上海市金山区白纹伊蚊对常用杀虫剂的抗药性调查

目的 了解上海市金山区白纹伊蚊对常用杀虫剂的抗药性水平,为规范用药提供参考依据。方法 采用幼虫浸渍法检测白纹伊蚊幼虫对5种杀虫剂的抗药性,使用SPSS 18.0软件计算毒力回归方程及杀虫剂对幼蚊半数致死浓度（LC50）;用成蚊接触筒法检测白纹伊蚊成蚊在常用杀虫剂诊断剂量时24 h死亡率,评价抗药性水平。结果 2018和2019年上海市金山区白纹伊蚊幼虫对高效氯氰菊酯呈现中度和高度抗药性,抗性倍数分别为25.03和65.96倍;对溴氰菊酯呈现高度抗药性,抗性倍数分别为57.25和211.75倍;对氯菊酯呈现高度抗药性,抗性倍数为46.17和243.36倍;2018—2019、2021和2023年对双硫磷呈现中度和高度抗药性,抗性倍数分别为19.55、23.94、53.48和22.12倍;2021和2023年对倍硫磷呈现中度抗药性,抗性倍数分别为30.04和12.54倍。2021和2023年上海市金山区白纹伊蚊成蚊对0.03%溴氰菊酯、0.07%高效氯氟氰菊酯、0.4%氯菊酯和0.08%高效氯氰菊酯均呈现抗性,死亡率在17.20%～49.67%;对0.7%高效氯氟氰菊酯和0.2%杀螟硫磷均...     

广西部分浸帐区疟疾按蚊媒介对菊酯杀虫剂的敏感度

目的：了解广西部分浸帐区疟疾按蚊媒介对菊酯杀虫剂的敏感度。方法：采用成蚊药帐接触法，分别用除敌、奋斗呐、杀飞克及拜虫杀，按20mg a.i/m^2的剂量来浸泡蚊帐纱布，野外吸血按蚊暴露于药帐3min，观察24h死亡率。结果：环江县及那坡县浸帐区及对照区的按蚊触药为24h死亡率均大于90％，并且浸帐区与非浸帐区死亡率无差异。结论：广西环江县及那坡县应用拟除虫菊酯杀虫剂浸泡蚊帐后当地按蚊对4种常用拟除菊酯杀虫剂仍敏感；选择性局部应用菊酯杀虫剂可以延缓环江县及那坡县野外按蚊对菊酯杀虫剂产生抗药性；成蚊药帐接触法是一种实用的现场快速检测按蚊敏感度/抗药性的方法。     

海口市致倦库蚊成蚊对3种菊酯类杀虫剂的抗性调查

目的 了解海口市致倦库蚊成蚊对高效氯氰菊酯、氯菊酯、溴氰菊酯等3种菊酯类杀虫剂的抗药性水平,为合理使用杀虫剂提供科学依据。方法 在海口市演丰镇、新埠岛、长流镇、苍西村、龙泉镇5个地点采集致倦库蚊幼虫,实验室饲养至成蚊,采用成蚊接触筒法,测定海口市致倦库蚊成蚊对3种菊酯类杀虫剂的抗药性。结果 5个采集点的致倦库蚊成蚊对0.025%高效氯氰菊酯、0.25%氯菊酯、0.025%溴氰菊酯24 h 死亡率分别为16.67%~92.22%、5.56%~93.33%、15.56%~94.44%;海口市致倦库蚊成蚊对3种菊酯类杀虫剂的死亡率由低到高分别为溴氰菊酯（51.56%）、氯菊酯（56.22%）、高效氯氰菊酯（59.56%）,死亡率均在80%以下。结论 海口市致倦库蚊成蚊对3种菊酯类杀虫剂产生了抗性,在今后的蚊虫防制中,应科学合理使用杀虫剂,延缓抗药性的产生。     

青浦区蚊蝇、蟑螂对3种杀虫剂的抗药性监测分析

目的了解青浦区蚊、蝇、蟑螂对敌敌畏等3种常用杀虫剂的抗药性,以便通过抗药性水平来科学、合理的使用杀虫剂。方法采用浸液法,测定Ⅲ末龄期幼虫半数致死浓度;点滴法,测定家蝇半数致死量;采用500ml广口瓶药膜接触法,测定德国小蠊半数击倒时间。结果蚊、蝇、蟑螂对敌敌畏等3种杀虫剂产生不同程度抗药性,即淡色库蚊对敌敌畏抗药性级别为高抗,氯氰菊酯、溴氰菊酯为抵抗;家蝇对敌敌畏、氯氰菊酯、溴氰菊酯抗药性级别均为高抗;蟑螂对氯菊酯、氯氰菊酯、敌敌畏抗药性级别均为敏感。结论在蚊、蝇、蟑螂的防治过程中,根据其抗药性情况,必须选择适当的杀虫剂。     

湖北省部分县市媒介按蚊对杀虫剂抗药性监测与分析

目的了解媒介按蚊对杀虫剂抗性程度,为合理使用杀虫剂提供科学依据。方法 2007年和2012年对湖北省江陵等部分县市媒介按蚊的抗药性进行了监测,采用WHO成蚊滤纸接触法,以区分剂量死亡率判定抗性级别,以开始击倒时间和击倒率评估Kdr抗性,以半数致死量确定抗性水平。结果 9个监测点媒介按蚊首只蚊虫被击倒的时间为5~30 min,击倒率为1.00%~48.94%,表明其抗击倒力较强。区分剂量校正死亡率均小于80%,为抗性群体。京山县、安陆市、孝昌县和仙桃市媒介按蚊对溴氰菊酯KT50分别为227.78、138.41、263.41和6 234.72 min,比1996年提高了20~631倍。京山县媒介按蚊对0.05%溴氰菊酯LT50为684.12 min,比1998年提高了306倍。结论媒介按蚊对溴氰菊酯均已产生抗性,且抗击倒力较强,抗性程度较高,应加强监测。     

电压门控钠离子通道基因I1532T突变与白纹伊蚊对菊酯类杀虫剂敏感性的相关性

目的 探讨I1532T突变与白纹伊蚊对氯菊酯和溴氰菊酯杀虫剂抗药性的相关性。方法 利用实验室饲养的白纹伊蚊长宁株作为试虫,分别对幼虫和成虫阶段,以幼虫浸渍法和成虫接触筒法对溴氰菊酯和氯菊酯的敏感性进行生物测定。收集生物测定死亡和存活的个体单只抽提基因组DNA,PCR扩增电压门控钠离子通道（voltage-gated sodium channel, VGSC）基因部分片段,测序并检测击倒抗性（knockdown resistance, kdr）突变情况,χ²检验I1532T与2种菊酯类杀虫剂抗药性的相关性。结果 幼虫浸渍法的结果显示,白纹伊蚊长宁株对氯菊酯和溴氰菊酯的LC₅₀分别是敏感品系的2.23倍和3.31倍,提示对2种杀虫剂均为敏感。成蚊接触筒测定的结果显示,接触氯菊酯和溴氰菊酯后成蚊的死亡率分别为74.69%和78.79%,提示白纹伊蚊长宁株对氯菊酯和溴氰菊酯均已产生抗性。本研究共测定了401只白纹伊蚊长宁株的VGSC基因部分片段,1532位点为突变基因型（突变纯合子ACC/ACC和野生突变杂合子ATC/ACC）的占59.10%,其余为野生型ATC/ATC,占40.90%;1534位点为突变基因型（突变纯合子TCC/TCC和野生突变杂合子TTC/TCC）的占4.49%,其余为野生型TTC/TTC,占95.51%。结果显示,白纹伊蚊幼虫氯菊酯或溴氰菊酯抗药性表型与敏感表型之间的I1532T突变频率差异均无统计学意义（P>0.05）;成虫的氯菊酯抗药性表型与敏感表型之间的I1532T等位基因型频率差异（P=0.019）和基因型频率差异（P=0.044）有统计学意义,而溴氰菊酯抗药性表型与敏感表型的I1532T等位基因型和基因型频率差异无统计学意义（P>0.05）。结论 VGSC基因I1532T突变使白纹伊蚊成虫对氯菊酯敏感性下降,但与溴氰菊酯敏感性无相关性。     

爱克宁微胶囊剂对大劣按蚊毒效的试验观察

为了考核爱克宁微胶囊剂浸泡蚊帐对海南传疟媒介大劣按蚊的毒力大小．我们在实验室进行了药效测定。现将结果报告如下。1．材料与方法1．1试验材料1．1．1试验药物：爱克宁（ICON）10％微胶囊剂，由捷利康中国有限公司提供。澳佩菊酯（Deltamethrin）2．5％乳油．由海南力力达农药厂提供。1．1．2试虫；大劣按蚊（AnophelesDirus）为本所养蚊室饲养的未吸血羽化3～5日龄雌成蚊。1．2试验方法将杀虫剂按一定倍数稀释后．浸泡用棉蚊帐有制成的蚊笼，凉干后进行试验。爱克宁浸泡两个蚊笼，有效成份分别为：15mg／m2、20mg／m2。为了便于比较…     

安康市淡色库蚊对常用杀虫剂的抗性状况及防制对策的研究

目的掌握安康市淡色库蚊对常用杀虫剂的抗性现状,研究防制对策。方法采用区分剂量法测定淡色库蚊幼虫对4种杀虫剂的24h死亡率;采用半数致死浓度(LC50)法测定淡色库蚊幼虫对8种杀虫剂的LC50。结果依据区分剂量抗性评价标准,安康市淡色库蚊对DDT、敌敌畏、氯菊酯、溴氰菊酯均属抗性群体。LC50测定结果显示,安康市淡色库蚊对DDT、敌敌畏、氯菊酯、氯氰菊酯、高效氯氰菊酯、溴氰菊酯、双硫磷、残杀威的LC50分别为0.58110、0.40 039、0.02 345、0.01 088、0.0 049、0.00 559、0.00 277、0.23 460mg/L,与实验室敏感试虫比较,安康市淡色库蚊各药物的抗药性均高过敏感试虫,抗性在2.49～14.33倍之间,其中以溴氰菊酯相差最大(14.33倍)。抗性等级溴氰菊酯为中抗,其余药物为低抗。结论蚊虫抗药性的产生与长期、大量、乱用杀虫剂密切相关,在蚊虫防制中要定期开展抗药性监测,科学合理用药,提倡综合防制,以减缓蚊虫抗药性的产生。     

漯河市淡色库蚊对5种常用杀虫剂的抗药性调查

目的了解漯河市淡色库蚊对双硫磷、仲丁威、溴氰菊酯、氯氰菊酯及高效氯氰菊酯5种杀虫剂的抗药性现状,为制订防制对策提供科学依据。方法采用药液浸渍法,测定淡色库蚊4龄期幼虫的半数致死浓度(LC50)。结果淡色库蚊对双硫磷和仲丁威的抗性较低,抗性指数分别为2.24、1.33;对氯氰菊酯和溴氰菊酯抗性较高,抗性指数分别为15.92、23.16。结论淡色库蚊对5种杀虫剂均产生了不同程度的抗药性,但以溴氰菊酯和氯氰菊酯为高。     

海南省病媒蚊虫抗药性监测报告

本文报告采用区分剂量法对城市主要病媒蚊虫抗药性监测．结果表明，致倦库蚊对5种杀虫剂抗性率为97．7％，其中高抗为60．5％，实际抗性25．6％，初级抗性11．6％。埃及伊蚊，白纹伊蚊对DDT、溴氰菊酯、氯菊酯也产生抗药性。溴氰菊酯比氯菊酯发生抗性快和高。作者认为：DDT与拟除虫菊酯有交互抗性，不宜同时使用或轮用，出现高抗地区应换用有机磷杀虫剂，以防止抗击倒基因聚集。     

DELTAMETHRIN IMPREGNATED MOSQUITO NETS : AN EXPERIMENTAL STUDY IN AN AIR FORCE STATION IN CENTRAL INDIA (DELTAMETHRIN TRIAL)

An experimental study was carried out to determine the efficacy of deltamethrin impregnated mosquito nets in reducing malaria incidence under field conditions in an Air Force Station. Out of the total study population of 748 airmen and DSC personnel, 320 got their mosquito nets impregnated with deltamethrin, while 428 used unimpregnated mosquito nets. During the three months observation period, there was no significant difference in malaria incidence among the two groups (Yates Chi Sq=0.05, p=0.829405, Relative risk = 0.96 with 95% CI between 031 and 2.98). In view of study findings, it was concluded that in the station, use of deltamethrin impregnated mosquito nets will not reduce incidence of malaria appreciably, the stress has to be on outdoor personal protective measures.KEY WORDS: Deltamethrin, Malaria, Synthetic pyrethroids     

海口市按蚊调查和疟疾再传播风险评估

目的 了解海口市当前的按蚊的种类、分布及季节消长情况,为评估疟疾再传播风险提供科学依据。方法 采用灯光诱捕法（诱蚊灯法）、动物诱捕法（动物帐诱法）、人诱捕法（人诱停落法）,从海口市4个区中随机抽取13个乡镇所辖自然村进行按蚊种类及分布调查;并选取1个自然村为固定监测点,研究媒介按蚊季节消长规律。结果 在13个调查点共捕获按蚊9种1 684只。棋斑按蚊占61.82%,中华按蚊占34.80%,迷走按蚊占2.61%,乌头按蚊均占0.24%,须喙按蚊占0.18%,美彩按蚊占0.12%,带足按蚊占0.12%,嗜人按蚊占0.06%,多斑按蚊占0.06%;在固定监测点1~12月共捕获按蚊7种1 421只。其中中华按蚊、棋斑按蚊、迷走按蚊所占比例分别为44.76%、39.55%、15.20%。按蚊数量从4月份开始增多,9月达到高峰,4—11月捕获数占全年93.31%;中华按蚊全年都有活动。结论 海口市当前主要按蚊种类为棋斑按蚊、中华按蚊。中华按蚊分布广、密度高,全年均有活动;嗜人按蚊仅在局部地区发现,且密度较低,未发现历史上主要的传疟媒介微小按蚊。海口市属于高再传播风险地区。     

四川省自贡市主要媒介蚊虫密度及其对杀虫剂抗药性监测

目的 了解自贡市媒介蚊虫的种群构成、密度及季节变化规律,并对自贡市致倦库蚊和白纹伊蚊对常见杀虫剂的抗药性测定,为科学选择和使用杀虫剂,防控蚊媒传染病提供科学依据。方法 在全市范围内采集致倦库蚊和白纹伊蚊,经实验室饲养后,采用成蚊接触筒法分别测定试虫对几种常用杀虫剂的抗药性,利用Excel 2010软件对2018—2020年自贡市媒介蚊虫监测数据进行统计分析。结果 2018—2020年自贡市监测点年均蚊密度分别为1.11、10.71、4.81只/（灯·h）,2018—2020年自贡市全年蚊密度季节消长趋势均呈现单峰型,7月最高,不同生境间蚊密度差异明显,牲畜棚蚊密度最高。白纹伊蚊和致倦库蚊对高效氯氰菊酯、高效氯氟氰菊酯、溴氰菊酯、氯菊酯、马拉硫磷、杀螟硫磷、毒死蜱、残杀威、噁虫威24 h致死率分别为70.71%和3.85%、26.53%和1.68%、19.79%和1.94%、40.80%和0.81%、97.98%和3.85%、100.00%和7.52%、100.00%和66.34%、96.15%和33.60%、100.00%和71.43%。白纹伊蚊对高效氯氰菊酯、高效氯氟氰菊酯、溴氰菊酯、氯菊酯产生抗药性,对马拉硫磷、残杀威产生可疑抗性,对毒死蜱、杀螟硫磷、噁虫威敏感;致倦库蚊对所有杀虫剂均产生不同程度的抗药性。结论 白纹伊蚊、致倦库蚊对拟除虫菊酯类杀虫剂均产生较高抗药性。应加强爱国卫生运动,减少拟除虫菊酯类杀虫剂的使用,轮换使用不同类型的杀虫剂,以延缓抗药性的产生,提高蚊密度控制效果。     

江苏省不同地区中华按蚊季节消长与夜间活动规律比较

目的了解江苏省不同地区中华按蚊季节消长与夜间活动规律,为消除疟疾提供科学依据。方法2011年,选择江苏省13个直辖市各1个乡（镇）作为疟疾媒介监测点,采用通宵室外帐内人饵诱捕法,观察各监测点中华按蚊的季节消长和夜间活动规律。并按照监测点的地理位置,划分为苏南、苏中、苏北并对数据进行统计分析。结果 2011年,江苏省13个疟疾媒介监测点共捕获2044只按蚊,经鉴定全部为中华按蚊,未发现嗜人按蚊。江苏省中华按蚊季节消长密度高峰为7月下半月,对苏北地区、苏中地区和苏南地区的中华按蚊数量进行统计学分析,差异无统计学意义（F=1.769,P=0.19）。江苏省中华按蚊夜间活动高峰出现在19：00至22：00间的3h,共捕获中华按蚊1388只,占全部12个时间段所捕获中华按蚊数的的67.91%;中华按蚊在清晨时分又出现一个小高峰,5：00至6：00时间段共捕获中华按蚊184只,占全部12个时间段的9.00%。对苏北地区、苏中地区和苏南地区的中华按蚊数量进行统计学分析,差异有统计学意义（F=291.88,P=0.000）。结论应做好傍晚和清晨的个人防护措施,避免蚊虫叮咬,降低疟疾的传播机会。仍应继续加强媒介的监测与控制,为消除疟疾起到以点带面的作用。     

Study of the Impact of Deltamethrin Impregnated Mosquito Nets on Malaria Incidence at a Military Station

Deltamethrin impregnated mosquito nets have been successfully used all over the world to combat malaria. To study the efficacy of these mosquito nets in the service conditions of Armed Forces, a field trial of Deltamethrin impregnated mosquito nets was carried out at Military Stations ‘A’ (trial station) and B (control station) between July 96 to June 99. July 96-June 97 was the pretrial year during which base line data was collected for malaria incidence. Three rounds of Deltamethrin impregnation of the mosquito nets were done in the trial station for the actual trial duration (July 97-June 99) in lieu of residual spraying. Antimalaria measures including residual spray were continued as usual in the control station. The intervention led to a significant decline in slide positivity rate and malaria incidence in the trial station. Malaria cases declined by 87% in the trial station whereas the control station noticed an increase by 75% at the end of the trial.Key Words: Deltamethrin impregnated mosquito nets, Malaria control     

Evidence of increasing L1014F kdr mutation frequency in Anopheles gambiae s.l. pyrethroid resistant following a nationwide distribution of LLINs by the Beninese National Malaria Control Programme

Objective

To determine the susceptibility status to pyrethroid in Anopheles gambiae s.l. (An. gambiae), the distribution of kdr “Leu-Phe” mutation in malaria vectors in Benin and to compare the current frequency of kdr “Leu-Phe” mutation to the previous frequency after long-lasting insecticide treated nets implementation.

Methods

Larvae and pupae of An. gambiae s.l. mosquitoes were collected from the breeding sites in Littoral, Zou, Borgou and Alibori provinces. CDC susceptibility tests were conducted on unfed females mosquitoes aged 2-5 d old. An. gambiae mosquitoes were identified to species using PCR techniques. Molecular assays were also carried out to identify kdr mutations in individual mosquitoes.

Results

The results showed that An. gambiae Malanville and Suru-lere populations were resistant to deltamethrin. Regarding An. gambiae Parakou and Bohicon populations, they were resistant to permethrin. PCR revealed 100% of mosquitoes tested were An. gambiae s.s. The L1014F kdr mutation was found in An. gambiae s.s. Malanville and Parakou at various allelic frequencies. The increase of kdr allelic frequency was positively correlated with CDC bioassays data.

Conclusions

: Pyrethroid resistance is widespread in malaria vector in Benin and kdr mutation is the main resistance mechanism involved. More attention may be paid for the future success of malaria control programmes based on LLINs with pyrethroids in the country.     

溴氰菊酯选育淡色库蚊和中华按蚊的研究

淡色库蚊经溴氰菊酯选育１０代，Ｌｅ５０由０．０４０２ｐｐｍ上升至２１．２７３８ｐｐｍ，抗性高达５２９．２０倍，抗性呈指数曲线上升；中华按蚊被处理８代，Ｌｅ５０由０．０２５６ｐｐｍ至第４代（Ｆ３）时的０．０４８ｐｐｍ，抗性指数为１．８８，其后逐比下降至处理起点水平上波动。溴氰菊酯与增效醚混用后，毒效明显增加，表明多功能氧化酶活力增强是拟除虫菊酯类抗性机理之一。     

部队营区用奋斗呐浸泡蚊帐防治蚊虫的效果观察

本文报告了1990年在广东省台山农场上川岛、罗浮山和深圳平湖部队营区,用顺式氯氰菊酯25mg,ai/m~2浸泡蚊帐灭蚊防疟效果。在台山农场浸帐后4个月,蚊虫密度下降率仍达97.7%。在深圳平湖,浸帐后4个月内无一疟疾病例发生。结果说明奋斗呐浸泡蚊帐县有较长时间的灭蚊效果和防疟作用。     

Monitoring of malaria,Japanese encephalitis and filariasis vectors

Background

Vector monitoring in military stations would help in protecting the armed forces from vector borne diseases such as malaria, Japanese encephalitis and filariasis.

Methods

Adult mosquitoes were collected from four villages around a military station in India using light traps and the species composition was estimated. Insecticide susceptibility of disease vectors against DDT, deltamethrin and permethrin was established using WHO kits.

Results

The known malaria vectors constituted 4.9% of the total mosquito collections and Anopheles philippinensis/nivipes (2.05%) was the most abundant. Japanese encephalitis and dengue vectors constituted 25.3 and 0.05% whereas the known vectors of both Japanese encephalitis and filariasis formed 50.9%. The mean (±SE_mean) of annual parasitic index, slide positivity and Plasmodium falciparum percentage among the civilian population during the study period were 1.46 ± 0.37, 1.65 ± 0.77 and 50.2 ± 10.7. The filariasis vector Culex quinquefasciatus was resistant to DDT with 65.4% mortality whereas the DDT resistance in the Japanese encephalitis vector Culex vishnui gr. with 91.9% mortality needs to be confirmed. All other species tested were susceptible to DDT, deltamethrin and permethrin.

Conclusion

Targeted interventions are needed to reduce the disease burden and vector activity in the villages adjoining the military station. The use of insect repellents, bed nets and repellent impregnated uniforms by the troops should be ensured for protection from vector borne diseases.