海南省部分地区传疟媒介按蚊对4种常用杀虫剂的抗药性测定

目的了解海南省部分地区传疟媒介按蚊对4种常用杀虫剂的抗药性。方法于2008-2010年在多年使用杀虫剂防治疟疾的高疟区昌江县王下乡和东方市江边乡采集媒介按蚊,在昌江县王下乡以人诱法采集大劣按蚊,在东方市江边乡采用牛诱法采集中华按蚊和微小按蚊。取F0代中华按蚊雌蚊、F1代微小按蚊和大劣按蚊雌蚊为测试蚊虫,采用WHO成蚊滤纸接触筒法测定上述测试蚊虫接触4%DDT(1.428g/m2)、0.05%溴氰菊酯(0.0178g/m2)、0.15%氟氯氰菊酯(0.053 4 g/m2)和5%马拉硫磷(1.78 g/m2)等4种杀虫剂的区分剂量60 min内的击倒率,同时设空白对照组。计算半数击倒时间(KT50)和24 h后死亡率,以区分剂量判定抗性级别。结果 DDT、溴氰菊酯和马拉硫磷对大劣按蚊的死亡率均为100%;DDT和溴氰菊酯对大劣按蚊的击倒率分别为82.0%和100%,KT50值分别为46.9 min和18.4 min。DDT、溴氰菊酯、氟氯氰菊酯和马拉硫磷对微小按蚊的死亡率分别为98.1%、99.0%、100%和100%;DDT、溴氰菊酯、氟氯氰菊酯对微小按蚊的击倒率分别为96.3%、99.0%和100%,KT5...     

江苏省疟疾媒介中华按蚊对杀虫剂的敏感性

目的了解江苏省疟疾媒介中华按蚊对溴氰菊酯、DDT和马拉硫磷的敏感性。方法从泗洪、扬中、宜兴3县（市）现场捕获野外中华按蚊成蚊并培养子1代成蚊,采用WHO推荐的接触筒强迫接触法,观察计算中华按蚊接触杀虫剂10、15、20、30、40、50、60min的击倒率和24h后死亡率。结果泗洪、扬中、宜兴3县（市）野外中华按蚊子1代接触0.05%溴氰菊酯60min的击倒率分别为28.57%、57.14%和52.38%,24h后死亡率分别为35.71%、57.14%和61.90%,对溴氰菊酯抗性均达到R级;接触4%DDT60min的击倒率分别为9.52%、2.38%和4.76%,24h后死亡率分别为47.62%、50%和40.48%,对DDT的抗性均达到R级;接触5%马拉硫磷60min后击倒率分别为11.90%、28.57%和28.13%,24h后死亡率分别为80.95%、85.71%和93.75%,对马拉硫磷的抗性为M级。宜兴市野外中华按蚊捕获后1、7、15d及其子1代成蚊,接触0.05%溴氰菊酯60min的击倒率分别为54.76%、76.19%、92.86%和52.38%,24h后死亡率分别为54.76%、76.19%、95.23%和61.90%,捕获后1d与子1代成蚊24h后的死亡率差异无统计学意义（χ2=0.44,P〉0.05）。泗洪县中华按蚊子1代雌、雄成蚊接触0.05%溴氰菊酯60min的击倒率分别为28.57%和40.48%,24h后的死亡率为35.71%和42.86%,2种按蚊24h后的死亡率差异无统计学意义（χ2=0.45,P〉0.05）。结论江苏省野外中华按蚊已对溴氰菊酯、DDT产生高度抗性,对马拉硫磷已产生初步抗性。在媒介防制时应采取综合治理措施,以防止抗性进一步升高。     

湖北省部分地区中华按蚊对常用杀虫剂的抗药性监测

目的对中华按蚊的抗药性进行监测,为合理使用杀虫剂提供科学依据。方法采用成蚊滤纸接触法,按照WHO区分剂量,观察首只蚊虫击倒时间、击倒率和死亡率,以区分剂量判定抗性级别,以半数致死量确定抗性程度。结果监测点中华按蚊对DDT首只蚊虫击倒时间≥10 min,击倒率均20%,KT50176.86～1 718.63 min;溴氰菊酯和氟氯氰菊酯首只击倒时间为10～32 min和5～33 min,击倒率2.91%～18.35%和2.06%～15.00%;其中溴氰菊酯KT50138.41～6 234.72 min,比1996年调查的KT50提高了20～631倍。中华按蚊对DDT、溴氰菊酯和氟氯氰菊酯区分剂量死亡率均50%,对马拉硫磷区分剂量死亡率为10.20%～58.66%,其中DDT LC50均4%,与1993年的调查结果一致;溴氰菊酯LT50684.12 min,比1998年上升了306倍。结论中华按蚊对DDT抗性居高不下,对溴氰菊酯抗药性发展迅猛,可能成为疟疾媒介控制的最大障碍。区分剂量法是监测蚊虫对杀虫剂抗性的有效手段,击倒时间和击倒率的变化是检测早期击倒抗性(kdr)的敏感指标。     

2018—2020年贵州省中华按蚊抗药性调查研究

为了解目前贵州省中华按蚊对常见杀虫剂的抗药性水平,本研究选择贵州省从江县、播州区和荔波县为调查点,分别于2018、2019及2020年8月捕捉中华按蚊成蚊,根据WHO推荐使用的药膜接触筒法测定受试蚊对4%DDT、0.05%溴氰菊酯、5%马拉硫磷的敏感性,确定抗性级别,采用χ²检验比较60 min击倒率及校正死亡率的差异。从江、播州和荔波受试蚊均对0.05%溴氰菊酯首只击倒时间最长,分别为8.63、17.52、14.87 min,对4%DDT分别为6.33、2.95、11.88 min,对5%马拉硫磷分别为7.95、2.15、9.80 min。从江、播州和荔波受试蚊接触5%马拉硫磷药膜60 min后击倒率最高,分别为83.9%、39.0%、59.0%,3县(区)间差异有统计学意义(χ²=53.98,P<0.05);接触4%DDT药膜60 min后击倒率分别为61.9%、33.3%、36.2%,接触0.05%溴氰菊酯药膜分别为20.0%、34.2%、11.3%。从江、播州和荔波受试蚊接触4%DDT后的半数击倒时间(KT₅₀     

云南三带喙库蚊对DDT和溴氰菊酯的抗药性研究

目的了解云南省三带喙库蚊对DDT和拟除虫菊酯类的抗药性现状和分布。方法选择云南省昭通市昭阳区、德宏州芒市、普洱市江城县和孟连县,以及玉溪市元江县为调查点,采集三带喙库蚊成蚊,采用成蚊滤纸接触筒法,测定其对DDT和溴氰菊酯的敏感性,根据校正死亡率判定抗性级别。结果云南昭阳、芒市、江城、孟连和元江的三带喙库蚊暴露DDT 1 h,24 h后的死亡率分别为51.1%、86.8%、35.4%、21.0%和4.6%,KT50的范围为18.76~395.65 min,除芒市为初步抗性(M)外,其余4地均为抗性(R);对溴氰菊酯的死亡率分别为36.9%、59.2%、43.1%、34.1%和3.3%,KT50的范围为8.69~715.37 min,各调查点均为抗性(R)。结论云南省从北到南的三带喙库蚊对DDT和溴氰菊酯同时存在抗性,未来在上述地区使用化学杀虫剂的策略应进行调整。     

河南省部分地区中华按蚊对杀虫剂抗药性的监测

为了解传疟媒介中华按蚊对杀虫剂的抗药性状况,2021年7—9月于河南省信阳市平桥区、开封市祥符区、许昌市襄城县和南阳市唐河县等4县(区)的羊圈、猪圈或牛棚等附近采集按蚊,经形态学鉴定后,采用WHO推荐的成蚊滤纸接触筒法测定雌性中华按蚊对0.05%溴氰菊酯(0.017 8 g/m²)、0.15%高效氟氯氰菊酯(0.053 4 g/m²)、0.1%残杀威(0.035 7 g/m²)和5%马拉硫磷(1.78 g/m²)的抗药性,并判定中华按蚊对不同杀虫剂的抗性级别。结果显示,平桥区、祥符区、襄城县和唐河县共采集1 334只中华按蚊用于抗性测定。唐河县受试蚊接触溴氰菊酯的首只击倒时间最长为25.85 min,平桥区受试蚊接触高效氟氯氰菊酯药膜的首只击倒时间最短为2.83 min。平桥区、祥符区、襄城县和唐河县受试蚊接触高效氟氯氰菊酯的60 min后击倒率分别为24.42%(21/86)、2.47%(2/81)、37.31%(25/67)和45.45%(25/55)(χ²=39.355,...     

河南省濮阳市中华按蚊对杀虫剂敏感性调查

目的 了解河南省濮阳市中华按蚊对马拉硫磷、溴氰菊酯、高效氯氟氰菊酯的敏感性,为当地传疟媒介控制提供科学依据.方法 选择河南省濮阳市濮阳县为调查点,于2018年9月和2020年7月捕捉中华按蚊,采用滤纸接触筒法测定中华按蚊对马拉硫磷、溴氰菊酯、高效氯氟氰菊酯的敏感性,应用WHO抗药性评价标准确定抗性级别.结果 2018年...     

江苏省消除疟疾阶段媒介监测结果分析

目的 分析江苏省消除疟疾阶段媒介监测结果,为输入性疟疾在本地传播的风险评估和消除疟疾后监测提供科学依据。方法 2011-2017年每年6-10月,在江苏省媒介按蚊监测点采用半通宵人饵诱捕法、室外全通宵诱蚊灯法诱捕按蚊,进行按蚊种群和密度监测;采用WHO推荐的强迫接触筒法进行杀虫剂抗性监测。结果 2011-2017年,在江苏省7个媒介按蚊监测点采用半通宵人饵诱捕法共捕获中华按蚊5 106只,年均叮人率分别为1.075、0.786、1.057、0.787、0.790、1.797只/（人·h）和1.185只/（人·h）;采用室外全通宵诱蚊灯法共捕获中华按蚊28 186只,年均灯诱密度分别为57.950、50.932、14.800、4.405、58.070、72.406只/（灯·夜）和17.145只/（灯·夜）。2012年中华按蚊对溴氰菊酯、DDT和马拉硫磷的敏感性、抗性指数均为R级。结论 江苏省传疟媒介主要为中华按蚊,未发现嗜人按蚊;部分疟疾流行区中华按蚊已对溴氰菊酯、DDT和马拉硫磷产生高度抗性。     

安徽省中北部淡色库蚊对多种杀虫剂抗性及其kdr基因突变研究

目的 目的 了解安徽省中北部地区淡色库蚊对多种杀虫剂的抗药性现状及其kdr基因突变情况。方法 方法 2014年 6-9月在淮北市、 蚌埠市和滁州市3地采集淡色库蚊幼虫, 带回实验室饲养至成虫, 采用WHO成蚊接触筒药膜滤纸接触 法对其进行0.05%溴氰菊酯、 5%马拉硫磷、 0.1%噁虫威、 4%DDT抗性生物测定。以PCR扩增经溴氰菊酯抗性测定的库蚊 抗性相关kdr基因并进行测序, 统计L1014位点突变情况。结果 结果 上述3个地区淡色库蚊对溴氰菊酯、 马拉硫磷、 噁虫 威、 DDT 4种杀虫剂都产生了不同程度的抗药性, 对DDT产生的抗性较高; 虽然3地淡色库蚊接触DDT后的死亡率差异 无统计学意义 （F = 1.027,P > 0.05）; 但接触溴氰菊酯、 马拉硫磷、 噁虫威后的死亡率差异均有统计学意义 （F = 23.823、 33.955、 128.841, P均< 0.01）。3地淡色库蚊种群的kdr基因1014位点均存在L1014F、 L1014S 这2种非同义突变; L1014F 突变频率与溴氰菊酯抗性水平呈正相关 （r 2 = 0.718, P < 0.01）。结论 结论 安徽省中北部地区淡色库蚊对溴氰菊酯、 马拉硫 磷、 噁虫威、 DDT均产生了较强的抗性, kdr基因L1014F突变频率与溴氰菊酯抗性水平呈正相关; 各地区卫生部门需加强 对媒介蚊虫抗性的动态监测。     

成都市主要媒介蚊种对常用杀虫剂抗药性监测结果

本文报告了用区分剂量法、半数致死浓度法连续5年监测成都市主要媒介蚊种对化学杀虫剂（溴氰菊酯、氯菊酯、马拉硫磷、DDT）抗药性。致倦库蚊对所测杀虫剂均有明显抗药性；三带喙库蚊对马拉硫磷的抗药性明显，对溴氰菊酯和DDT存在初级抗性；中华按蚊对溴氰菊酯抗药性波动较大，但敏感性处于回升趋势，对马拉硫磷是相当敏感的，而对DDT有明显抗药性；嗜人按蚊对溴氰菊酯和DDT均敏感。     

河南省中华按蚊抗药性及其与kdr突变关联性的初步研究

目的 了解河南省主要传疟媒介中华按蚊对拟除虫菊酯类杀虫剂的抗药性及其与击倒抗性基因型的关联性.方法 2009年以区分剂量法调查河南省桐柏、淮滨和永城3地中华按蚊对溴氰菊酯和氟氯氰菊酯的抗药性,并抽取部分样本进行了kdr基因序列检测.χ2检验判断其抗药性与kdr基因突变的关联性.结果 河南省3县(市)中华按蚊溴氰菊酯和氟...     

不同剂型溴氰菊酯和氟氯氰菊酯对中华按蚊击倒力的试验

目的 比较不同剂型溴氰菊酯和氟氯氰菊酯浸泡蚊帐后的灭蚊效果。方法 采用击倒试验法和药帐接触法，观察中华按蚊的击倒和死亡情况。以Ｆｉｎｎｅｙ机率分析法进行统计分析，并进行显著性检验。结果 中华按蚊对不同剂型的溴氰菊酯和氟氯氰菊酯的ＫＴ５０在７．１７－１５．４５ｍｉｎ之间；被击倒蚊虫２４ｈ后的死亡率均为１００％；接触浸药帐ｍｉｎ的校正死亡均大于９０％；１年后中华按蚊的ＫＴ５０仍在１０．８２－１６．１７     

Multiple insecticide resistance/susceptibility status of Culex quinquefasciatus, principal vector of bancroftian filariasis from filaria endemic areas of northern India

ObjectiveTo understand the insecticide resistance status of Culex quinquefasciatus Say (Diptera: Culicidae) (Cx. Quinquefasciatus) to deltamethrin, cyfluthrin, permethrin, lambdacyhalothrin, DDT and malathion in filarial endemic areas of Uttar Pradesh, India.MethodsInsecticide susceptibility assays were performed on wild-caught adult female Cx. quinquefasciatus mosquitoes to deltamethrin (0.05%), cyfluthrin (0.15%), permethrin (0.75%), lambdacyhalothrin (0.05%), malathion (5.0%) and DDT (4.0%), the discriminating doses recommended by the World Health Organisation (WHO).ResultsThe data showed that Cx. quinquefasciatus is highly resistant to DDT and malathion; the mortality was 28.33% and 27.5%, respectively and incipient resistance to synthetic pyrethroids (deltamethrin, cyfluthrin, permethrin, and lambdacyhalothrin), where mortality ranged from 95.83% in permethrin to 98.33% in cyfluthrin and lambdacyhalothrin. Knockdown times (KDT₅₀) in response to synthetic pyrethroids varied significantly between different insecticides (P<0.01) from 31.480 min for permethrin to 21.650 for cyfluthrin.ConclusionsThe results presents here provide the status report of the insecticide resistance/susceptibility of Cx. quinquefasciatus in major filaria endemic areas of northern India.     

湖北省疟疾高发区媒介按蚊对杀虫剂敏感性的监测

目的 了解采取不同灭蚊措施后,嗜人按蚊和中华按蚊对溴氰菊酯和ＤＤ物敏感性。方法 采用ＷＨＯ成蚊滤纸接触法,观察蚊虫死亡率。结果 省氰菊酯浸帐灭蚊１年、３年和ＤＤＴ滞喷酒灭蚊３年的地区,嗜人按蚊对溴氰菊酯区分剂量死亡率分别为８３．８％,８３．７％和６４．７％,为初步抗性群体,ＬＴ６０分别为８．６９,７．４８和９．８７ｍｉｎ,中华按蚊对溴氰菊酯区分剂量死亡率分别为７６．５％,５７．０％和７９．０％,为     

Insecticide susceptibility of the dengue vector, Aedes aegypti (L.) in Metropolitan Bangkok

Mosquito larvae were collected from the houses of dengue infected patients in Bangkok, Thailand from 55 sites (36 out of the 50 districts of Metropolitan Bangkok). Aedes aegypti larvae were tested against temephos using WHO bioassay techniques. Adult mosquitoes were tested for susceptibility to permethrin, deltamethrin, cyfluthrin, malathion and DDT using WHO diagnostic doses. Most of the larvae tested were susceptible to temephos. Only few specimens were resistant to temephos. Most adult mosquitoes were highly susceptible to malathion. Deltamethrin resistance was seen in 6 districts of Bangkok. Variable levels of susceptibility were seen with cyfluthrin. Most of the specimens showed resistance to permethrin and all specimens were resistant to DDT.     

Irritability of malaria vector, Anopheles sacharovi to different insecticides in a malaria-prone area

ObjectiveTo determine the susceptibility and irritability level of malaria vector Anopheles sacharovi (An. sachrovi) to different insecticides in a malaria-prone area.MethodsSusceptibility and irritability levels of field collected strain of An. sacharovi to WHO standard papers of DDT 4%, dieldrin 0.4%, malathion 5%, fenitrothion 1%, permethrin 0.75%, and deltamethrin 0.05% were determined in East Azerbaijan of Iran during reemerging of malaria as described by WHO.ResultsResults showed that at the diagnostic dose of insecticides this species exhibited resistance to DDT, tolerant to dieldrin and but somehow susceptible to fenitrothion, malathion, permethrin and deltamethrin. The results of irritability of this species to DDT, lambdacyhalothrin, permethrin cyfluthrin and deltamethrin revealed that DDT had had the most and deltamethrin the least irritancy effect. The average number of take offs/fly/minutes for DDT was 0.8±0.2. The order of irritability for permethrin, lambdacyhalothrin, cyfluthrin and deltamethrin were 0.7±0.2, 0.5±0.2, 0.5±0.3, and 0.2±0.1, respectively.ConclusionsResults of this study reveals the responsiveness of the main malaria vector to different insecticides. This phenomenon is depending on several factors such as type and background of insecticide used previously, insecticide properties, and physiology of the species. Careful monitoring of insecticide resistance and irritability level of species could provide a clue for appropriate selection of insecticide for malaria control.     

Susceptibility of Anopheles gambiae s.l. to DDT, malathion, permethrin and deltamethrin in Ethiopia

Objective To assess the susceptibility/resistance level of Anopheles gambiae s.l. to DDT, malathion, permethrin and deltamethrin in different parts of Ethiopia. Methods Field collected female An.gambiae s.l. was exposed for 1 h to discriminating dosage of 4% DDT, 5% malathion, 0.75% permethrin and 0.05% deltamethrin using WHO insecticide susceptibility test kits and procedures. Knockdown and mortality rates were recorded at 10, 15, 20, 30, 40, 50 and 60 min and 24 h post‐exposure respectively. Results Anopheles gambiae s.l. was sensitive to DDT only in 2 of 16 localities where susceptibility studies were carried out in northern Ethiopia; it was resistant in 11 sites and potentially resistant in three. To malathion, the test population was sensitive in four of the six study sites in southern Ethiopia and potentially resistant in the other two sites. In northern Ethiopia, the population was resistant in five localities and sensitive in three. Of the six localities in northern Ethiopia where permethrin was tested, populations were sensitive in three, resistant in one and potentially resistant in two. In southern Ethiopia, the populations were resistant in five of the six sites. Against deltamethrin, the population was sensitive in five of 13 localities, three in northern and two in southern Ethiopia. It was resistant only in two localities, one in northern and one in southern Ethiopia, and potentially resistant in five localities. In eastern Ethiopia at Sabure, the population was sensitive to all insecticides but DDT to which it was potentially resistant. Conclusion The existence of high level of DDT and pyrethroid resistance with the possibility of cross‐resistance to each other and other classes of agricultural pesticides could seriously jeopardise the efficacy of both ITNs and IRS in the country in the future. Insecticide resistance monitoring and surveillance systems as part of a malaria control programme are mandatory for proper management of resistance. The use of a mixture of unrelated insecticides for impregnating nets and rotational use of insecticides for IRS is suggested as a way forward.