马西尼罗河病毒病的诊断方法

西尼罗河病毒病(West Nile virus disease)是一种虫媒性病毒病，其病原为西尼罗河病毒(West Nile virus)。该病毒属黄病毒科的乙型脑炎病毒血清群，可引起人类及马、鸟类出现脑炎症状，马是该病毒的终宿主。近年来，西尼罗河病毒病频繁发生于欧洲、北美洲及中东、西亚的一些国家和地区，如     

上海地区几种动物血清中西尼罗河病毒抗体的调查

西尼罗河病毒病是一种外来的新发性的虫媒人兽共患病,近年来已经成为全球公共卫生的新威胁。为了了解上海地区西尼罗河病毒在不同动物中的存在情况,采用酶联免疫吸附试验(ELISA)方法对上海市马匹、鸭、动物园珍禽进行西尼罗河病毒的血清学调查。结果显示:上述3种动物均存在不同程度的西尼罗河病毒的抗体,马、珍禽、鸭中的抗体阳性率分别达到67.5%、17.9%和23.3%。本次西尼罗河病毒抗体调查的数据和分析为制定科学、合理的防控对策提供了技术依据。     

西尼罗河热

西尼罗河热又名西奈热是由西尼罗河病毒引起的一种人畜共患病。该病1937年首次从乌干达西尼罗河流域一名发热妇女的血液中分离出，最初，人们只认为它是非洲的一种地方病，直到1957年，以色列西尼罗河病毒性脑膜炎流行后人们才认识到这种病毒的危害，60年代在法国，70年代在南非也相继发生了西尼罗河病毒感染的流行。90年代以来，感染暴发的地区明显增加：1994年在阿尔及利亚西部发生了50例有症状的西尼罗河病毒的感染，并造成8人死亡；1996年，罗马尼亚共有352人发生了西尼罗河病毒性脑膜炎；1997年捷克共和国、1998年刚果和1999年俄罗斯先后出现了西尼罗河病毒感染的流行，1999年，西尼罗河病毒传人美国，造成25人发病7人死亡的结果，此后，美国年年有西尼罗河病毒感染的病例。     

西尼罗河热流行病学及其研究概况

西尼罗河热是一种虫媒性病毒病,其病原为西尼罗河病毒,该病毒属黄病毒科、黄病毒属的单股RNA病毒,目前存在两种谱系,谱系Ⅱ株主要见于非洲;而谱系Ⅰ株分布广泛,是最近几次大爆发的病原,已确认与人类疾病有关.作者就该病的病原、流行病学、感染情况、病理变化、诊断以及预防和治疗等方面作一综述.     

马西尼罗河病毒病研究进展

自西尼罗河病毒发现以来,不断有人畜感染的报道。近年来,西尼罗河病毒病流行呈逐年上升趋势,给人类带来危害并造成畜牧业的巨大经济损失。笔者对马西尼罗河病毒的病原学、流行特征、传染情况、临床表现、诊断及疫苗的研究进行了简要综述。     

西尼罗河病毒的流行病学研究概况

西尼罗河病毒病是由西尼罗河病毒(WestNileVirus,WNV)引起的一种人畜共患病。该病毒自从1937年首次被分离以来,就被认为是存在于非洲、西亚、中东地区中能在人身上无症状存在且能引起人发热的一种病毒。1999年以前,西半球地区并无该病毒感染人或动物的记载。1999年和2000年,美国的纽约城区、新泽西州、康涅狄格州报道了在人身上爆发了西尼罗河病毒性脑炎。在这两年中,报道83个病例,其中9人死亡。2001年有10个州共报道66个病例,其中9人死亡。2002年西尼罗河病毒活动扩展到44个州,4156人感染,其中284人死亡。此病自1999年在美国纽约州爆发,…     

西尼罗河热简介

１９９９年１０月份美国在纽约州长岛病马中分离到西尼罗河热病毒,这是在美洲动物体中首次发现西尼罗河热,引起人们的关注。在１１月份以色列也报告暴发一起鹅西尼罗河热。西尼罗河热在我国比较陌生,现将有关情况作一介绍,以期对西尼罗河热有一初步了解。西尼罗河热由黄病毒科西尼罗病毒引起,该病毒与日本脑炎病毒同属一科,与美国已存在的圣路易斯脑炎病毒关系密切。与日本脑炎一样,西尼罗河热也是一种人畜共患病,对人类健康可造成严重危害,１９９６年一１９９７年罗马尼亚布加勒斯特及其附近暴发西尼罗河热,临床病例５００人,病…     

西尼罗河病及其防控方案

西尼罗河病(West Nile Disease),又称西尼罗河热(West Nile Fever)或西尼罗河脑炎(West Nile Virus Encephalitis),是由西尼罗河病毒(West Nile Virus,WNV)引起的一种急性人畜共患传染病,患病动物和病人出现类流感或脑炎症状,严重甚至导致死亡。     

西尼罗河热流行趋势与主要特征

西尼罗河热(West Nile Fever)是由西尼罗河病毒(West Nile Virus;WNV)引起的一种人兽共患的急性传染病.最早是于1937年在乌干达西尼罗河地区,从一名发热成年妇女的血液中分离到该病毒,所以称为西尼罗河病毒.     

西尼罗河病肆虐美国

西尼罗河病是由西尼罗河病毒(West NileVirus,WNV)引起的一种人畜共患的自然疫源性的虫媒传染病,在临床上可表现为症状轻微的流感样的西尼罗河热和症状严重、可导致死亡的西尼罗河脑炎(包括脑膜炎和脑膜脑炎)。该病于60年前首次爆发于乌干达,随后传播到非洲各国、欧亚大陆和中东国家,但1999年以前,西半球却从未发现。然而,自1999年8月首次爆发于美     

上海闵行地区犬和猫中西尼罗河病毒病血清学调查

西尼罗病毒病是一种外来的新发性的虫媒人兽共患病,近年来已经成为全球公共卫生的新威胁。采用ELISA对上海市闵行地区犬和猫中西尼罗河病毒的血清学调查结果显示,在所调查的7个地区中,犬和猫中的抗体阳性率分别达到4.6%和15.5%。本调查数据和分析为制定科学、合理的防控对策提供了技术依据。     

体外转录法制备西尼罗河热病毒RNA片段

目的通过体外转录获得西尼罗河热病毒保守区基因的RNA片段,为核酸快速检测方法的建立和改进提供阳性定量标准品。方法设计西尼罗河热病毒基因保守区克隆引物,PCR从合成的基因DNA获得相应片段,连接至质粒PGEM-T-easy上并筛选阳性重组质粒,测序鉴定后酶切线性化,用T7RNA聚合酶进行体外转录,得到固定长度的RNA片段,DNase酶处理后测定浓度,梯度稀释后用RT-PCR验证。结果获得含西尼罗河热病毒靶基因序列的准确定量拷贝数的RNA片段,质量浓度分别为352.6ng/μL,RT-PCR验证均扩增出相应目的条带。结论获得的RNA片段可作为西尼罗河热病毒核酸快速检测方法的阳性定量标准品。     

上海地区禽与马血清中西尼罗病毒抗体的调查

西尼罗病毒病是一种以鸟类为中间宿主、以马为终末宿主的人兽共患病,给全球公共卫生带来严重威胁。本文用ELISA方法对上海地区禽和马中西尼罗病毒的血清学进行了调查,结果显示,在所调查的2005年到2009年14类95份禽血清和7个区341份马血清中,禽和马的抗体阳性率分别为5.26%和0%。结果表明,该病在上海已通过禽类开始广泛传播,虽尚未发现终末宿主感染,但已存在一定隐患。因此,应进一步监测该病的流行与传播情况。     

West Nile virus and its emergence in the United States of America

Zoonotic West Nile virus (WNV) circulates in natural transmission cycles involving certain mosquitoes and birds, horses, humans, and a range of other vertebrates are incidental hosts. Clinical infections in humans can range in severity from uncomplicated WNV fever to fatal meningoencephalitis. Since its introduction to the Western Hemisphere in 1999, WNV had spread across North America, Central and South America and the Caribbean, although the vast majority of severe human cases have occurred in the United States of America (USA) and Canada. By 2002-2003, the WNV outbreaks have involved thousands of patients causing severe neurologic disease (meningoencephalitis and poliomyelitis-like syndrome) and hundreds of associated fatalities in USA. The purpose of this review is to present recent information on the epidemiology and pathogenicity of WNV since its emergence in North America.     

西尼罗病毒套式RT-PCR检测方法的建立

从GenBank上调取西尼罗病毒的基因序列,经过分析,设计并合成2套套式RT-PCR引物,分别对西尼罗病毒灭活苗进行扩增,结果扩增出与目的片段大小一致的条带,将其克隆入pMD18-T-Vector中,进行序列测定,证实为WNV的基因。建立了套式RT-PCR检测方法,经各反应条件的优化后,发现2套nest-PCR引物能分别扩增出85个拷贝和62个拷贝的双链DNA,对乙型脑炎病毒、黄热病毒等11种病毒核酸进行扩增,发现具有良好的特异性,显示建立套式RT-PCR具有高效、快速、特异、灵敏的特点,可用于口岸WNV的检测和监测。     

新疆地区蚊类携带西尼罗病毒情况调查研究

为查明新疆地区蚊体内携带西尼罗病毒的情况,从2005年-2007年每年的7月~10月采集新疆不同地区的蚊子共计16000余只,并提取总RNA,通过RT-nest PCR的方法检测样品中西尼罗病毒。结果表明,调查样品中没有检测到西尼罗病毒,但不能就此推测新疆是否存在西尼罗病毒,至少对新疆地区和全国制定针对不同动物和人的积极防御政策有重要的公共卫生学意义。     

Characterization of West Nile virus (WNV) isolates from Assam,India: Insights into the circulating WNV in northeastern India

West Nile virus (WNV) is a mosquito-borne flavivirus that causes subclinical symptoms, febrile illness with possible kidney infarction and encephalitis. Since WNV was first serologically detected in Assam during 2006, it has become recognized as an important etiological agent that causes acute encephalitis syndrome (AES) in addition to endemic Japanese encephalitis virus (JEV). Therefore, isolating and characterizing the currently circulating strain of WNV is important. The virus was isolated from the cerebrospinal fluid (CSF) of two patients that presented with AES. The genotyping of the isolates HQ246154 (WNIRGC07) and JQ037832 (WNIRTC08) based on the partial sequencing of 921 nucleotides (C-prM-E) of the genome placed them within lineage 5 along with other Indian strains isolated prior to 1982, but the present circulating virus formed a distinct subclade. The derived amino acid sequence alignment indicated substitution in A₈₁T and A₈₄P of the capsid region in HQ246154. A cross-neutralization assay suggested substantial antigenic variation between isolates. The pathogenesis in mice that suggested the circulating WNV was neuroinvasive and comparatively more pathogenic than previous strains from India.     

Equine encephalomyelitis outbreak caused by a genetic lineage 2 West Nile virus in Hungary

Background: The spread of lineage 2 West Nile virus (WNV) from sub‐Saharan regions to Europe and the unpredictable change in pathogenicity indicate a potential public and veterinary health threat and requires scientific awareness. Objectives: To describe the results of clinical and virological investigations of the 1st outbreak of a genetic lineage 2 WNV encephalomyelitis in horses. Animals: Seventeen horses with neurologic signs. Methods: Information regarding signalment, clinical signs, and outcome was obtained for each animal. Serology was performed in 15 cases, clinicopathological examination in 7 cases, and cerebrospinal fluid was collected from 2 horses. Histopathology was carried out in 4 horses, 2 of which were assessed for the presence of WNV in their nervous system. Results: WNV neutralizing antibody titers were between 10 and 270 (median, 90) and the results of other serological assays were in agreement with those of the plaque reduction neutralization test. Common signs included ataxia, weakness, asymmetric gait, muscle tremors, hypersensitivity, cranial nerve deficits, and recumbency. Twelve animals survived. Amplicons derived from the infection‐positive specimens allowed molecular characterization of the viral strain. Conclusions and Clinical Importance: From our results, we conclude that this outbreak was caused by a lineage 2 WNV strain, even though such strains often are considered nonpathogenic. Neurological signs and survival rates were similar to those reported for lineage 1 virus infections. The disease occurrence was not geographically limited as had been the typical case during European outbreaks; this report describes a substantial northwestern spread of the pathogen.     

Experimental studies of the role of the little raven (Corvus mellori) in surveillance for West Nile virus in Australia

Objective To study the potential role of an Australian corvid, the little raven (Corvus mellori), in the surveillance for exotic West Nile virus (WNV) in Australia. Method In a series of trials, little ravens were infected with WNV (strain 4132 New York 1999) and Kunjin virus (strain K42886) by the intramuscular route. They were observed for 20 days during which blood and swab samples were taken for virus isolation. Tissue samples were taken from ravens humanely killed during the acute infection period, and at the termination of the trials, for virus isolation, histopathology and immunohistochemistry. Results Ravens infected with WNV became mildly ill, but all recovered and seroconverted. Blood virus titres peaked around 3 to 4 days after inoculation at levels between 10^3.0 to 10^7.5 plaque forming units/mL. Virus or viral antigen was detected in spleen, liver, lung, kidney, intestine, testis and ovary by virus isolation and/or immunohistochemistry. WNV was detected in oral and cloacal swabs from 2 to 7 days post inoculation. The molecular and pathogenic characteristics of the inocula were consistent with them being of high virulence, as expected for this isolate. Ravens infected with Kunjin virus developed viraemia and seroconverted, although they did not develop disease. Conclusions Little ravens do not develop severe disease in response to virulent WNV infection and for this reason may not be important sentinel hosts in the event of an outbreak of WNV, as in North America. However, as they have relatively high viraemias, they may be able to support virus cycles.