诊断浓度和多浓度标准生物测定。
在坎皮纳斯采集的埃及伊蚊幼虫群体中，记录到对诊断浓度的毒死蜱（DC = 0.04 ppm）有潜在抗性。多浓度测试证实了幼虫的抗性，其中24.5% 的幼虫在0.0125 ppm浓度下存活。对同一群体进行的有机磷杀螟硫磷（DC = 0.08 ppm）和拟除虫菊酯氯氰菊酯（DC = 0.01 ppm）生物测定显示它们对这些药剂敏感。在大坎普采集的埃及伊蚊幼虫群体中进行的生物测定显示它们对毒死蜱（DC = 0.04 ppm）和氯氰菊酯（DC = 0.01 ppm）敏感。测定了埃及伊蚊对氯氰菊酯（CE25）、氟氯氰菊酯（CE5）、高效氟氯氰菊酯（SC1.25）和残杀威（CE20）的LC50和LC95。使用洛克菲勒标准品系的值，估计抗性比率：LC50分别为2.9、2.2、2.4和1.3，LC95分别为3.5、2.6、3.9和1.3。
研究结果强化了在病媒控制管理项目中，将定期监测农药效果作为非常重要一步的必要性。
