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37编辑同志:人的乙型脑炎与猪的乙型脑炎有关系吗?怎样预防猪的日本乙型脑炎?(项群)项群同志:日本乙型脑炎又称流行性乙型脑炎,是由日本乙型脑炎病毒引起的,由蚊子传播的一种人畜共患病。夏秋季节流行。猪感染后表现为流产、死胎和睾丸炎等繁殖障碍症状。猪是最主要的乙脑病毒宿主,蚊子叮咬患猪后再叮人,就可能把乙脑病毒传染到人体,引起人患乙型脑炎。所以,搞好猪乙型脑炎防制,不仅对养猪生产而且对公共卫生有重要意义。病原特点日本乙型脑炎病毒(JEV)为黄病毒科、黄病毒属(Flavivirus)成员,又名流行性乙型脑炎病毒。病毒粒子呈球形,直径…     

一起猪乙型脑炎疫病的诊制报告

猪日本乙型脑炎义称流行性乙型脑炎,是由日本脑炎病毒引起的一种急性、人兽共患虫媒传染病。乙型脑炎对人类（特别是儿童）的中枢神经系统危害巨大。猪是乙脑的重要传染源和储存宿主,通常乙脑病毒的感染呈现猪．蚊．人链状条。乙脑也是导致种猪繁殖障碍的重要元凶之一,病猪主要表现妊娠母猪流产、产死胎,公猪睾丸肿大,少数猪有神经症状。     

家畜传染病学分会第十三次学术研讨会学术报告之四 近年来我国流行性乙型脑炎研究进展

流行性乙型脑炎又称日本乙型脑炎,简称乙脑,是由日本乙型脑炎病毒(Japanese encephalitis Virus,JEV)引起的一种蚊媒性人兽共患传染病。多种动物易感,蚊是JEV的主要传播媒介,猪是该病毒在自然界最重要的贮存和增殖宿主,且可引起仔猪脑炎和种猪繁殖障碍,给养猪业造成巨大经济损失。人对JEV普遍易感,但大多数为隐性感染,少数青少年及儿童感染后发生病毒性脑炎,病死率高。     

近年来我国流行性乙型脑炎研究进展

流行性乙型脑炎又称日本乙型脑炎,简称乙脑,是由日本乙型脑炎病毒（Japanese encephalitis Virus,JEV）引起的一种蚊媒性人兽共患传染病。多种动物易感,蚊是JEV的主要传播媒介,猪是该病毒在自然界最重要的贮存和增殖宿主,且可引起仔猪脑炎和种猪繁殖障碍,给养猪业造成巨大经济损失。人对JEV普遍易感,但大多数为隐性感染,少数青少年及儿童感染后发生病毒性脑炎,病死率高。     

猪流行性乙型脑炎综合防治

流行性乙型脑炎是由乙型脑炎病毒(JEV)引起的一种人畜共患病。本病多发于7~10月的蚊虫滋生、活动旺季,猪是该病毒的主要增殖宿主、扩散宿主和传染源。易感季节管理不善的猪群该病感染率极高,是夏秋季猪场的主要流行病,常呈散发性或地方性流行。1流行病学流行性乙型脑炎属自然疫源性疫病。JEV于上世纪50年代首先在日本分离获得,因此又称日本脑炎病毒。为与甲型脑炎区别,该病定名为流行性乙型脑炎,简称乙脑。     

猪乙型脑炎疫苗免疫试验

<正>乙型脑炎(Japanese encephalitis,JE)又称日本乙型脑炎、流行性乙型脑炎,俗称乙脑,是由流行性乙型脑炎病毒(Japanese encephalitis virus,JEV)引起的一种人畜共患传染病~([1]),也是导致猪繁殖障碍的主要疾病之一。蚊虫是该病的传播媒介,呈明显的季节性流行。猪是该病的扩散宿主,乙型脑炎病毒可通过蚊虫叮咬传染给人。猪感染本病后,母猪主要表现为死胎,公猪主要表现为急性睾丸炎,肥育     

猪乙型脑炎的诊断与综合防控

猪日本乙型脑炎又名流行性乙型脑炎，是由猪日本乙型脑炎病毒引起急性的人、兽共患传染病。病毒对热和日光的抵抗力不强，常用来苏儿和石炭酸，均可在数分钟内将其杀死。乙型脑炎危害较大，可感染多种动物和人，对猪危害最为严重。     

猪流行性乙型脑炎的防控

正猪流行性乙型脑炎,最早发生在日本,又称日本乙型脑炎。猪流行性乙型脑炎是由流行性乙型脑炎病毒引起的猪的一种急性、热性传染病。猪流行性乙型脑炎病毒与人的病毒无差异,是人兽共患的传染病。马、牛、羊、猪、禽类及人等均可感染。在人,称脑炎或脑膜炎,但很少死亡。该病的特征是猪被感染后,大多数不显症状,主要表现为高热、流产、早产、死胎,公猪发生睾丸炎,表现为睾丸肿胀。常用的实验室诊断方法有:血凝抑制试验、中和试验和补体结合试验等。在诊断     

猪乙型脑炎的综合防制

猪日本乙型脑炎又名流行性乙型脑炎,是由猪日本乙型脑炎病毒引起的急性人兽共患传染病.病毒对热和日光的抵抗力不强,常用消毒药来苏儿和石炭酸,均可在数分钟内将其杀死.乙型脑炎危害较大,可感染多种动物和人,对猪危害最为严重.     

猪乙型脑炎病的诊断与防控

猪乙型脑炎是一种人畜共患病,是由乙型脑炎病毒引起的一种急性、发热性传染病,猪是本病最重要的传染源和储存宿主。2021年7月,某养猪场发生了以母猪流产和公猪睾丸炎为主要发病特征的传染病,通过在养猪场开展流行病学调查,观察临床发病症状和剖检病理变化,结合实验室病原PCR检测、病毒分离培养、病毒含量测定、病毒中和等试验方法,确诊该养殖场感染猪乙型脑炎病毒造成发病。该养猪场通过采取加强饲养管理和疫苗紧急免疫接种等综合防控措施,取得了很好的防控效果。     

猪日本脑炎病毒NS3基因实时RT-LAMP快速检测方法的建立

建立日本脑炎病毒一步法实时环介导逆转录等温快速扩增方法.根据日本脑炎病毒序列保守的非结构区基因NS3设计4条特异引物,用于扩增SA14-14-2株、SA103株和GD06株日本脑炎病毒获得成功,在病毒感染的单层细胞和猪体内都可以检出病毒.与常规SYBR GreenI适时荧光RT-PCR方法比较和Ct值分析,用不同稀释度病毒RNA,两者敏感性相似,适时RT-PCR在模板浓度低时结果更稳定.FIP和BIP纯度会影响反应效果,反应时间和模板浓度会影响电泳条带.一般63 ℃~65 ℃ 30 min可出现结果,模板浓度低时要适当延长反应时间.以SYBR GreenI为指示剂,RT-LAMP在63 ℃~65 ℃循环扩增检测日本脑炎病毒,1.5 min/循环,30个循环,Ct值为21.5.提示RT-LAMP方法用于日本脑炎诊断、鉴别,是敏感、可靠、成本低廉的方法,有助于人畜日本脑炎的防控工作.     

猪日本脑炎DNA疫苗的构建与鉴定

为开发猪日本脑炎新型疫苗,采用PCR方法扩增日本脑炎病毒WHe株prME和NS1基因,并将其分别克隆至DNA疫苗载体pVAX1,分别用酶切和测序分析进行鉴定。结果表明prME和NS1基因大小分别为2.1kb和1.1kb,酶切和测序结果表明,猪日本脑炎DNA疫苗pVAX1-prME和pVAX1-NS1构建成功,为进一步免疫试验奠定了基础。     

猪乙型脑炎疫苗研究进展

猪乙型脑炎（Japanese encephalitis，JE）是由乙型脑炎病毒（JEV）引起的一种经蚊虫传播的人畜共患病，且是严重威胁人畜健康的一种中枢神经系统的急性传染病。猪是JEV的重要储存宿主和扩增宿主，同时也是乙型脑炎的主要传染源，可引起母猪繁殖障碍和公猪睾丸炎。人是JEV的终末宿主，特别是儿童，感染发病后，死亡率可达25%。目前，仍无有效药物治疗乙型脑炎感染，而其流行区域的扩大及其优势基因型的改变为JEV防控策略带来了新的挑战。近年来，随着基因工程和蛋白质工程的发展，以及对病毒分子结构和功能的深入研究，一些新技术新手段被应用到JEV疫苗研发中，基因工程亚单位疫苗、病毒样颗粒疫苗、嵌合病毒减毒活疫苗、多表位疫苗、DNA疫苗等应运而生。在疫苗制备过程中，培养工艺的优化、病毒抗原的纯化、新型佐剂和耐热保护剂的应用等生产工艺的提升策略，为保障JEV疫苗的质量提供了新方向。文章简述了猪JEV疫苗的使用现状及研发进展，旨在为研制更安全、有效的猪JEV疫苗提供参考依据。     

乙脑病毒非结构蛋白NS1的原核表达及重组蛋白间接ELISA方法的初步建立

克隆表达乙脑病毒非结构蛋白NS1,并以其作为包被抗原,建立间接ELISA诊断方法。用此方法分别检测猪繁殖与呼吸综合征病毒(PRRSV)、猪瘟病毒(CSFV)及猪圆环病毒(PCV)阳性血清各3份,以及33份健康非免疫仔猪血清和205份乙型脑炎灭活疫苗免疫的猪血清,评价NS1-ELISA方法的特异性。取54份乙脑病毒感染的猪血清进行NS1-ELISA检测,评价该方法的敏感性。NS1-ELISA检测的特异性为95%,敏感性达90.7%。与商品化试剂盒比较,其符合率达到96.0%。在重复性试验中,NS1-ELISA检测方法重复性较好。本试验为进一步研究不同感染时期NS1抗体水平的差异奠定基础。     

The seroprevalence of Japanese encephalitis virus in goats raised in Korea

Japanese encephalitis virus (JEV) causes a mosquito-borne viral zoonosis that is becoming increasingly important to public health in east and south Asia. Although JEV is primarily associated with reproductive failure in swine, JEV infection can cause fever and headache in humans and is associated with aseptic meningitis and encephalitis. The exact mode of transmission, including host range and possible source of viral amplification within livestock, is still not completely clear. This study consisted of a serological survey of JEV infection in goats. A total of 804 goat serum samples were collected from 144 farms in Korea between May 2005 and May 2006. The incidence of positive cases was 12.1% (97 out of 804 goats). The seroprevalence of JEV infection in the 144 farms screened was 31.3% (45/144), indicating that JEV infection is frequent in goat farms in Korea. In addition, three districts of Korea (mainly in the southern region) had a higher seroprevalence of JEV compared to other areas. The results suggest that goats could be monitored epidemiologically as a sentinel animal for JEV transmission in Korea.     

Japanese encephalitis virus immunoglobulin M antibodies in porcine sera

A solid-phase enzyme-linked immunosorbent assay (ELISA) was developed for detection of porcine immunoglobulin (Ig)M antibodies to Japanese encephalitis virus (JEV). Antibodies in sera were captured onto the solid phase of Microtiter plates sensitized with mouse monoclonal antibodies to porcine mu heavy chain. Virus antigen binding to the lawn of IgM was quantitated by subsequent binding of peroxidase-labeled human hyperimmune anti-JEV IgG, which in the final step, catalyzed a substrate color change. In sucrose density-gradient fractionated sera from recently infected pigs, the peak of ELISA JEV IgM activity corresponded to the peak of 18-S, 2-mercaptoethanol-sensitive hemagglutination-inhibiting (HAI) antibody activity. Within 2 to 3 days, JEV-infected sentinel pigs developed high JEV IgM activity; this activity decreased within 2 weeks. Among specimens collected from 99 random swine at abattoirs in Thailand during a period of low JEV transmission, none of 25 JEV HAI-negative sera had JEV IgM activity, 7 of 74 JEV HAI-positive sera did have JEV IgM activity, and the remaining 67 sera had readily detectable JEV HAI antibodies, but lacked JEV IgM. The JEV IgM solid-phase ELISA was useful for rapidly diagnosing active or recent JEV infections in swine.     

乙型脑炎疫苗研发及应用研究进展

乙型脑炎是由日本脑炎病毒引起的一种人兽共患的蚊媒传染病,它对人类危害巨大,并且给养猪业造成了严重的经济损失,目前临床上还无有效的药物用于治疗该病,而接种乙型脑炎疫苗能有效预防该疫病的流行。自乙型脑炎病毒疫苗应用以来,乙型脑炎的发病率大大下降。论文介绍了乙型脑炎疫苗的发展过程及生产工艺技术,总结了灭活疫苗、减毒活疫苗以及嵌合减毒活疫苗的免疫效果、优势和不足,最后探讨了当前乙型脑炎疫苗可能存在的安全问题以及新型乙型脑炎疫苗的发展方向,以期为新型乙型脑炎疫苗的研发提供参考,为乙型脑炎的防控提供新的思路与科学依据。     

日本脑炎病毒套式RT-PCR方法的建立与初步应用

根据GenBank上登录的日本脑炎病毒(JEV)E基因序列,设计内外2对引物.以JEV疫苗株为模板,建立了检测猪JEV的套式RT-PCR方法.应用该方法对JEV疫苗株RNA进行扩增,获得与预期大小相符,长度为228 bp的目的片段;检出JEV-RNA的灵敏度约为0.3 pg.表明所建立的套式RT-PCR方法对JEV的检测敏感性高、特异性强.     

Quantitative and Qualitative Study of Enzyme-linked Immunosorbent Assay to Detect IgG against Japanese Encephalitis Virus in Swine Sera

This study was designed to investigate the application of indirect enzyme-linked immunoassay (ELISA) in detecting IgG against Japanese encephalitis virus in swine sera and the qualitative nature of this test. The attenuated strain SA14-14-2 of Japanese encephalitis virus (JEV) was inoculated into 9-day-old chicken embryos and virus was harvested, purified and suspended in 0.9% saline as JEV antigen. The control antigen was prepared by the same method as for the antigen. In the ELISA, the optimal concentrations of antigen coated and dilution factor were selected using chi2 test. Ninety-two swine sera negative to haemagglutination inhibition (HI) were tested by this assay and the positive threshold was determined. The results of this study indicate that indirect ELISA has high specificity, sensitivity and reproducability. Simultaneous testing of 74 serum samples from nine pig farms was carried out to compare the existing HI test and the indirect ELISA. The coincidence rate of the two assays was 85.1% (63/74) and no significant difference was observed between them (p > 0.05). This ELISA test can detect 46 swine serum samples qualitatively and the titre of eight swine serum samples through endpoint dilution quantitatively within one 96-well plate.     

Sero-survey on Aino, Akabane, Chuzan, bovine ephemeral fever and Japanese encephalitis virus of cattle and swine in Korea

Vector-borne arboviruses produce mild to severe symptoms in domestic animals. Bovine ephemeral fever (BEF), Akabane, Aino, and Chuzan virus have been primarily attributed to reproductive disorders or febrile diseases in cattle, and Japanese encephalitis virus (JEV) is mainly associated with reproductive failures in swine. We investigated antibody titers from domestic swine against four bovine arboviruses (BEF, Akabane, Aino, and Chuzan virus) and from cattle against JEV in Korea. While the positive rates for Akabane and BEF were 37.4% and 15.7%, the positive incidence of Chuzan and Aino were relatively low, with positive rates of 3.04% and 0.4%, respectively, based on a virus neutralization assay. Antibody titers against more than one virus were also frequently detected in domestic swine. The incidence of JEV was 51.3% among domestic cattle. In addition, one positive case was detected in the thoracic fluids from 35 aborted calves, based on the hemagglutination inhibition test. Our results indicate that swine are susceptible hosts of bovine arboviruses without showing clinical symptoms in a natural environment. Moreover, we confirmed that JEV could be associated with reproductive failure in pregnant cattle, as were other vector-borne bovine arboviruses assessed in this study.