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1.
笔者于1983年在辽宁千山对黄斑伊蚊孳生习性及季节消长作了调查,现报告如下:一、孳生习性:对山间溪流、池塘、石穴、陶瓷容器、金属容器、水泥池(槽)、树洞、泉水坑等场所作了黄斑伊蚊幼虫的调查。共采样198份,孳生率30.81%。其中石穴孳生率29.41%(20/68);树洞孳生率55.56%(35/63);陶瓷容器孳生率50.00%(3/6);金属容器(铁锅、铁罐头盒)孳生率23.08%(3/13)。山间溪流21份,池塘21份,水泥池(槽)5份,泉水坑1份等场所都没有采到。树洞、石穴孳生主要蚊种的组成如下:树洞,共孵出标本237只。其中黄斑伊蚊占72.58%(♀96、♂76);白雪伊蚊占13.50%(♀1…  相似文献   

2.
1979年5月下旬至9月末,作者在辽宁省千山做了蚊虫密度调查;并于同年8月7日9时至8日9时和8月16日14时至17日14时,作了昼夜活动节律的调查。 1.在捕获的521只(345,176)蚊虫中,黄斑伊蚊352只(占67.56%),朝鲜伊蚊77只(占14.77%),仁川伊蚊45只(占8.63%),其他蚊种(包括白雪伊蚊、中华按蚊、竹生杵蚊等)共47只。因而黄斑伊蚊是千山地区的优势蚊种。  相似文献   

3.
登革Ⅱ型病毒经白纹伊蚊滞育卵的传递   总被引:7,自引:1,他引:6  
采用C6/36细胞培养分离病毒的方法检测感染登革Ⅱ型病毒的白纹伊蚊Aedes albopictus滞育卵孵化的F1代蚊虫感染率,从第一个生殖营养周期子代蚊虫中未分离到病毒,第二与第三生殖营养周期子代蚊虫最低感染率没有显著性差异(χ2=0.01,P>0.0 5),感染子代的批阳性率为9.1%,最低感染率为1∶330;间接免疫荧光检测结果表明感染登革Ⅱ型病毒的白纹伊蚊滞育卵孵化的子代成蚊能通过叮咬将登革病毒传播给敏感乳鼠。这些研究结果表明登革病毒能在媒介滞育卵内存活并传至子代,子代蚊虫能通过叮咬敏感宿主水平传播病毒。  相似文献   

4.
致倦库蚊(Culex quinquefasciatus)是西尼罗病毒(West Nile virus,WNV)、圣路易斯脑炎病毒等重要的媒介。蚊浓核病毒(Mosquito densovirus,MDV)是特异性感染蚊类的病毒,对蚊虫具有明显的致病性。为研究MDV对致倦库蚊的致病效应,我们使用不同浓度埃及伊蚊浓核病毒(Aedes aegypti densovirus,AaeDV)感染致倦库蚊不同发育阶段的幼虫、蛹与成蚊,测定其感染率与死亡率,结果证实AaeDV对致倦库蚊1~2龄幼虫、3~4龄幼虫、蛹和雌雄成蚊的感染率分别为93.33%±2.49%、66%±3.74%、2.67%±0.94%、23.33%±3.40%和24.00%±1.63%,感染率与其发育阶段有关而与性别无关。AaeDV对幼虫的杀伤效果具有剂量依赖性,且与发育阶段有关,在1×1011拷贝/mL浓度下,新孵化龄幼虫和3~4龄幼虫的死亡率高达95.33%±0.74%和61.67%±2.07%。因此AaeDV对致倦库蚊具有生物防制的潜在价值。  相似文献   

5.
近年来福建省登革热(Dengue fever,DF)输入性病例持续存在,且登革热的主要传播媒介白纹伊蚊在全省内广泛分布,为了解福建省福州市登革热的媒介白纹伊蚊携带登革病毒(Dengue virus,DENV)状况,2017年10月7日在福州市台江区元一花园小区内开展伊蚊监测,采用双层叠帐法捕获255只白纹伊蚊蚊体研磨液上清提取核酸后用实时荧光RT-PCR法检测DENV特异性核酸,将检测阳性的蚊体研磨液上清接种C6/36细胞进行病毒分离,成功分离到1株DENV病毒株mosquito13/Fujian/2017;经实时荧光RT-PCR法鉴定所分离病毒株的血清型为I型;利用型特异性引物通过RT-PCR扩增病毒E基因并测序进行分子遗传特性分析;E基因核苷酸和氨基酸同源性分析显示,该毒株与2017年10月17日同小区本地登革热病例血清中分离得到的登革毒株E基因序列完全一致,与越南2014年分离株KT825033/Vietnam/2014核苷酸(99.7%)和氨基酸(99.8%)同源性最高;系统进化树分析表明所分离登革病毒毒株的基因型为I型,与东南亚地区的越南,泰国,柬埔寨等国家进化关系相近,可能输入来源于东南亚国家。本研究证实了登革热外潜伏期的存在以及白纹伊蚊在登革热疫情传播过程中的媒介作用,提示在登革热的防控工作中媒介登革病毒监测、检测的重要性,也提示福建省需要加强输入来源监测,特别是东南亚入境人员的监测。  相似文献   

6.
【目的】建立白纹伊蚊Aedes albopictus抗溴氰菊酯的蚊虫品系,对比白纹伊蚊敏感株和抗性株对登革病毒的易感性差异。【方法】采用浸渍法测定溴氰菊酯对白纹伊蚊幼虫的半数致死浓度(LC_(50));再以LC_(50)水平的溴氰菊酯对白纹伊蚊幼虫进行群体筛选至第11代,并通过接触筒法检测各代成蚊抗性。以白纹伊蚊敏感株和获得的抗性株(第9代)雌蚊吸食含2型登革病毒(DENV-2)的血餐,于感染后0,4,7和10 d解剖蚊虫,收集中肠、卵巢和唾液腺,通过RT-PCR和实时荧光定量PCR分别检测各组织的DENV-2病毒感染率和感染量。【结果】白纹伊蚊经溴氰菊酯筛选至第9代后抗性趋于稳定。第9代抗性株幼虫的LC_(50)为0.053 mg/L,抗性倍数为10.58,成蚊生测的蚊虫死亡率为80%,已达到中度抗性。感染后0 d,所有蚊虫的中肠均可测得DENV-2,而且抗性株的平均病毒感染量高于敏感株;后续时间点敏感株与抗性株蚊虫中肠均保持92.75%~97.18%的病毒感染率,且二株之间无显著性差异(P0.05)。感染后4 d,两株蚊虫的卵巢中均可检测到DENV-2,感染后7 d和10 d的卵巢病毒感染率均显著高于4 d时(P0.05),但在7 d和10 d两个时间点,敏感株和抗性株之间均无统计学差异(P0.05),然而抗性株平均病毒感染量在每一个时间点都显著高于敏感株(P0.05)。蚊虫唾液腺于感染后7 d检测到DENV-2,10 d时唾液腺的病毒感染率无明显升高且两株蚊虫之间病毒感染率和感染量均无统计学差异(P0.05)。【结论】经溴氰菊酯的筛选使白纹伊蚊幼虫及成蚊抗性水平逐渐升高,建立了白纹伊蚊抗溴氰菊酯的实验室品系。DENV-2对白纹伊蚊抗性株和敏感株各个组织的感染率相近,但感染量有所不同,说明对溴氰菊酯有中度抗性的白蚊伊蚊对登革病毒的易感性在一定程度上发生了改变。  相似文献   

7.
以上海常见蚊种:淡色庙蚊、三带喙库蚊、中华按蚊、白纹伊蚊、骚扰阿蚊和棕垲麻蚁等6咱,在相似条件下进行对犬丝虲的人工感染试验。结果证明犬丝虫能在白纹伊蚊、中华按蚊、淡色库蚊及三带喙庸蚊完垒傲育;骚援阿蚊吸血後,所有进入马氏管中的微丝蚴全成角質化,不能发育;棕尾麾蚊不能吸血,无法观察。各试验种中以感染率论,淡色庙蚊最高,中摹按蚊和白纹伊蚊次之,三带喙庵蚊最低。以发育率论,中华按蚊最高,白纹伊蚊次之,淡色库蚊和三带喙庳蚊最低。以蚊虫存活率论,淡色库蚊和白纹伊蚊最高,三带喙应蚊次之,中莘按蚊最低。根攘Kartman氏(1954)所建议的实验戚染指敷比较各蚊种的感受力,试验蚊植中以白纹伊蚊最高,淡色库蚊和中华按蚊次之,三带喙库蚊最低。各蚊种的吸犬血率,在实验室条件下,以白纹伊蚊为最高,中华按蚊次之,三带喙库蚊及骚扰阿蚊及淡色库蚊次之。上述试验结果指出四种蚊虫中,以白牧伊蚊为最適宜的试验媒介,也可能是自然媒介;中华按蚊灾之,其他二种库蚊更次之,似不重要。  相似文献   

8.
1985年4~11月在湖北神农架林区共发现蚊虫7属34种,包括按蚊属3种,伊蚊属17种)库蚊属10种,阿蚊属、直脚蚊属、杵蚊属和巨蚊属各1种。其中单环伊蚊(Aedesunicinctus,为我国新纪录,阿萨姆伊蚊(Ae.assamensis),金背伊蚊(Ae.gilli)、金叶伊蚊(Ae.oreophiles)、美腹伊蚊(Ae.pulchriventer)和金毛巨蚊(Toxorhynchitesaurifluus)为湖北省新纪录。原见于文献报道的黄边巨蚊(Tx.edwardsi)经核对实为金毛巨蚊之误。单环伊蚊1985年5月中旬至6月下旬在林区松柏镇附近的山坡上(海拔800—1,200米)的树洞内采集到,其主要特征有:幼虫头毛4细小,常分2—3枝…  相似文献   

9.
采用大链壶菌在实验室内对白纹伊蚊及其它几种贵州蚊虫的幼虫进行杀灭试验。白纹伊蚊的感染率为25—89%,而致倦库蚊的感染率可达90—100%。实验结果为大链壶菌的宿主记录新增加一个属和五个种。  相似文献   

10.
采用生化技术进行蚊虫分类学和亲缘关系的研究,国外已有不少报道。Robert等综述了昆虫同工酶及其意义;McDonald等和我国的缪建吾都分别报道了白纹伊蚊的酯酶及可溶性蛋白的电泳图谱,但目前尚未见到对不同地理株的同种蚊虫的生化分析结果。我们采用聚丙烯酰胺凝胶电泳(PAGE)和等电点聚焦电泳(IFE),先后对三属六种十二株伊蚊、库蚊及按蚊作了酯酶、α-磷酸甘油脱氢酶及蛋白的生化分析。现将结果报告如下。一、材料和方法 1、实验材料采用本所饲养的白蚊伊蚊[Aedes albopictus(Skuse)]广州株、南宁株、上海株、海南株、云南株及宜兴株;埃及伊蚊[Aedes aegypti(Linnaeus)]Bora-Bora株和海南株;黄斑伊蚊(Aedes flavopitus Yamada)。淡色库蚊  相似文献   

11.
Abstract. The incidence of dengue haemorrhagic fever (DHF) in Thailand has increased cyclically since the first recognized outbreak in 1958. Without an effective vaccine against dengue, and considering the clinical difficulty of treating DHF cases, vector control is needed to prevent dengue transmission. Since the establishment of the WHO Aedes Research Unit in 1964, continued since 1973 as the WHO Collaborating Centre at the Department of Medical Research in Bangkok, much operational research has been carried out in Thailand on the bionomics and control of dengue vectors: Aedes aegypti and Ae.albopictus. This review shows that, as in most other countries, dengue vector control programmes in Thailand make little use of the procedures arising from research, nor have they reduced the upward trend of dengue or prevented DHF outbreaks. Implications of the reluctance to use results of operational research on vector control are considered and remedial suggestions made.  相似文献   

12.
登革热媒介昆虫抗药性的研究进展   总被引:7,自引:0,他引:7  
近年来,登革热在全球的流行迅速增长,埃及伊蚊Aedes aegypti(L.)和白纹伊蚊Aedes albopictus(Skuse)是登革热传播的主要媒介。目前,化学防治仍然是防治蚊虫的主要手段,每年化学杀虫剂的大量使用直接或间接地导致其产生了抗药性。关于埃及伊蚊和白纹伊蚊的抗药性研究,主要集中于DDT、有机磷和拟除虫菊酯类杀虫剂导致的抗药性,并已深入到抗药性分子机理的研究。文章就埃及伊蚊和白纹伊蚊对杀虫剂诱导的抗药性现状及抗性机理的研究进展进行综述。  相似文献   

13.
Dengue, the most important human arboviral disease, is transmitted primarily by Aedes aegypti and, to a lesser extent, by Aedes albopictus. The current distributions of these invasive species overlap and are affected by interspecific larval competition in their container habitats. Here we report that competition also enhances dengue infection and dissemination rates in one of these two vector species. We determined the effects of competition on adult A. aegypti and A. albopictus, comparing their susceptibility to infection with a Southeast Asian strain of dengue-2 virus. High levels of intra- or interspecific competition among larvae enhanced the susceptibility of A. albopictus to dengue virus infection and potential for transmission, as indicated by disseminated infections. Doubling the number of competing larvae (A. albopictus or A. aegypti), led to a significant (more than 60%) increase in the proportion of A. albopictus with disseminated dengue-2 infection. Competition-enhanced vector competence appears to result from a reduction in 'barriers' (morphological or physiological) to virus infection and dissemination and may contribute to the importance of A. albopictus in dengue transmission. Similar results for other unrelated arboviruses suggest that larval competition, common in mosquitoes, should be considered in estimates of vector competence for pathogens that infect humans.  相似文献   

14.
Counts of immature stages of the mosquito Aedes aegypti have been used to calculate several entomological indices of dengue vector abundance. Some studies have concluded that these indices can be used as indicators of dengue epidemic risk, while other studies have failed to find a predictive relationship. Ecological niche models have been able to predict distributional patterns in space and time, not only of vectors, but also of the diseases that they transmit. In this study, we used Landsat 7 ETM+ images and two niche-modeling algorithms to estimate the local-landscape ecological niche and the dynamics of Ae. aegypti larval habitats in Bello, Colombia, and to evaluate their potential spatial and temporal distribution. Our models showed low omission error with high confidence levels: about 13.4% of the area presents conditions consistently suitable for breeding across the entire study period (2002-2008). The proportion of neighborhoods predicted to be suitable showed a positive association with dengue case rates, whereas the vector-focused Bretau index had no relationship to case rates. As a consequence, niche models appear to offer a superior option for predictive evaluation of dengue transmission risk and anticipating the potential for outbreaks.  相似文献   

15.
The Asian tiger mosquito Aedes albopictus (Skuse) (Diptera: Culicidae), native to Southeast Asia, has extended its geographical distribution to invade new temperate and tropical regions. This species was introduced in 1990 to Italy and has since become the main pest in urban settings. It was incriminated as a principal vector in the first European outbreak of chikungunya virus (CHIKV) in the province of Ravenna (Italy) in 2007. This outbreak was associated with CHIKV E1-226V, efficiently transmitted by Ae. albopictus . The occurrence of this outbreak in a temperate country led us to estimate the potential of Ae. albopictus to transmit CHIKV and dengue virus (DENV), and to determine the susceptibility to CHIKV of other mosquito species collected in northern Italy. Experimental infections showed that Ae. albopictus exhibited high disseminated infection rates for CHIKV (75.0% in Alessandria; 90.3% in San Lazzaro) and low disseminated infection rates for DENV-2 (14.3% in San Lazzaro; 38.5% in Alessandria). Moreover, Ae. albopictus was able to attain a high level of viral replication, with CHIKV detectable in the salivary glands at day 2 after infection. In addition, the other three mosquito species, Anopheles maculipennis Meigen, Aedes vexans vexans (Meigen) and Culex pipiens L., showed variable susceptibilities to infection with CHIKV, of 0%, 7.7% and 0–33%, respectively. This information on vector competence is crucial in assessing the risk for an outbreak of CHIKV or DENV in Italy.  相似文献   

16.
The aim of this review was to compare the effects of different dengue vector control interventions (i.e. biological control, chemical control, environmental management and integrated vector management) with respect to the following entomological parameters: Breteau index (BI), container index (CI), and house index (HI). We systematically searched PubMed, ISI Web of Science, Science Direct, the Dengue Bulletin of the World Health Organization and reference lists of retrieved articles on dengue vector control interventions in developing countries. We extracted data on the effectiveness of different dengue vector control interventions (defined as the relative reduction of an entomological measure caused by the intervention compared with the control or pre-intervention phase) and calculated a measure of combined relative effectiveness, with 95% confidence intervals (95% c.i.). We identified 56 publications covering 61 dengue vector control interventions. Integrated vector management was found to be the most effective method to reduce the CI, HI and BI, resulting in random combined relative effectiveness values of 0.12 (95% c.i. 0.02-0.62), 0.17 (95% c.i. 0.02-1.28) and 0.33 (95% c.i. 0.22-0.48), respectively. Environmental management showed a relatively low effectiveness of 0.71 (95% c.i. 0.55-0.90) for the BI, 0.49 (95% c.i. 0.30-0.79) for the CI and 0.43 (95% c.i. 0.31-0.59) for the HI. Biological control (relative effectiveness for the CI: 0.18) usually targeted a small number of people (median population size: 200; range 20-2500), whereas integrated vector management focused on larger populations (median: 12 450; range: 210-9 600 000). In conclusion, dengue vector control is effective in reducing vector populations, particularly when interventions use a community-based, integrated approach, which is tailored to local eco-epidemiological and sociocultural settings and combined with educational programmes to increase knowledge and understanding of best practice. New research should assess the density-dependent effectiveness of each control measure in order to estimate whether reducing vector numbers has an impact on dengue transmission when populations are at a critical threshold.  相似文献   

17.
Although the mosquito midgut is the primary site of bloodmeal storage and the first line of defence against pathogenic infection, little is known about its proteic composition at a time when an increasing number of proteins are reported to impair viral infection. Aedes albopictus Skuse (Diptera: Culicidae) is an important vector of the dengue virus. We compared 2-dimensional protein profiles of the adult midgut in this species, taking into account bloodmeal status. The comparison of profiles from sugar-fed and blood-fed females showed that a considerable number of proteins were present in both midguts. In addition, one set of proteins was present only after sugar intake and another set only after blood intake. The comparison of profiles of blood-fed midguts and dengue virus-2 infected blood-fed midguts revealed that at least six proteins were present only in the infected midguts. These results are discussed in the context of the identification of midgut proteins involved in the dengue virus infection process.  相似文献   

18.
Dengue remains one of the major public concerns as the virus eludes the immune response. Currently, no vaccines or antiviral therapeutics are available for dengue prevention or treatment. Immunosuppressive drug FK506 shows an antimalarial activity, and its molecular target, FK506‐binding protein (FKBP), was identified in human Plasmodium parasites. Likewise, a conserved FKBP family protein has also been identified in Aedes aegypti (AaFKBP12), which is expected to play a similar role in the life cycle of Aedes aegypti, the primary vector of dengue virus infection. As FKBPs belong to a highly conserved class of immunophilin family and are involved in key biological regulations, they are considered as attractive pharmacological targets. In this study, we have determined the nuclear magnetic resonance solution structure of AaFKBP12, a novel FKBP member from Aedes aegypti, and presented its structural features, which may facilitate the design of potential inhibitory ligands against the dengue‐transmitting mosquitoes. Proteins 2012;. © 2012 Wiley Periodicals, Inc.  相似文献   

19.
The transmission of dengue, the most important arthropod‐borne viral disease in Brazil, has been intensified over the past decades, along with the accompanying expansion and adaptation of its Aedes vectors. In the present study, we mapped dengue vectors in Ouro Preto and Ouro Branco, Minas Gerais, by installing ovitraps in 32 public schools. The traps were examined monthly between September, 2011 through July, 2012 and November, 2012 to April, 2013. The larvae were reared until the fourth stadium and identified according to species. The presence of dengue virus was detected by real time PCR and agarose gel electrophoresis. A total of 1,945 eggs was collected during the 17 months of the study. The Ovitrap Positivity Index (OPI) ranged from 0 to 28.13% and the Eggs Density Index (EDI) ranged from 0 to 59.9. The predominant species was Aedes aegypti, with 84.9% of the hatched larvae. Although the collection was low when compared to other ovitraps studies, vertical transmission could be detected. Of the 54 pools, dengue virus was detected in four Ae. aegypti pools.  相似文献   

20.
In recent decades, the Asian tiger mosquito expanded its geographic range throughout the northeastern United States, including Pennsylvania. The establishment of Aedes albopictus in novel areas raises significant public health concerns, since this species is a highly competent vector of several arboviruses, including chikungunya, West Nile, and dengue. In this study, we used geographic information systems (GIS) to examine a decade of colonization by Ae. albopictus throughout Pennsylvania between 2001 and 2010. We examined the spatial and temporal distribution of Ae. albopictus using spatial statistical analysis and examined the risk of dengue virus transmission using a model that captures the probability of transmission. Our findings show that since 2001, the Ae. albopictus population in Pennsylvania has increased, becoming established and expanding in range throughout much of the state. Since 2010, imported cases of dengue fever have been recorded in Pennsylvania. Imported cases of dengue, in combination with summer temperatures conducive for virus transmission, raise the risk of local disease transmission.  相似文献   

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