从云南省宾川县蝙蝠体内分离到乙型脑炎病毒

１９９１年９月，从捕自云南省宾川县的１３２只双色帝蝙蝠和棕果蝙蝠体内分离到４株病毒。经电镜观察、血凝抑制试验和单克隆抗体免疫荧光试验证实为乙型脑炎病毒。结果表明蝙蝠在乙型脑炎病毒保存和传播中起重要作用。     

内蒙古大兴安岭林区森林脑炎自然疫源地调查报告

１９９２－１９９３年，我们对内蒙古大兴安岭林区进行森林脑炎自然疫源地调查。选择南，北，中三个方位，共捕蜱９８２只，分离到３株森林脑炎病毒（编号９３０２，９３０５，９３０８）。并从可疑森脑死亡者脑组织中分离到１株森林脑炎病毒（９３Ｈ）。从而证实内蒙古大兴安岭为森林脑炎自然疫源地。     

果蝠与人类(新现)病毒性疾病

蝙蝠是多种人兽共患疾病病毒的储存宿主,迄今为止,在蝙蝠体内分离到80多种病毒。目前研究发现有25个病毒科能够感染脊椎动物,其中有10个科和蝙蝠有关,主要是RNA病毒与蝙蝠有关,在感染脊椎动物的16个RNA病毒科中,至少有9个科可感染蝙蝠,如罗斯河病毒(Ross River virus．RRV)、乙型脑炎病毒、西尼罗河病毒(West Nile Virus,WN)、狂犬病毒(rabies)等。在众多的蝙蝠科中,     

云南省德宏州蚊虫分布特点及乙型脑炎病毒分离

１９８３年５月以及１９８４年和１９８９年７￣８月，在云南省德宠州路西，瑞丽和盈江三县，市捕获成年雌性蚊虫９属４４种１９０８３只。三带喙库蚊，霜背库蚊，棕头库蚊和中华按蚊是农村畜圈的主要蚊种。伪白纹伊蚊和白纹伊蚊是野外竹林区的优势蚊种。对所获蚊虫用Ｃ６／３６细胞和乳鼠方法分离病毒，结果从三带喙库蚊中分离到乙型脑炎病毒２株，从霜背库蚊，白纹伊蚊和窄翅伊蚊中各分离出１株乙型脑炎病毒。分析认为，三带喙库蚊     

云南省洱源县流行性乙型脑炎暴发流行的病原分离与鉴定

１９９１年７￣１０月,云南省洱源县发生流行性乙型脑炎暴发流行,采用滤过性试验,免疫荧光试验,交互ＨＩ试验,交互ＣＦ试验和中和试验方法,对从该县流行期采集的病人血清分离的２株病毒和从三带喙库蚁分离到的２株病毒进行鉴定,证实４株病毒均为流行性乙型脑炎病毒,从病原学证实为流行性乙型脑炎暴发流行,同时还查明了三带喙库蚊是本次乙型脑炎流行的主要传播媒介。     

福建省首次从病人血清及蚊体分离出登革病毒的研究

目的　１９９９ 年入夏以来, 我省某地发生不明原因发热、头痛、肌痛、乏力、皮疹等症状的病人, 拟诊为登革热。为了从病原学上证实, 我们进行了病毒分离, 为防治工作提供科学依据。方法　应用早期病人血清７ 份, 白纹伊蚊１ 份经处理后接种Ｃ６／３６ 细胞, 并应用恢复期病人血清、双相血清、免疫血清及单克隆抗体进行免疫荧光法鉴定及分型。结果　在７份早期病人血清中经２ ～３ 代分离出５ 株登革病毒, 并从白纹伊蚊体内分离出１ 株登革病毒。结论　此分离的毒株经鉴定均为登革ＩＩ型病毒。此系福建省首次从病人血清及蚊媒体内分离出病毒的报告。不仅为防制工作提供科学依据, 而且为今后的研究奠定了基础。     

首次从家燕分离到1株乙型脑炎病毒

首次从家燕分离到１株乙型脑炎病毒刘行知，袁庆虹，李兆祥，白登云，张海林（云南省流行病防治研究所，大理市６７１０００）李炎，杨灿辉，李连英，李廷芬，石学雷（云南省宾川县卫生防疫站）关键词乙型脑炎，病毒．，家燕，云南省１９９１年７～１０月云南省宾川县发生...     

猪源性乙型脑炎病毒分离株全基因序列测定和分析

[摘要] 目的 了解猪源性乙型脑炎病毒（乙脑病毒）的基因特征。方法 对猪源性乙脑病毒株（JX61）进行全基因组序列测定和基因进化特性的分析。结果 猪源性乙脑病毒JX61株全基因组全长均为10964个核苷酸,含有一个开放阅读框架,编码3432个氨基酸。与GenBank中选择的41株乙脑病毒全基因序列比较发现,其核苷酸同源为83.6-99.3%,氨基酸总体同源性为94.9%-99.6%。通过全基因序列进行系统进化分析均显示该毒株属于基因I型乙脑病毒。结论 猪源性乙脑病毒JX61株属于基因I型,与国内分离株XJP613关系最为接近。提示猪体内的乙脑病毒基因型别有了新的变化,这也是浙江省在猪机体第一次分离基因I型乙脑病毒。     

云南首次分离到辛德毕斯（Sindbis）、巴泰（Batai）和Coiti病毒

目的了解云南省虫媒病毒分布情况，为防治提供依据。方法在云南省思茅地区和西双版纳州采集蚊虫以及发热病人血清。液氮冻存。标本常规处理，接种C6／36细胞和乳鼠以分离病毒，并用血清学和分子生物学方法对分离到的病毒进行鉴定。同时采集发热病人和健康人血清，用ELISA和血凝抑制试验检测病毒抗体。结果从西双版纳发热病人血清中分离到1株辛德毕斯(Sindbis)病毒，从澜沧县菲律宾按蚊中分离到1株巴泰(Batai)病毒，从思茅市翠云区和澜沧县三带喙库蚊、中华按蚊、菲律宾按蚊、迷走按蚊等蚊虫中分离到10株Colti病毒。血清抗体检查，西双版纳发热病人血清中辛德毕斯病毒抗体阳性率为2．50％(3／120)，巴泰病毒抗体阳性率为4．17％(5／120)；思茅和西双版纳地区健康人血清中辛德毕斯病毒抗体阳性率为1．93％(11／571)，其中澜沧、思茅、景洪、勐腊和勐海的阳性率依次为4．55％(6／132)、0．89％(1／112)、1．25％(2／160)、1．96％(2／102)和0．00％(0／65)；西双版纳发热病人和脑炎病人血清中还检测出Colti病毒抗体。结论云南省分布有经蚊虫传播的辛德毕斯、巴泰和Colti病毒。当地人群中也存在该病毒自然感染。今后应加强这3种虫媒病毒病的调查研究和防治工作。     

1例小肠结肠炎耶尔森菌人畜感染情况研究

目的 研究小肠结肠炎耶尔森菌(Y.e)人畜感染情况,探索传染来源。方法 采集腹泻病人粪便标本和猪咽拭子进行Y.e常规分离鉴定。对分离株进行血清学分型,用PCR方法检测毒力基因,用脉冲场凝胶电泳(PFGE)进行分子分型。结果 从150例腹泻病人中分离到Y.e 3株,其中1株血清型为O∶3;从该O∶3株病患老家采集的222份猪咽拭子分离到Y.e 14株,都为O∶3血清型;PFGE分子分型显示病人体内分离到的致病Y.e与家猪分离株有较高的同源性。结论 证实1例小肠结肠炎耶尔森菌从家猪传染人的病例,并发现Y.e在治愈病人体内至少存在了2个月。     

云南省西双版纳州蚊虫分布特点及与虫媒病毒的关系

１９８１、１９８２、１９８３、１９８６、１９８７和１９８８年在西双版纳州景洪、勐海和勐腊县（市）捕获成年雌性蚊虫８属３４种３４５０８只。夜晚在农村畜圈及其周围采获蚊虫２１种,优势蚊种为棕头库蚊和三带喙库蚊;白天在野外竹林采获蚊虫２５种,优势蚊种为贺斑伊蚊和白蚊伊蚊。从三带喙库蚊（８株）、霜背库蚊（４株）、伪杂鳞库蚊（３株）、环带库蚊（１株）、棕头库蚊（１株）、中华按蚊（３株）、刺扰伊蚊（２株）、白     

Growth characteristics of the chimeric Japanese encephalitis virus vaccine candidate, ChimeriVax-JE (YF/JE SA14--14--2), in Culex tritaeniorhynchus, Aedes albopictus, and Aedes aegypti mosquitoes

The Japanese encephalitis (JE) virus vaccine candidate, ChimeriVax-JE, which consists of a yellow fever (YF) 17D virus backbone containing the prM and E genes from the JE vaccine strain JE SA14--14--2, exhibits restricted replication in non-human primates, producing only a low-level viremia following peripheral inoculation. Although this reduces the likelihood that hematophagous insects could become infected by feeding on a vaccinated host, it is prudent to investigate the replication kinetics of the vaccine virus in mosquito species that are known to vector the viruses from which the chimera is derived. In this study ChimeriVax-JE virus was compared to its parent viruses, as well as to wild-type JE virus, for its ability to replicate in Culex tritaeniorhynchus, Aedes albopictus, and Aedes aegypti mosquitoes. Individual mosquitoes were exposed to the viruses by oral ingestion of a virus-laden blood meal or by intrathoracic (IT) virus inoculation. ChimeriVax-JE virus did not replicate following ingestion by any of the three mosquito species. Additionally, replication was not detected after IT inoculation of ChimeriVax-JE in the primary JE virus vector, Cx. tritaeniorhynchus. ChimeriVax-JE exhibited moderate growth following IT inoculation into Ae. aegypti and Ae. albopictus, reaching titers of 3.6-5.0 log(10) PFU/mosquito. There was no change in the virus genotype associated with replication in mosquitoes. Similar results were observed in mosquitoes of all three species that were IT inoculated or had orally ingested the YF 17D vaccine virus. In contrast, all mosquitoes either IT inoculated with or orally fed wild-type and vaccine JE viruses became infected, reaching maximum titers of 5.4-7.3 log(10) PFU/mosquito. These results indicate that ChimeriVax-JE virus is restricted in its ability to infect and replicate in these mosquito vectors. The low viremia caused by ChimeriVax-JE in primates and poor infectivity for mosquitoes are safeguards against secondary spread of the vaccine virus.     

Correlation of population indices of female Culex tritaeniorhynchus with Japanese encephalitis viral activity in Kapuk, Indonesia

Nineteen consecutive monthly light trap collections of mosquitoes were made between October 1978 and April 1980 in Kapuk, Indonesia. Kapuk is a small suburb of Jakarta where pigs are raised in close proximity to rice paddies which are breeding sites for Culex tritaeniorhynchus. Japanese encephalitis (JE) virus is believed to be endemic and has been recovered from mosquitoes and pigs in the area on several occasions. A total of 18,435 female Cx. tritaeniorhynchus were allocated to 359 pools of approximately 50 per pool. Virus isolations were attempted in both Vero and BHK-21 cells and agents producing cytopathic effect were identified in a micro-neutralization test. Nineteen strains of JE were recovered from the 359 pools of Cx. tritaeniorhynchus tested. The light trap index of female Cx. tritaeniorhynchus (X) and the relative frequency of pools positive for JE (Y) for each month of the study were plotted and correlation coefficients (r) calculated after transforming the mosquito population data logarithmically and the relative frequencies of isolation by arcsine square root. The close fit of the data (p less than 0.001) to an inverse linear model (1/y = a + b log10X) suggests a close dependence of JE viral activity on the population dynamics of Cx. tritaeniorhynchus. Three additional strains of JE were recovered from other Culex spp. at the same study site. One strain each was isolated from individual pools of Cx. gelidus, Cx. vishnui and Cx. fuscocephala. Cx. tritaeniorhynchus was more frequently infected with JE than the other species tested.     

Distribution of mosquitoes and mosquito-borne arboviruses in Yunnan Province near the China-Myanmar-Laos border

Economic development and increased tourism in the southern region of Yunnan Province in China, adjacent to several countries in Southeast Asia, has increased the likelihood of import and export of vectors and vector-borne diseases. We report the results of surveillance of mosquitoes and mosquito-borne arboviruses along the border of China-Myanmar-Laos in 2005 and 2006, and information associating several arboviruses with infections and possibly disease in local human populations. Seventeen mosquito species representing four genera were obtained, and 14 strains of mosquito-borne viruses representing six viruses in five genera were isolated from Culex tritaeniorhynchus. In addition, IgM against Japanese encephalitis virus, Sindbis virus, Yunnan orbivirus and novel Banna virus was detected in acute-phase serum samples obtained from hospitalized patients with fever and encephalitis near the areas where the viruses were isolated. This investigation suggests that Japanese encephalitis virus, Sindbis virus, and lesser-known arboviruses circulate and may be infecting humans in the China-Myanmar-Laos border region.     

Vector competence of five common mosquito species in the People's Republic of China for Western equine encephalitis virus

Two strains of the Western equine encephalitis virus (WEEV) were first detected and isolated in China in 2001. The maintenance and transmission cycles of WEEV in China are currently not well understood, and the mosquito vectors involved in these cycles are unknown. To understand the ability of the local mosquitoes in China to transmit WEEV, the vector competence of five mosquito species, namely, Culex pipiens pallens Coquillett, Cx. p. quinquefasciatus Say, Aedes (Stegomyia) albopictus Skuse, Ae. (Stegomyia) aegypti Linnaeus, and C. tritaeniorhynchus Giles, for WEEV were evaluated. Infection rates for Cx. p. pallens, Cx. p. quinquefasciatus, Cx. tritaeniorhynchus, Ae. Albopictus, and Ae. aegypti were 46%, 60%, 80%, 37%, and 25%, respectively. Dissemination rates for the same species were 60%, 61%, 75%, 55%, and 50%, respectively. Transmission rates were 41%, 53%, 57%, and 45% for Cx. p. pallens, Cx. p. quinquefasciatus, Ae. Albopictus, and Ae. Aegypti, respectively. Infection rates were significantly different between species, but the difference between dissemination and transmission rates were nonsignificant. These results suggest that several local mosquito species in China are competent laboratory vectors for WEEV.     

Retrospective analysis of epidemiological investigation of Japanese encephalitis outbreak occurred in Rourkela, Orissa, India

There was an outbreak of Japanese encephalitis (JE) during July/August of 1993 in Rourkela City of Orissa, India. Among the serum samples, 40% of the sera showed antibodies against JE, while 17% of the sera showed recent infection to dengue virus. As many as 15 species of mosquitos were encountered in and around the affected areas. Species like Culex tritaeniorhynchus, Cx, vishnui, Cx. pseudovishnui and Cx. bitaeniorhynchus constituted 19% of the total collections. The above species were resistant to DDT and dieldrin, but susceptible to malathion.     

Mosquito surveys carried out on Green Island, Orchid Island, and Penghu Island, Taiwan, in 2003

Field surveys of mosquitoes were carried out on Green, Orchid, and Penghu Islands in 2003 to ascertain the status of mosquito vectors. Eighteen species of mosquitoes were collected, including three species of Anopheles, four species of Aedes, eight species of Culex, two species of Armigeres, and one species of Malaya. Seventeen previously recorded species were not collected in this study but 11 species collected had not previously been recorded. Ten newly recorded species, An. maculatus, An. takasagoensis, Ae. alcasidi, Ae. lineatopennis, Ae. vexans vexans, Ar. omissus, Cx. vishnui, Cx. halifaxii, Cx. hayashii, and Cx. neomimulus, were collected on Green Island and one previously unrecorded species, Ar. subalbatus, was collected on Orchid Island. Potential vectors An. maculatus and An. sinensis, malaria vectors in Korea and Mainland China, Ae. albopictus, a vector of dengue in Taiwan and West Nile virus in the USA, Cx. vishnui and Cx. tritaeniorhynchus, Japanese encephalitis vectors in Taiwan, Ae. vexans vexans, an eastern equine encephalitis vector in the USA, and Cx. quinquefasciatus, a vector of filariasis in Taiwan and West Nile virus in the USA, were among the mosquito species collected.     

Outdoor resting preference of Culex tritaeniorhynchus, the vector of Japanese encephalitis in Warangal and Karim Nagar districts, Andhra Pradesh

BACKGROUND & OBJECTIVES: Entomological investigations were carried out in Warangal and Karim Nagar districts of Andhra Pradesh during viral encephalitis outbreak in July 2003. METHODS: Adult mosquito collections in outdoor were done using sweep cage method and in indoor with the help of aspirator tube and flash light. Larval collections were done by dipping method. JE virus positivity was tested by IgM capture ELISA test. RESULTS: Outdoor collections revealed presence of Culex tritaeniorhynchus, Cx. bitaeniorhynchus and Cx. gelidus and in indoor collections--Cx. quinquefasciatus, Cx. tritaeniorhynchus, An. vagus and An. subpictus. In the outdoor collections Cx. tritaeniorhynchus was predominant (96.3% of total collection). Three samples out of 55 serum samples from human cases and five from contacts showed the presence of antibodies against JE virus. INTERPRETATION & CONCLUSION: Cx. tritaeniorhynchus, a known vector of JE is predominant in outdoors and playing a main role in JE transmission in this area. Vector control aimed at the outdoor resting population might limit virus circulation in the mosquito vertebrate host cycle and prevent human infection.