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1.
试验旨在了解珠江上游地区乙型脑炎病毒(JEV)主要传播媒介蚊虫的种类、分布及携带JEV基因型和分子特征。2013年7月在珠江上游地区师宗县采集蚊虫和库蠓标本,并对蚊虫进行分类鉴定;同时采用黄病毒属引物对采集到的蚊虫和库蠓标本进行检测,阳性标本用JEV PrM和E基因特异引物进行扩增、测序,然后采用生物信息学软件进行序列分析。在4个采集点共采集蚊虫3 705只,分别属于库蚊、按蚊、伊蚊和阿蚊4个属的7种蚊虫,牛圈以中华按蚊、骚扰阿蚊为优势蚊种,羊圈以中华按蚊、骚扰阿蚊为优势蚊种,猪圈以三带喙库蚊、中华按蚊和骚扰阿蚊为优势蚊种。采用JEV PrM和E基因特异引物对采集到蚊虫和库蠓标本分162批进行扩增、测序,采用生物信息学软件进行序列分析。结果显示,4株蚊虫携带的病毒均为基因Ⅰ型JEV,与疫苗株SA14-14-2E蛋白存在15个氨基酸差异位点,在8个影响病毒毒力的重要位点上未发生突变。以上结果提示珠江上游地区存在多种蚊虫种类,三带喙库蚊和中华按蚊是该地区的优势蚊种,三带喙库蚊是当地JEV的主要传播媒介,在当地的媒介中存在基因Ⅰ型JEV流行,而流行株的毒力并未降低。  相似文献   

2.
阿卡斑(赤羽病)病毒的分离与初步鉴定   总被引:5,自引:0,他引:5  
1998年7月~8月从上海地区采集的蚊、蠓等标本中分离到12株病毒,其中有3株电镜观察病毒近似球囊膜、病毒对乙醚、氯仿和胰蛋白酶敏感,对酸、热不敏感,抵抗5-氟脱氧尿苷。经血清-细胞和动物中和试验鉴定,该三株病毒均能被AKV病毒高效价免疫血清中和,其余9株病毒未被AKV高价免疫血清中和,经初步鉴定证实上述三株病毒为阿卡斑病毒(Akabane virus,AKV)。阿卡斑病毒在我国的分离尚属首次报道  相似文献   

3.
在我国吉林省某地猪生殖呼吸道综合征病毒(PRRSV)抗体阳性猪群的4头2日龄弱仔猪实质脏器中分离到2株PRRSV,间接荧光抗体试验(IFA)结果表明,PRRSV(LV.VR-2332)抗血清与2个分离株呈阳性反应;分离到病毒的弱仔猪血清与参考株(LV.VR-2332)也呈阳性反应,而分离株与HCV,PrV,PPV,TGEV,PEDV和HEV无交叉抗原,以上试验证明,我们已成功地分离到2株地方性PR  相似文献   

4.
在我国吉林省某地猪生殖-呼吸道综合征病毒(PRRSV)抗体阳性猪群的4头2日龄弱仔猪实质脏器中分离到2株PRRSV。间接荧光抗体试验(IFA)结果表明,PRRSV(LV.VR-2332)抗血清与2个分离株呈阳性反应;分离到病毒的弱仔猪血清与参考株(LV.VR-2332)也呈阳性反应;而分离株与HCV、PrV、PPV、TGEV、PEDV和HEV无交叉抗原。以上试验证明,我们已成功地分离到2株地方性PRRSV。进一步用六种PRRSV单抗(A~F)进行IFA试验,结果2个分离株与VR-2332的荧光反应谱相同。说明它们之间在抗原结构上具有同源性。  相似文献   

5.
从5份粪样(3份采自腹泻猪,2份采自3月龄临床健康猪)分离到呼肠病毒,命名为OS-324通过交叉中和试验确定这些分离株的血清型为Ⅱ型呼肠病毒,血球凝集试验结果表明,这些分离株不同于其他呼肠病毒,呼肠病毒中和抗体调查揭示,Ⅱ型呼肠病毒广泛流行于冈山地区的猪群,本文是从猪分离到Ⅱ型呼肠病毒的首篇报告。  相似文献   

6.
北京地区某猪场猪群疑似感染猪捷申病毒(porcine teschovirus,PTV),为了分离与鉴定该病毒,从采集的脑组织样品中分离出病毒,并从病毒中提取总RNA,根据已报道的引物序列,经RT-PCR扩增得到部分编码主要结构蛋白的VP1基因和高度保守的5'-UTR区基因序列,将这些基因克隆到pEASY-Blunt载体中,经序列测定,与GenBank上的毒株序列进行比对。试验结果表明,分离的毒株与猪捷申病毒同源性为95%~100%。本试验成功分离获得一株猪捷申病毒北京地方流行毒株,命名为 10BJ02株。  相似文献   

7.
从海南省蝙蝠脑中分离出1株罗斯河病毒及其血清抗体调查   总被引:18,自引:0,他引:18  
1993年,从海南省三亚市立才山区捕获的37组蝙蝠脑组织中分离到1株病毒,编号为HBb17。经理化、生物学性状及血清学鉴定,证实为罗斯河病毒(Rossrivervirus,RRV)。实验感染,该病毒能在蚊体内复制,并通过蚊媒传播。用IFA检测当地健康人、发热待查病人和鼠血清中的RRV抗体,阳性率分别为1.02%(1/98)、8.70%(4/46)和8.00%(6/75)。以上结果表明,HBb17病毒是披膜病毒科甲病毒属罗斯河病毒,在当地感染人和鼠较为广泛  相似文献   

8.
本文从自然感染绵羊慢病毒的绵羊的外周白细胞及组织中分离病毒,在接种后2代均出现细胞病变效应,将病毒培养液浓缩100倍作为抗原进行琼扩检测呈阳性反应,病毒培养液经免疫电镜检测,观察到了病毒颗粒。病毒的半数感染量约为10-5/ml,将分离到的3株OPPV分别命名为NXJ-55,NXJ-73,NXJ-0481。  相似文献   

9.
为了解上海市蚊源盖塔病毒(GETV)的分子特征,2018年7月从上海市浦东新区和奉贤区马场采集蚊媒6 000余只,接种BHK-21和C6/36细胞进行病毒分离,疑似阳性分离物采用RT-PCR和IFA技术对分离株进行鉴定。结果表明,分离到2株盖塔病毒,命名为SH201801、SH201802,分别源自中华按蚊、三带喙库蚊。对2株GETV的E2基因进行克隆测序及进化分析,结果表明,本次分离的2株GETV均属于GroupⅢ型,与M1、SH05-6、SH05-16等国内分离株同源性较高,但与马来西亚原始毒株MM2021亲缘关系较远。本研究为GETV感染的流行病学调查提供了科学依据,对上海市蚊虫及蚊媒病的防治具有重要意义。  相似文献   

10.
北京市猪乙型脑炎血清流行病学调查   总被引:3,自引:0,他引:3  
猪日本乙型脑炎(JE)属于虫媒、人兽共患病毒病,传播媒介以库蚊为主,具有明显的季节性,发病率与库蚊的消长规律有关,猪是该病毒的主要储存宿主,通过蚊叮咬传播给人.  相似文献   

11.
蝙蝠作为流行性乙型脑炎病毒宿主的研究   总被引:5,自引:0,他引:5  
1986、1988、1990和1997年的7-8月,在云南省共捕获653只蝙蝠,其中棕果蝠(Rousettus leschenaulti)593只,金管鼻蝠(Murina aurata)60只,采集血清及剖取脑组织作病毒分离和抗体检查。用细胞法和乳鼠法分离到6株病毒,带毒率为0.96%,其中从捕自景洪的棕果蝠脑组织中分离到3株,从河口的棕果蝠血清中分离到2株,从捕自耿马的金管鼻蝠脑组织中分离出1株。棕果蝠和金管鼻蝠的带毒率分别为0.84%和1.67%。这6株病毒能引起C6/36和BHK21细胞病变和导致乳小白鼠或3-4周龄小白鼠发病和死亡,并具有典型的嗜神经病毒感染症状,经血凝抑制,补体结合,免疫荧光和中和试验鉴定。新分离的6株病毒均为乙脑病毒(JE virus)。同期用血凝抑制试验对采获的425份棕果蝠血清作乙脑病毒抗体检查。阳性153-份,阳性率为36%,人有较高的感染率,。本次从棕果蝠和金管鼻蝠体内分离出乙脑病毒属具有重要流行病学意义。  相似文献   

12.
A study was conducted during 1985 and 1986 to evaluate the roles of mosquito species as possible vectors of Japanese encephalitis (JE) virus in Hokkaido. The number of Culex tritaeniorhynchus was very low among the four pig farms where outbreaks of abortion caused by JE virus were observed in swine populations. At one farm near Sapporo, only one Cx. tritaeniorhynchus was found among a total of 510 mosquitoes collected during the survey period from July to October 1985, even when JE virus activity among sentinel pigs was revealed by seroconversion. At another farm in the south, no individuals of this mosquito species were found among 987 mosquitoes collected at the time of the outbreaks of abortion. Cx. pipiens pallens, Anopheles species, Aedes vexans nipponii, and Ae. japonicus were predominant over Cx. tritaeniorhynchus. Cx. tritaeniorhynchus, almost a solve vector species of JE virus in the southern part of Japan, is probably not a vector of the virus in Hokkaido. The collected mosquitoes (2,332 from 1985 and 1,403 from 1986) were processed for virus isolation but no JE virus was isolated. More extensive field studies are necessary to provide further information on the role of mosquito species other than Cx. tritaeniorhynchus in the transmission of JE virus in the northern limits of its range including Hokkaido.  相似文献   

13.
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15.
Akabane virus was isolated from the biting midge, Culicoides oxystoma, collected in a cowshed in Kagoshima on Kyushu Island of Japan. This is the first report on the isolation of Akabane virus from biting midges of the genus Culicoides in Japan. Two calves kept as bait in the cowshed seroconverted to Akabane virus. These results strongly suggest that C. oxystoma may be a vector of Akabane virus.  相似文献   

16.
OBJECTIVE: To determine the cause of an epidemic of blindness in kangaroos. DESIGN AND PROCEDURES: Laboratory examinations were made of eyes and brains of a large number of kangaroos using serological, virological, histopathological, electron microscopical, immunohistochemical methods, and PCR with cDNA sequencing. In addition, potential insect viral vectors identified during the disease outbreak were examined for specific viral genomic sequences. SAMPLE POPULATION: For histopathological analysis, 55 apparently blind and 18 apparently normal wild kangaroos and wallabies were obtained from New South Wales, Victoria, South Australia, and Western Australia. A total of 437 wild kangaroos and wallabies (including 23 animals with apparent blindness) were examined serologically. RESULTS: Orbiviruses of the Wallal and Warrego serogroups were isolated from kangaroos affected with blindness in a major epidemic in south-eastern Australia in 1994 and 1995 and extending to Western Australia in 1995/96. Histopathological examinations showed severe degeneration and inflammation in the eyes, and mild inflammation in the brains. In affected retinas, Wallal virus antigen was detected by immunohistochemical analysis and orbiviruses were seen in electron microscopy. There was serological variation in the newly isolated Wallal virus from archival Wallal virus that had been isolated in northern Australia. There were also variations of up to 20% in genotype sequence from the reference archival virus. Polymerase chain reactions showed that Wallal virus was present during the epidemic in three species of midges, Culicoides austropalpalis, C dycei and C marksi. Wallal virus nucleic acid was also detected by PCR in a paraffin-embedded retina taken from a blind kangaroo in 1975. CONCLUSION: Wallal virus and perhaps also Warrego virus are the cause of the outbreak of blindness in kangaroos. Other viruses may also be involved, but the evidence in this paper indicates a variant of Wallal virus, an orbivirus transmitted by midges, has the strongest aetiological association, and immunohistochemical analysis implicates it as the most damaging factor in the affected eyes.  相似文献   

17.
Between July and September 2002 there were outbreaks of bluetongue on three sheep holdings in the communities of San Gregorio Magno (Salerno, Campania), Laviano (Salerno, Campania) and Carpino (Foggia, Puglia), and the involvement of bluetongue virus (btv) was confirmed serologically and virologically. The mortality rate was at least 11 per cent and involved btv serotype 2 (btv-2) and serotype 9 (btv-9). These holdings were also surveyed for the Culicoides (Diptera: Ceratopogonidae) vectors; approximately 10,000 midges belonging to 15 species were captured, but they did not include a single specimen of the classical Afro-Asiatic bluetongue vector, Culicoides imicola. Species belonging to the Obsoletus complex dominated the light-trap collections, and Culicoides obsoletus Meigen, Culicoides scoticus Downes and Kettle and Culicoides dewulfi Goetghebuer constituted 90 per cent of all the Culicoides species captured. Fifty-six pools of the Obsoletus complex (excluding C dewulfi), each containing 100 individual midges and containing only parous and gravid females, were assayed for virus. btv-2 was isolated from three pools from San Gregorio Magno and Carpino, and btv-9 was isolated from one pool from Laviano. These results indicate that a species other than C imicola is involved in the current re-emergence of bluetongue in the Mediterranean Basin, but whether it is C obsoletus sensu stricto or C scoticus, or both, is uncertain.  相似文献   

18.
Culicoides obsoletus (Diptera: Ceratopogondae) is considered as the probable main vector of Bluetongue virus (BTV) in northern Europe. Its breeding sites are poorly documented at the present time. We report numerous emergences of C. obsoletus s. str. from soil samples collected in two holdings between August and September 2010. Specimens were collected regularly in the laboratory during 80 days. In one holding, 1584 C. obsoletus midges emerged from used litter collected inside a dairy cow building and 211 C. obsoletus midges emerged from manure left outside the farm buildings. In the second holding, the number of emergences observed was much lower, especially for indoor samples. We discuss the impact of the farming practices on the abundance of emergence between both holdings on one side and between indoor and outdoor breeding sites on the other side. The observation of a peak in emergence and high emergence rates recorded in the laboratory for indoor samples let us assume that these breeding sites are of great importance, especially when it comes to understand the biology of this widespread species and its role in the transmission of BTV.  相似文献   

19.
On four nights in June 2008, light traps were operated for Culicoides biting midges, the vector species for bluetongue virus (BTV), at five sites in Chester Zoo in north-west England. Over 35,000 Culicoides midges, of 25 species, were captured, including high densities inside animal enclosures. Over 94 per cent of all the Culicoides trapped were females of the Obsoletus group, which is implicated as the vector of BTV serotype 8 in northern Europe. The mean catch of this group per trap per night was over 1500, suggesting a potential risk of BTV transmission if the virus is introduced to Chester Zoo in the animals or midges in the summer.  相似文献   

20.
Due to the probable role played by rodents as a reservoir for the transmission of the EMC virus to pigs, the experiment reported here was performed in order to assess the transmission rate of EMCV within a rat population. Twenty-five eight-week-old Wistar rats housed in individual plastic cages were experimentally infected either with a Greek myocardial EMCV strain (5 rats with a 0.2 x 10(6) TCID50 dose per rat and 10 rats with a 0.5 x 10(4.5) TCID50 dose per rat, oronasally) or a Belgian myocardial EMCV strain (10 rats with a 0.5 x 10(4.5) TCID50 dose per rat, oronasally). Two to five days later, each inoculated rat was moved to a new clean cage and coupled with a contact rat to compare the pathogenicity of the two strains and to estimate the basic reproduction ratio R0, indicating the level of EMCV transmission. During the experiments, faecal virus excretion was measured as well as the serological response against EMCV. After euthanasia, virus isolation was attempted from different rat tissues. Neither strains produced mortality, nor clinical signs and only low titres of neutralising antibodies were found. All contact rats, however, were infected and the virus was isolated from their faeces and from various tissues. Both 10-pair experiments revealed a point estimate for the R0 of infinity (95%-CI for both the Greek and Belgian EMCV strains = 4.48 - infinity), as did the 5-pair experiment with a higher dose of the Greek strain (95%-CI = 1.83 - infinity). Combining the results from the two 10-pair experiments resulted in an estimate for R0 of infinity (95%-CI: 9.87 - infinity). These results indicate that the EMC virus can spread very easily within a rat population by horizontal rat-to-rat transmission (R0 > 1).  相似文献   

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