宁波市蚊类种群1999～2002年的年际动态变化

目的　通过调查不同年份蚊虫种群的密度 ,以了解宁波地区蚊虫种群的年际变化规律 ,从而为蚊虫种群的有效控制提供理论依据。方法　采取定点定时的方法 ,利用直流电动捕蚊器捕捉蚊虫 ,然后分种统计捕获的蚊虫数。结果　宁波地区的优势蚊种为中华按蚊、淡色库蚊和三带喙库蚊 ,其中中华按蚊占捕获蚊虫总数的 42 .0 1%。 1999～ 2 0 0 2年蚊类种群密度波动较大 ,其中波动幅度最大的是淡色库蚊。 3种优势蚊种的季节分布呈单峰型 ,总体上最高峰在 6～ 8月 ,其中中华按蚊的高峰期出现在 4～ 5月 ,淡色库蚊的高峰期出现在 7～ 8月 ,三带喙库蚊则出现在 9～ 10月。结论　根据蚊虫种群密度的年际变化和季节消长规律 ,宁波地区蚊虫种群的控制工作重点是在每年的 4～ 5月 ,消灭各类孳生地中的蚊幼 ,以降低全年的蚊虫种群密度     

2022年四川省传疟媒介监测结果分析

目的 分析四川省监测县传疟媒介种群分布、密度及季节消长情况,为消除疟疾后疫点处置提供参考。方法 2022年5至9月随机选取了73个传疟媒介种群调查监测县和23个种群和密度调查监测县分别通过灯诱法和人帐诱法开展种群和密度监测,对捕获到的蚊虫进行形态学鉴定,对捕获蚊虫、按蚊数量、密度利用WPS Office软件建立数据库,用SPSS26.0软件进行方差分析和卡方检验等描述性统计分析,检验水准为α=0.05。结果 2022年在5至9月期间有165个点开展种群监测,23个点开展了密度监测。共捕获180 402只蚊虫,其中按蚊有26 521只(14.70%)。中华按蚊26 274只(99.07%),嗜人按蚊19只(0.07%),未鉴定按蚊种70只(0.26%),未捕获到微小按蚊和大劣按蚊。通过灯诱法捕获到民房外3 712只中华按蚊(15.45%),牲畜房14 390只(59.88%),可孳生地5 927只(24.67%);仅青神县和洪雅县捕获到18只嗜人按蚊;未鉴定的按蚊位于资中县;不同场所中华按蚊和嗜人按蚊构成差异有统计学意义(χ²=29.33,P<0.001)。有...     

浙江口岸蚊类及病原体携带情况调查与分析

目的对浙江口岸蚊类的种群结构、密度和季节消长情况,以及主要蚊媒病原体携带情况进行调查分析,为制定有效的防制措施和控制口岸蚊媒传染病的发生提供科学依据。方法采用诱蚊器收集法捕捉浙江口岸的蚊虫,对其进行形态学分类鉴定;采用荧光定量RT-PCR法对蚊类样品进行登革热病毒、流行性乙型脑炎（乙脑）病毒、西尼罗病毒及疟原虫等病原体检测。结果浙江口岸蚊类隶属5属12种,其中淡色/致倦库蚊为优势种,占捕获总数的57.87%,其次是中华按蚊,占23.75%;平均密度0.38只/（台·h）,活动高峰期为6-8月;蚊类可能携带的登革热病毒、乙脑病毒、西尼罗病毒及疟原虫等病原体检测结果全部为阴性。结论浙江口岸主要优势种与地方数据基本一致,但各口岸又有不同特点;输入性疟疾在浙江口岸地区有暴发流行的可能;浙江口岸蚊类受登革热病毒等病原体感染的可能性较低;台州、嵊泗口岸蚊密度偏低,可能与台州口岸特殊的港区环境、嵊泗口岸当地特有的海岛型气候相关;空港蚊密度明显高于海港,可能与其特有的蚊类生活环境和人员较多有关。     

嗜人按蚊和中华按蚊相关细菌差异的初步探讨

目的通过对河南省桐柏地区嗜人按蚊和中华按蚊的DNA提取物中细菌DNA的拷贝数和种类是否存在差异进行初步探讨，为进一步深入开展蚊媒中肠细菌与蚊媒传播疟疾能力之间的关系提供理论基础。方法以保存于75％乙醇中的成蚊为研究对象，首先应用聚合酶链反应（PCR）和聚合酶链反应-限制性片段长度多态性（PCR—PFLP）方法确定蚊种，在此基础上，用PCR比较蚊虫细菌拷贝数的异同，同时克隆并酶切4只按蚊中细菌的16SrDNA序列，对酶切结果进行统计分析。结果共明确23只按蚊的种类。不同蚊种DNA中所含细菌拷贝数存在差异，但与按蚊的种类没有关系。4只按蚊DNA中共发现19种细菌16SrDNA的酶切类型。不同中华按蚊个体间存在共同的细菌DNA酶切类型；嗜人按蚊仅呈现2种细菌DNA酶切类型，均与中华按蚊不同。结论嗜人按蚊和中华按蚊中含有的细菌种类存在差异，该项研究为我们进一步研究按蚊中肠细菌是否会影响按蚊对疟原虫的感染性奠定了基础。     

长江三峡库区成蚊种群构成及密度消长

目的了解三峡库区农村的蚊媒数量变化规律及种群构成情况,为做好蚊媒传染病防治和蚊类危害的预测预报提供参考。方法采用诱蚊灯诱捕成蚊并进行分类鉴定统计。结果全年3类环境共计诱捕成蚊30 160只。经鉴定分类,捕获成蚊隶属1目1科2亚科4属5种。其中库蚊亚科库蚊属有致倦库蚊、三带喙库蚊,伊蚊属有白纹伊蚊,阿蚊属有骚扰阿蚊;按蚊亚科按蚊属有中华按蚊。年均成蚊总密度为134.2只/灯晚。致倦库蚊种群数量最多占46.94%,中华按蚊占26.23%,三带喙库蚊占12.94%。结论诱蚊灯法调查获得的蚊群种群密度消长及其种群构成,对三峡库区蚊媒传染病的防治和蚊虫危害治理有重要意义。     

我国蚊虫中昆虫共生微生物Wolbachia感染的研究

目的：研究我国蚊虫中昆虫共生微生物Wolbachia的感染情况。方法：采用依据Wolbachia的wsp基因序列建立的PCR分组检测方法，对我国蚊科中库蚊属、伊蚊属和按蚊属中一些蚊虫种类进行了检测。结果：库蚊属中尖音库蚊复组4个亚种的实验室种群和伊蚊属中的白纹伊蚊的4个地理株种群均有感染，感染的Wolbachia株属B组中的pip组；同时在白纹伊蚊种群中还发现了有A组和B组Wolbachia的双重感染；而同时检测的三带喙库蚊，刺扰伊蚊，埃及伊蚊的2个地理株，中华按蚊和斯氏按蚊没有发现Wolbachia的感染。结论：本研究应用该方法，成功地对我国蚊虫体内感染的Wolbachia株进行了检测与分组。     

云南省东北等地区蚊虫及蚊媒病毒调查研究

目的了解滇东北等地区蚊虫及蚊传虫媒病毒分布特点,为虫媒病毒病防治提供科学依据。方法2009年在滇东北等地区的6个县采集蚊虫标本;蚊虫经分类鉴定后,用细胞培养法分离病毒,对病毒分离物进行分子生物学鉴定。结果共采集到4属（库蚊、按蚊、阿蚊、伊蚊）24种18562只蚊虫,其中三带喙库蚊、中华按蚊为主要蚊种,构成比分别为58．37％和28．45％;从蚊虫标本中分离到15株病毒,经分子生物学鉴定,其中2株（YN0911和YN0967）为基因I型流行性乙型脑炎（乙脑）病毒,均分离自三带喙库蚊;1株（YN0922）为版纳病毒,分离自中华按蚊;12株为淡色库蚊浓核病毒,其中9株分离自三带喙库蚊,3株分离自中华按蚊。结论三带喙库蚊和中华按蚊为调查地区的优势蚊种,并携带乙脯病毒、版纳病毒和淡仁．库蚊浓核病毒：滇东北地区首次分离到乙腩病毒。     

北京市机场口岸蚊类及病原体携带情况调查分析

目的对北京市机场口岸蚊媒本底情况以及蚊媒病原体携带情况进行调查分析,评价北京市是否存在登革热和疟疾传播的蚊媒,为机场口岸蚊媒传播疾病预测预警提供依据。方法采用CO2灯诱法,对捕获的白纹伊蚊进行登革热病毒核酸检测和病毒分离,对中华按蚊进行4种疟原虫核酸检测。结果共捕获成蚊22 715只,密度指数为44.54只/(灯.h),淡色库蚊为优势种占87.95%;其次是三带喙库蚊,占10.64%;中华按蚊、白纹伊蚊分别占1.11%、0.30%。成蚊密度高峰期为8、9月。蚊媒疟原虫、登革热病原携带状况检测结果均为阴性。结论北京市机场口岸存在登革热和疟疾传播的蚊媒,北京市存在由输入性病例(境外感染病例及外省感染病例)引起登革热、疟疾本地传播的风险。应继续加强对机场口岸蚊媒密度监测以及蚊媒病原携带状况监测。     

苏联蚊虫对输入疟原虫株敏感性资料的回顾

<正> 苏联蚊虫对输入人体疟原虫种株敏感性的研究表明,黑小按蚊、麦赛按蚊和萨(哈罗夫)氏按蚊对来自非洲、亚洲和南美洲的间日疟原虫都具有高度的敏感性。这些疟原虫对各种媒介蚊虫适应的程度,都没有大的变化。用由非洲和东南亚输入的恶性疟原虫株感染黑小按蚊和麦赛按蚊,全部实验结果均为阴性。     

2016-2018年北海市疟疾传播媒介监测分析

目的通过分析2016-2018年北海市疟疾传播媒介的监测数据,了解当地疟疾传播媒介种群组成、数量及季节消长情况,为制订疟疾防控措施及策略提供科学依据。方法采用诱蚊灯捕蚊法,在监测点捕获按蚊并进行分类鉴定。结果2016-2018年在各监测点捕获按蚊8488只,以中华按蚊为优势种,占按蚊种群的87.91%;其次是嵌斑按蚊,占按蚊种群的10.84%;其他按蚊数仅占1.25%。按蚊活动季节以5-9月为高峰。结论北海市疟疾传播媒介优势蚊种为中华按蚊,嵌斑按蚊次之,没有发现微小按蚊和嗜人按蚊。     

Morphological characters of adult Anopheles (Nyssorhynchus) marajoara in Venezuela

A morphometric study was carried out to find diagnostic characters with which to update taxonomic keys for field identification of Anopheles (Nyssorhynchus) marajoara and the 3 other sympatric Anopheles (Nyssorhynchus) species (An. darlingi, An. argyritarsis, and An. braziliensis) that occur in Venezuela. Diagnostic random amplified polymorphic DNA-polymerase chain reaction markers from wild-caught specimens showed that An. marajoara was the only species in the Anopheles albitarsis complex collected in Venezuela.     

Geographical distribution of Anopheles darlingi in the Amazon Basin region of Peru

Malaria has reemerged as a significant public health disease threat in Peru, especially within the Amazon Basin region. This resurgence of human cases caused by infection with Plasmodium falciparum and Plasmodium vivax is thought to be associated with the spread of Anopheles darlingi, the principal South American malaria vector, into new areas of the Amazon Basin. However, comprehensive studies of the distribution for this species have not been conducted in Peru for several years, nor are historical accounts accurate enough to determine if An. darlingi was actually present and not collected or misidentified. Therefore, the objective of this study is to define the distribution of An. darlingi as well as obtain data on distribution and abundance of other Anopheles species in this region. Mosquitoes were collected during 2001 in the Departments of Loreto and Ucayali, the two largest Amazonian Departments of Peru. A total of 60,585 specimens representing 12 species of the subgenera Nyssorhynchus and Anopheles were collected at 82 (88.2%) of 93 collecting sites. The majority of mosquitoes obtained were identified as An. benarrochi, comprising 70.7% of mosquitoes collected, followed by An. darlingi (24.0%), Anopheles mattogrosensis (2.4%), and Anopheles triannulatus (1.5%). Anopheles darlingi was collected from 48.8% of sites, indicating that this species is established throughout central Loreto, including further west in the Amazon Basin than previously reported. These data suggest that this species is now found in areas of the Amazon Basin region where it has not been previously reported.     

Host feeding preferences of Anopheles species collected by manual aspiration,mechanical aspiration,and from a vehicle-mounted trap in the Toledo District,Belize, Central America

The host-feeding patterns of Anopheles albimanus, Anopheles vestitipennis, and Anopheles punctimacula from the Toledo District in southern Belize were studied with blood-fed females that were collected by manual aspiration, a backpack aspirator, and a vehicle-mounted trap for sampling in-flight mosquito populations. Female An. vestitipennis collected from both inside and outside house walls by manual aspiration tested positive for human blood meals (88 and 67%, respectively). At increasing distances from the houses, specimens of An. vestitipennis collected from vegetation with the backpack aspirator were equally positive for human and cattle blood (44 and 43%, respectively). In contrast, 68% of the An. albimanus specimens (148) collected by backpack aspiration tested positive for cattle blood. Engorged An. vestitipennis from vehicle-mounted trap collections tested positive for cattle (108) and human (52) blood. Almost all specimens of An. albimanus from these collections were positive for cow (95%). After analyzing the data from the An. vestitipennis samples using the feeding index, the ratio of human blood to all other bloodmeal sources showed indices greater than 1. Both An. albimanus and An. punctimacula fed mostly on cattle and rarely fed on humans. Foraging ratios for the 3 Anopheles species were very similar to the feeding indexes. Ratios based on data from all collection methods showed that An. vestitipennis feeds predominately on humans. The foraging ratios for An. albimanus demonstrated consistent preferences for nonhuman hosts. As with previous studies. An. albimanus seemed to prefer cattle and pigs to almost all other host species.     

Larval salinity tolerances of the sibling species of Anopheles farauti

Experiments conducted with laboratory colonies of the sibling species of Anopheles farauti showed larvae of An. farauti No. 1 had a higher salinity tolerance than larvae of An. farauti No. 2 and An. farauti No. 3. The salinity response of field-collected larvae of An. farauti No. 1 from Cowley Beach, Queensland, Australia was similar to that of larvae from two colonies of this species which originated from Papua New Guinea. These results indicate that An. farauti No. 1 is the species which is likely to be found breeding in brackish water whereas the other species may be restricted to freshwater habitats. Laboratory experiments conducted with the colonies and with specimens collected from three localities in northern Queensland indicated that a simple test, based on exposure of first-instar larvae to sea water for 1 hr, should enable identification of An. farauti No. 1 in the field.     

Identification of three members of the Anopheles funestus (Diptera: Culicidae) group and their role in malaria transmission in two ecological zones in Nigeria

The role of the Anopheles funestus group in malaria transmission was investigated in two ecological zones in Nigeria. Sampling was carried out at four sites each around Ibadan (forest) and Ilorin (savanna). Human landing catches were supplemented with indoor and outdoor resting collections. PCR was used to identify 1848 A. funestus group mosquitoes to species level (749 in the savanna, 1099 in the forest) and three species were identified. In the forest, A. funestus s.s. predominated (55.4%), followed by A. rivulorum (27.6%) and A. leesoni (17.0%). Anopheles funestus was found mostly indoors. Anopheles rivulorum and A. leesoni predominated in outdoor collections (P<0.001). Only Anopheles funestus s.s. was found in the savanna. ELISA analysis of 803 blood meal-positive specimens showed that over half of the blood meals were taken from humans in both ecotypes. The human blood index in A. funestus from the two study areas was similar. Anopheles funestus s.s. was the only species found positive for Plasmodium falciparum using ELISA, with overall infection rates of 2.3% and 1.0% in the forest and savanna respectively. The presence of three A. funestus species in Nigeria emphasizes the desirability of correct species identification within a malaria vector control programme.     

广西微小按蚊种群密度地理分布及种类分子鉴定研究

目的研究20世纪以来广西壮族自治区(广西)微小按蚊的种群密度和地理分布,为疟疾防治提供参考。方法收集广西20世纪50-90年代微小按蚊资料及疟疾发病率,于2004-2010年在不同经纬度原以微小按蚊为主要传播媒介的疟疾流行区收集该蚊成蚊,采用形态学和PCR方法鉴定采集的微小按蚊样品。结果1957-1998年对全自治区不同经纬度媒介按蚊调查,92个县中有56个县存在微小按蚊;2004-2007年在该蚊活动频繁的36个县的乡村收集按蚊,仅在20个县40个媒介点采集到微小按蚊244只;采用种类分子鉴定,除百色市旺甸村有微小按蚊种类A存在外,其他地区均为微小按蚊种类C。2008年后全自治区各县疟疾疫情发病率已降至0.1/万。结论目前在广西存在微小按蚊种类A和C两种,以种类C为主;全自治区不同经纬度的微小按蚊种群密度和分布范围已经明显减少,该蚊有可能不再是该区域疟疾传播的主要媒介。     

Malaria vectors on Buka and Bougainville Islands,Papua New Guinea

Anophelines were sampled from 82 locations on Buka and Bougainville islands in Papua New Guinea by larval collections, carbon dioxide-baited mosquito traps, and human biting catches. Anopheles farauti s.s. was collected in larval surveys but infrequently in mosquito traps on both islands; on Buka Island this species was readily collected in human biting catches. Anopheles farauti 2 was commonly collected in larval surveys on both islands; however, it was not collected in either mosquito traps or human biting catches. Anopheles punctulatus was found only on Buka Island, where it was commonly collected as larvae, but rarely in human biting catches and mosquito traps. Anopheles lungae was collected as larvae from only 1 site on Bougainville. Anopheles farauti s.s. fed consistently throughout the night (1900-0600 h); small peaks at midnight and dawn were not statistically significant. Of 1,156 An. farauti s.s. specimens examined by enzyme-linked immunosorbent assay for malaria sporozoites, 20 were found to be positive; 12 were positive for Plasmodium falciparum and 8 were positive for P. vivax (247 variant = 5; 210 variant = 3). Anopheles farauti s.s. seems to be the major malaria vector on these islands, whereas An. punctulatus may play a minor role on Buka Island. Anophele jarauti 2 is unlikely to be involved in malaria transmission on Buka or Bougainville islands.     

A description and morphometric comparison of eggs of species of the Anopheles gambiae complex.

Eggs of the 6 named species of the Anopheles gambiae complex are described from scanning electron micrographs of specimens obtained from laboratory colonies or wild-caught females. Morphometric measurements of eggs from 5 sources of Anopheles arabiensis, 2 of Anopheles gambiae, one of Anopheles quadriannulatus, 2 of Anopheles bwambae, 2 of Anopheles merus, and one of Anopheles melas are compared, and relationships are analyzed by multivariate statistics. No morphologic characters were species-diagnostic, although tendencies of the saltwater species An. merus and An. melas to have wider decks and shorter floats were confirmed. Species and populations overlapped considerably in principal components and discriminant function analyses based on 10 attributes of eggs. Nevertheless, discriminant functions revealed similarities in eggs of species believed to be most closely related, namely, An. gambiae and An. arabiensis, An. merus and An. melas, and An. quadriannulatus and An. bwambae.     

Molecular evidence supports that Anopheles anthropophagus from China and Anopheles lesteri from Japan are the same species

The Hyrcanus group of Anopheles consists of many related species, of which An. sinensis, An. lesteri, and An. anthropophagus are known as malaria vector species. It is not possible to identify these species morphologically in the adult and larval stages. Nucleotide sequence alignment of 2nd internal transcribed spacer (ITS2) regions from 4 specimens of An. lesteri collected in Japan, 2 specimens of An. anthropophagus collected in China, and 1 specimen of An. sinensis collected in Korea were sequenced and compared. Sequences of ITS2 regions varied only at 4 sites between An. lesteri and An. anthropophagus, and individual variations among each An. lesteri and An. anthropophagus were found at 5 and 7 sites, respectively, whereas sequences varied at 161 sites between An. lesteri and An. sinensis. This molecular evidence strongly supports that An. lesteri from Japan and An. anthropophagus from China are the same species.     

Some entomological observations on malaria transmission in a remote village in northwestern Thailand

Anopheline mosquitoes and their relation to malaria transmission were studied during the months of March, May and July in the Karen village of Mae Tha Waw located in the northwestern mountains of Tak Province. Thirteen species were captured on human bait during 80 man-nights of collecting. Four additional species were collected during routine larval surveys. Anopheles minimus and An. maculatus comprised 92.5% of the specimens captured biting man. Anopheles minimus and An. nivipes were implicated as vectors based on the detection of sporozoite infections using enzyme-linked immunosorbent assays for Plasmodium falciparum and P. vivax. Anopheles dirus was rarely encountered and probably played little part in transmission in Mae Tha Waw during the period of study. Information is provided on nightly biting activity, incidence of disease, infectivity and larval bionomics.