Fonseca-González Idalyd, Cárdenas Rocío, Quiñones Martha L, McAllister Janet, Brogdon William G
Grupo Biología y Control de Enfermedades Infecciosas, Instituto de Biología, Universidad de Antioquia, Medellín, Colombia.
Parasitol Res. 2009 Oct;105(5):1399-409. doi: 10.1007/s00436-009-1570-2. Epub 2009 Aug 5.
Field populations of Colombian malaria vector Anopheles (N.) nuneztovari were studied using World Health Organization (WHO) and Center for Disease Control and Prevention (CDC) bioassay techniques and through the use of biochemical microplate-based assays for resistance enzymes. Insecticides evaluated included the pyrethroids lambda-cyhalothrin and deltamethrin, organophosphates malathion and fenitrothion, and the organochlorine dichlorodiphenyltrichloroethane (DDT). Study sites selected were based upon malaria incidence, vector presence, and control activities in Colombia. Early stage selection for reduced susceptibility was observed in the bioassays for some locations. Data from the WHO and CDC bioassay methods were broadly consistent, with some differences noted. Evidence is presented for low-level initial selection of some resistance mechanisms such as mixed-function oxidases and modified acetylcholinesterase. Data from the site Encharcazón implies that selection for DDT-pyrethroid cross-resistance has occurred, though not likely at a level that currently threatens vector control by either class of insecticides, and further implies that knockdown resistance (kdr) may be present in those populations. Further studies using synergists and development of a kdr-specific assay for A. nuneztovari thus become priorities. The resistance levels to lambda-cyhalothrin and deltamethrin found in the Encharcazón population are of concern since these two insecticides are currently used for both indoor spraying and treated nets. In addition, the resistance to fenitrothion, the indoor spray insecticide mostly used for this species due to their exophilic behavior, found in the El Zulia population, makes urgent to find alternatives for chemical control in these areas. These data provide the initial baselines for insecticide susceptibility profiles for A. nuneztovari in Colombia and the first report of insecticide resistance in this vector.
利用世界卫生组织（WHO）和疾病控制与预防中心（CDC）的生物测定技术，并通过基于生化微孔板的抗性酶检测方法，对哥伦比亚疟疾传播媒介努内斯按蚊（N.)的野外种群进行了研究。评估的杀虫剂包括拟除虫菊酯高效氯氟氰菊酯和溴氰菊酯、有机磷马拉硫磷和杀螟硫磷，以及有机氯二氯二苯三氯乙烷（DDT）。所选研究地点是基于哥伦比亚的疟疾发病率、媒介存在情况和防治活动确定的。在某些地点的生物测定中观察到了对杀虫剂敏感性降低的早期选择。WHO和CDC生物测定方法的数据大致一致，但也存在一些差异。有证据表明，对某些抗性机制如多功能氧化酶和修饰乙酰胆碱酯酶存在低水平的初始选择。来自恩查尔卡松地点的数据表明，已经出现了对滴滴涕 - 拟除虫菊酯交叉抗性的选择，尽管目前这两类杀虫剂对媒介控制的威胁程度可能不高，并且进一步表明这些种群中可能存在击倒抗性（kdr）。因此，使用增效剂进行进一步研究以及开发针对努内斯按蚊的kdr特异性检测方法成为当务之急。恩查尔卡松种群中对高效氯氟氰菊酯和溴氰菊酯的抗性水平令人担忧，因为这两种杀虫剂目前用于室内喷洒和经处理蚊帐。此外，在苏利亚地区发现的对杀螟硫磷（由于其嗜外行为而大多用于该物种的室内喷洒杀虫剂）的抗性，使得迫切需要在这些地区寻找化学防治的替代方法。这些数据为哥伦比亚努内斯按蚊的杀虫剂敏感性概况提供了初步基线，也是该媒介中杀虫剂抗性的首次报告。
