甘肃省庆阳市媒介蚊虫类携带病毒调查

目的了解甘肃省庆阳市区域媒介蚊虫类分布特点及携带病毒情况,为防控虫媒病毒相关疾病提供科学依据。方法采用电子诱蚊灯、捕虫网诱捕,并进行分类;用细胞培养法分离病毒,用血清学分子生物学方法进行病毒鉴定。结果2012年捕获蚊虫5种,4238只,其中淡色库蚊2459只,占58．0％;中华按蚊794只,占18．73％;三带喙库蚊652只,占15．38％;刺扰伊蚊215只,占5．08％;济南按蚊118只,占2．8％;捕获的三带喙库蚊中分离出1株盖塔病毒,淡色库蚊检出6株库蚊黄病毒。结论淡色库蚊是庆阳市区域的优势蚊种,蚊虫携带黄病毒和盖塔病毒等虫媒病毒,应加大对该地区蚊虫及虫媒病毒的监测、调查、研究及防治工作。     

福建虫媒病毒研究概况

虫媒病毒（Arbovirus）由吸血昆虫（蚊、蜱、虻、蠓、蛉等）通过叮咬将病毒传播给人与动物,病毒在媒介体内繁殖、传代,引发人兽共患病。此类疾病常表现为发热、皮疹、出血和脑炎,侵犯皮肤、神经系统较多见。虫媒病毒引起的人兽共患病种类较多,近年备受关注。1950年全球仅发现35种虫媒病毒,2006年达538种。其中130余种可引起人兽共患病（主要为披膜病毒科、黄病毒科和布尼亚病毒科）,导致发热、皮疹和关节痛、出血热、休克等,严重者可致死;     

2019—2020年哈密市蚊虫种类分布及携带病毒调查

目的　了解新疆维吾尔自治区哈密市蚊虫种类及病毒携带情况,并鉴定该市尖音库蚊所属亚种。方法　分别于2019、2020年7月中旬,在新疆维吾尔自治区哈密市伊州区、伊吾县、巴里坤县采用诱蚊灯法捕捉蚊虫,鉴定所捕获蚊虫种属及尖音库蚊种属。采用逆转录PCR技术检测捕获蚊虫携带黄病毒属、甲病毒属、布尼亚病毒属、流行性乙型脑炎病毒、辽宁病毒、Tahyna病毒、蜱传脑炎病毒及西尼罗病毒情况。结果　在哈密市伊州区、伊吾县、巴里坤县共捕获蚊虫1 496只,分属于3属3种。尖音库蚊为优势蚊种,占所捕获蚊虫总数的65.91%（986只）;其次为里海伊蚊,占30.55%（457只）;阿拉斯加脉毛蚊最少,仅占3.54%（53只）。所捕获尖音库蚊经雄蚊尾器鉴定为尖音库蚊指名亚种。经逆转录PCR法检测,所捕获蚊虫黄病毒属、甲病毒属、布尼亚病毒属、流行性乙型脑炎病毒、辽宁病毒、Tahyna病毒、蜱传脑炎及西尼罗病毒均为阴性。结论　2019—2020年哈密市存在尖音库蚊、里海伊蚊、阿拉斯加脉毛蚊3种蚊虫,以尖音库蚊为优势蚊种;所捕获尖音库蚊均为指名亚种,未发现蚊类携带相关虫媒病毒。     

关于寨卡病毒病五个常见问题

正2015年11月以来,美洲等多个国家相继出现了寨卡病毒病病例。12月1日,世界卫生组织发布了关于寨卡病毒的全球警告。一、什么是寨卡病毒病?寨卡病毒病是由寨卡病毒引起并通过蚊媒叮咬传播给人类的病毒性疾病,属于人-畜共患疾病。"寨卡"是乌干达语"Zika",意思是"杂草"。寨卡病毒于1947年被首次发现,属于黄病毒家族,与乙型脑炎病毒、登革热病毒、西尼罗病毒近亲,通过伊蚊叮咬在人和动物间传播。     

新疆地区虫媒病毒调查研究状况

近年来新疆陆续发现的一些新的虫媒病毒与虫媒病毒病对当地人畜健康造成一定危害.新疆地理生态环境的复杂多样性为多种虫媒病毒的传播提供了有利条件,虫媒病毒在新疆分布广泛,存在地域差异性.随着分子流行病学的发展,基于核酸分子和细胞培养检测技术方法从新疆的多种昆虫媒介和宿主动物中鉴定并分离得到分属于黄病毒科,披膜病毒科,呼肠孤病毒科和布尼亚病毒科的多种病毒,部分病毒属在新疆系首次发现.本文对新疆多个地区近年来已报道的虫媒病毒在宿主中的检测和感染人畜引起的疾病的情况进行了汇总整理,有利于对新疆各地虫媒病毒的流行病学进行深入的调查与研究.     

东北地区人血清虫媒病毒抗体调查

<正> 虫媒病毒是指能在蚊子、蜱、白蛉等节肢动物体内繁殖并通过叮咬脊椎动物而传播疾病的病毒。近年来研究进展较快,至1988年,世界上已登记的虫媒病毒有532种,其中125种证明可引起人类发病。 我国已分离鉴定的虫媒病毒有流行性乙型脑炎、     

西尼罗病毒的感染、蔓延及其警示

西尼罗病毒(West Nile virus,WNV)是一种RNA病毒,属虫媒病毒黄病毒科、黄病毒属,能引起人畜共患疾病。该病毒首次于1937年在西尼罗地区乌干达分离到,因此而得名,曾在非洲、欧洲、中东、西亚、中亚等地区发现。自从1999年WNV在美国纽约暴发性流行以来,随后短短几年迅速在美国蔓延。以往的WNV感染者仅有轻微发热,称为西尼罗热(West Nile Fever,WNF),但是最近的几次大流行中。     

第一讲 病毒的基本概念及病毒的发病学

病毒引起的人类疾患远远超过了其他微生物的感染;多数急性感染是由病毒所引起的。常见的病毒性疾病如伤风、流感、麻疹、水痘、肝炎、乙型脑炎、脊髓灰质炎等,不仅感染性强,流行广泛,而且目前还很少有特效药物。近25年来,由于病毒培养和病毒诊断技术的进展,发现了很多新病毒:包括呼吸道感染病毒、肠道感染病毒、虫媒病毒、慢病毒和肿瘤病毒等。临床医生日常医疗实践中经常碰到     

输入性登革热七例

登革热是由伊蚊传播登革病毒所致的急性传染病。临床特征为发热，头痛，全身肌肉、骨骼和关节痛，乏力，皮疹，淋巴结肿大及WBC减少。登革热在全球热带和亚热带100多个国家和地区广泛流行。张海林等对云南登革热作了研究，云南省未发现埃及伊蚊分布，但白纹伊蚊分布广泛。1975年及1981年至1983年的7～9月，在云南河口、西双版纳采集的白纹伊蚊标本中分离出登革4型和登革3型病毒。从当地发热患者血清中查到登革抗体，说明有散在患者存在。云南过去曾发生输入性登革热。     

云南省通海县蚊虫2株乙型脑炎病毒的分离鉴定北大核心CSCD

目的了解云南省通海县蚊虫携带的乙型脑炎病毒(JEV)情况、分子特征及基因分型。方法2015年7月在云南省玉溪市通海县采用诱蚊灯在调查点通宵捕捉蚊虫,蚊虫研磨后分别接种BHK-21和C6/36细胞进行病毒分离,使用黄病毒属特异引物进行初步鉴定,使用乙型脑炎病毒E基因特异引物进行RT-PCR扩增及测序,使用Megalign、Genedoc、Mega7等软件进行序列分析。结果共捕获三带喙库蚊、中华按蚊、致倦库蚊和骚扰阿蚊2300只,其中三带喙库蚊为优势蚊种(78%)。分46批进行病毒分离,获得2株阳性分离物,接种BHK-21细胞96h,引起细胞病变。使用黄病毒属特异引物和乙型脑炎病毒E基因特异引物扩增均为阳性。序列分析结果显示,2株新分离乙型脑炎病毒与疫苗株SA14-14-2在E基因存在12个氨基酸差异位点,在8个与乙脑病毒毒力相关的位点上存在6个差异位点。E基因遗传进化分析显示,2株新分离病毒与基因Ⅰ型乙型脑炎病毒位于同一进化分支,核苷酸和氨基酸同源性分别为91.8%~99.1%和98.0%~100%。遗传进化分析显示,其与云南2016年蚊虫中分离的乙脑病毒株JEV/mosq/YN/2016亲缘关系较近,核苷酸和氨基酸同源性分别为99.1%和99.8%。结论云南省通海县分离的2株病毒鉴定为基因Ⅰ型乙型脑炎病毒,其与云南省近年来流行的毒株遗传进化关系较近。2毒株的E基因上与毒力相关的关键位点中有2个位点发生突变,结构域Ⅲ的关键抗原未发生改变,因此SA14-14-2减毒疫苗株仍可用于该地区人群的免疫接种,以预防乙型脑炎的发生和流行。     

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.     

Imported arbovirus infections in Canada 1974-89

From 1974 to 1989, sera from symptomatic patients with histories of recent travel outside Canada were tested for antibodies to several arboviruses, principally of the alphavirus and flavivirus families. Diagnostic seroconversions were documented in 84 individuals from six provinces, including one alphavirus (Chikungunya) and 83 flavivirus seroconvertors. Dengue 1 virus was isolated from the blood of one patient. Most flavivirus seroconvertors were likely infected with dengue virus, but infections with tick-borne encephalitis, St Louis encephalitis and Powassan viruses were also recognized. Patients had histories of recent travel to the Caribbean, South America, Asia, Africa, North America (outside Canada), Tahiti, Fiji and Europe. Possible imported infections due to Japanese encephalitis, Ross River, western equine encephalitis and Colorado tick fever viruses were also encountered.     

Imported arbovirus infections in Canada 1974�C89

From 1974 to 1989, sera from symptomatic patients with histories of recent travel outside Canada were tested for antibodies to several arboviruses, principally of the alphavirus and flavivirus families. Diagnostic seroconversions were documented in 84 individuals from six provinces, including one alphavirus (Chikungunya) and 83 flavivirus seroconvertors. Dengue 1 virus was isolated from the blood of one patient. Most flavivirus seroconvertors were likely infected with dengue virus, but infections with tick-borne encephalitis, St Louis encephalitis and Powassan viruses were also recognized. Patients had histories of recent travel to the Caribbean, South America, Asia, Africa, North America (outside Canada), Tahiti, Fiji and Europe. Possible imported infections due to Japanese encephalitis, Ross River, western equine encephalitis and Colorado tick fever viruses were also encountered.     

Dengue and other emerging flaviviruses

Flaviviruses are among the most important emerging viruses known to man. Most are arboviruses (arthropod-borne) being transmitted by mosquitoes or ticks. They derived from a common ancestor 10-20000 years ago and are evolving rapidly to fill new ecological niches. Many are spreading to new geographical areas and causing increased numbers of infections. Traditionally, three clinical syndromes are recognized: fever-arthralgia-rash, viral haemorrhagic fever, and neurological disease, though for some flaviviruses the disease pattern is changing. Dengue, the most important flavivirus, is transmitted between humans by Aedes mosquitoes. Recent work is elucidating the pathogenesis of its most severe form, dengue haemorrhagic fever. Yellow fever, which has epidemiological similarities to dengue, was under control in the mid-20th century, but is once again increasing. Japanese encephalitis virus is numerically the most important cause of epidemic encephalitis; its geographical area is expanding despite the availability of vaccines. Other mosquito-borne neurotropic flaviviruses with clinical and epidemiological similarities are found across the globe. These include St Louis encephalitis virus, Murray Valley encephalitis virus, and West Nile virus, which recently reached the Americas for the first time. In cooler northern climates ticks are more important vectors. Tick-borne encephalitis virus occurs across large parts of Eastern Europe and the Commonwealth of Independent states. The tick-borne haemorrhagic flaviviruses, Omsk haemorrhagic fever and Kyasanur Forrest disease are localized in small areas.     

Arbovirus investigations in Argentina, 1977-1980. I. Historical aspects and description of study sites

This is the introductory paper to a series on the ecology of arboviruses in Argentina. Epizootics of equine encephalitis have occurred since at least 1908, principally in the Pampa and Espinal biogeographic zones, with significant economic losses; human cases of encephalitis have been rare or absent. Both western equine and eastern equine encephalitis viruses have been isolated from horses during these epizootics, but the mosquitoes responsible for transmission have not been identified. A number of isolations of Venezuelan equine encephalitis (VEE) virus were reported between 1936 and 1958 in Argentina, but the validity of these findings has been seriously questioned. Nevertheless, serological evidence exists for human infections with a member of the VEE virus complex. Serological surveys conducted in the 1960s indicate a high prevalence of infection of humans and domestic animals with St. Louis encephalitis (SLE), and 2 SLE virus strains have been isolated from rodents. Human disease, however, has rarely been associated with SLE infection. Only 7 isolations of other arboviruses have been described (3 of Maguari, 1 of Aura, 2 of Una, and 1 of an untyped Bunyamwera group virus). In 1977, we began longitudinal field studies in Santa Fe Province, the epicenter of previous equine epizootics, and in 1980 we extended these studies to Chaco and Corrientes provinces. The study sites are described in this paper.     

Developmental disorders of the fetus in some arthropod-borne virus infections

A number of arboviruses have been associated with congenital defects in domestic aminals and man. In this review comparison is made of the temporal association between epidemics of arboviruses affecting man and animals in which there is an obvious relationship between the infection and the fetal defects, and arboviruses which cause no overt clinical symptoms in the vertebrate host but result in deformities of the fetus. The danger to the fetus following the use of live attenuated virus vaccines against several important arbovirus diseases is also examined. It is concluded that arboviruses which are capable of infecting humans or animals without producing overt clinical signs, and attenuated vaccine viruses pose the greatest threat to the fetus.     

Arboviral Bottlenecks and Challenges to Maintaining Diversity and Fitness during Mosquito Transmission

The term arbovirus denotes viruses that are transmitted by arthropods, such as ticks, mosquitoes, and other biting arthropods. The infection of these vectors produces a certain set of evolutionary pressures on the virus; involving migration from the midgut, where the blood meal containing the virus is processed, to the salivary glands, in order to transmit the virus to the next host. During this process the virus is subject to numerous bottlenecks, stochastic events that significantly reduce the number of viral particles that are able to infect the next stage. This article reviews the latest research on the bottlenecks that occur in arboviruses and the way in which these affect the evolution and fitness of these viruses. In particular we focus on the latest research on three important arboviruses, West Nile virus, Venezuelan equine encephalitis virus and Chikungunya viruses and compare the differing effects of the mosquito bottlenecks on these viruses as well as other evolutionary pressures that affect their evolution and transmission.     

New developments in flavivirus vaccines with special attention to yellow fever

PURPOSE OF REVIEW: Here we review recent epidemiological trends in flavivirus diseases, findings related to existing vaccines, and new directions in flavivirus vaccine research. We emphasize the need for stepped-up efforts to stop further spread and intensification of these infections worldwide. RECENT FINDINGS: Although the incidence and geographic distribution of flavivirus diseases have increased in recent years, human vaccines are available only for yellow fever, Japanese encephalitis, tick-borne encephalitis and Kyasanur forest disease. Factors contributing to resurgence include insufficient supplies of available vaccines, incomplete vaccination coverage and relaxation in vector control. Research has been underway for 60 years to develop effective vaccines against dengue, and recent progress is encouraging. The development of vaccines against West Nile, virus recently introduced to North America, has been initiated. In addition, there is considerable interest in improving existing vaccines with respect to increasing safety (e.g. eliminating the newly recognized syndrome of yellow fever vaccine-associated viscerotropic adverse disease), and to reducing the cost and number of doses required for effective immunization. SUMMARY: Traditional approaches to flavivirus vaccines are still employed, while recent advancements in biotechnology produced new approaches to vaccine design, such as recombinant live virus, subunit and DNA vaccines. Live chimeric vaccines against dengue, Japanese encephalitis and West Nile based on yellow fever 17D virus (ChimeriVax) are in phase I/II trials, with encouraging results. Other chimeric dengue, tick-borne encephalitis and West Nile virus candidates were developed based on attenuated dengue backbones. To further reduce the impact of flavivirus diseases, vaccination policies and vector control programs in affected countries require revision.     

Full Genome Sequencing of Three Sedoreoviridae Viruses Isolated from Culicoides spp. (Diptera,Ceratopogonidae) in China

Sedoreoviridae is a family of viruses belonging to the order Reovirales and comprises six genera, two of which, Orbivirus and Seadornavirus, contain arboviruses that cause disease in humans and livestock. Areas such as Yunnan Province in southwestern China, have high arboviral activity due in part to warm and wet summers, which support high populations of biting flies such as mosquitoes and Culicoides. Three viral isolates previously obtained from Culicoides collected at cattle farms in Shizong County of Yunnan Province, China, between 2019 and 2020 were completely sequenced and identified as Banna virus (BAV) genotype A of Seadornavirus and serotypes 1 and 7 of epizootic hemorrhagic disease virus (EHDV) of Orbivirus. These results suggest that Culicoides tainanus and C. orientalis are potential vectors of BAV and EHDV, respectively, and represent the first association of a BAV with C. tainanus and of an arbovirus with C. orientalis. Analysis using VP9 generally agreed with the current groupings within this genus based on VP12, although the classification for some strains should be corrected. Furthermore, the placement of Kadipiro virus (KDV) and Liao ning virus (LNV) in Seadornavirus may need confirmation as phylogenetic analysis placed these viruses as sister to other species in the genus.