猪戊型肝炎病毒最新研究进展

戊型肝炎（Hepatitis E）是由戊型肝炎病毒（Hepatitis Evirus,HEV）引起的以黄疸为主的急性病毒性肝炎。戊型肝炎主要经粪一口途径传播,有流行和散发两种形式。流行主要发生在亚洲、非洲、美洲等发展中国家,因水源被污染引起。散发则主要发生在欧美一些发达国家。     

猪戊型肝炎病毒研究进展

猪戊型肝炎是由戊型肝炎病毒（HEV）感染引起的经肠道传播的急性病毒性肝炎,主要通过粪口途径传播。而戊型肝炎病毒是近年来发现的一种新型病毒。     

猪戊型肝炎的研究进展

戊型肝炎是由戊型肝炎病毒（HepatitisEvirus,HEV）引起的一种急性、自限性病毒性肝炎,主要经粪一口途径传播,通常是由于饮用被HEV污染的水源而引起,在青壮年表现为暴发性肝炎的比例较高,死亡率在0．5％。3％,但在孕妇中死亡率可高达15％～20％。1997年,美国学者Meng发现了猪源的戊型肝炎病毒,随后各发达国家及印度等国陆续都有相关的报道,确定戊型肝炎为一种人畜共患病,并成为各国密切关注的公共卫生问题。     

戊型肝炎病毒ORF3蛋白功能的研究进展

戊型肝炎是由戊型肝炎病毒感染引起的经肠道传播的人兽共患疾病,文章就戊型肝炎病毒开放阅读框ORF3编码蛋白在细胞信号转导、病毒颗粒的释放及机体免疫抑制方面的功能研究进行了综述,旨在为深入研究戊型肝炎病毒的致病机理及抗戊型肝炎病毒疫苗的开发提供参考。     

人畜共患戊型肝炎的流行病学研究进展

戊型肝炎是由戊型肝炎病毒引起的一种自限性疾病,既往称肠道传播的非甲非乙型肝炎,临床症状与甲型肝炎极为相似.目前发现5个基因型,而且呈明显的地域性分布,主要分布于亚洲、非洲和中美洲的发展中国家,有流行性和散发性两种形式,其中以流行性为主.该病毒主要以经粪-口途径传播,与人畜关系密切,可引起人和牲畜严重的疾病.对戊型肝炎病毒的流行特点及途径作了一些简要分析,希望能对戊型肝炎的流行、预防研究提供参考.     

戊型肝炎病毒研究新进展

戊型肝炎病毒(hepatitis Evirus,HEV)是非甲非乙型急性肝炎的病原体,主要经粪-口途径传播,也有报道可以通过血液传播。戊型肝炎在亚洲、非洲及美洲的墨西哥等发展中国家常呈爆发流行,我国1986-1988年在新疆曾经发生戊型肝炎暴发流行[1],而在包括发达国家在内的世界各地呈散在传     

鸡西地区猪戊型肝炎病毒的检测及序列分析

本文探讨鸡西地区猪戊型肝炎病毒检测结果及分析其序列特征．为确定本地区猪戊型肝炎病毒基因型提供可靠依据。方法：在鸡西地区采集600份猪粪便样本作为本次研究对象．经PCR后检测HEV—RNA阳性率及分析序列,记录结果并给予统计学分析后得出结论。结果：600份猪粪便样本中106份经检测为HEV—RNA阳性（阳性率17．67％）,494份阴性（阴性率82．33％）,阳性样本序列与基因IV型相似度最高,对比结果具有统计学意义（P〈0．05）。结论：养殖工作者及防疫工作者应提高警惕,将预防及干预猪戊型肝炎病毒感染作为工作重点．采取多种有效措施降低猪感染戊型肝炎病毒的几率．阻断人畜共患疾病传播途径,保障人们饮食健康。     

动物戊型肝炎病毒研究进展

<正>戊型肝炎是一种由戊型肝炎病毒引起的,既往称肠道传播的非甲非乙型肝炎。1983年前苏联学者Balayan等首次用免疫电镜技术从一名志愿受试者粪便中观察到戊型肝炎病毒颗粒。1989年在东京召开的国际会议上,正式将此型肝炎及相关病毒分别命名为戊型肝炎(hepatitis E,HE)和戊型肝炎病毒(hepatitis E virus,HEV)。     

猪戊型肝炎诊断方法的研究进展

戊型肝炎(Hepatitis E,HE)是由戊型肝炎病毒(Hepatitis E virus,HEV)感染引起的一种急性、自限性疾病,病毒经粪-口途径传播,其暴发和流行主要分布在发展中国家,常因饮用水被污染而引起,散发病例呈全球分布。1997年,发现了动物源性的戊型肝炎病毒,随后,各发达国家及印度等国陆续都有猪HEV的相关报道,     

戊型肝炎病毒分子生物学及疫苗研究进展

戊型肝炎是由戊型肝炎病毒感染会引起一种急性、自限性疾病。病毒采取粪-口途径进行传播。在发展中国家是主要的病毒性肝炎的病原体。与其他病毒性肝炎相比戊型肝炎的奇怪特征是感染的怀孕妇女的病死率很高。由于缺乏体外可行的繁育系统,有些地方分离的戊型肝炎病毒在灵长类人猿中保存。其后病毒的基因组被克隆出来,其核酸序列也已经测出。戊型肝炎病毒现在临时归入类戊型肝炎病毒类家族。病毒核酸基因组:正链RNA,7.5kb大小。编码至少三种蛋白质,ORF1编码病毒的非结构多聚蛋白,这些蛋白具有与其他正链RNA病毒的复制酶和加工酶同源的活性…     

Familial Hepatitis E Outbreak Linked to Wild Boar Meat Consumption

An HIV‐infected patient was diagnosed with acute hepatitis E infection in our hospital. An epidemiological inquiry was performed to collect demographic, food and animal exposure variables in order to identify the potential route of transmission. The patient reported that his family traditionally hunted wild boar for food. All family members were analysed for hepatitis E virus infection. Additionally, route of transmission by wild boar meat consumption and prevalence of HEV infection among wild boar from the same hunting area were investigated. In all‐family members (n = 8), HEV‐RNA was amplified. Two wild boar meat slices consumed was analysed, showing the presence of HEV. The virus isolated was consistent with genotype 3, revealing 100% homology between family members and meat. Additionally, we tested nine wild boar hunted in the same hunting area. All of them were RNA‐HEV positive, isolating the same HEV genotype 3 viral strain. We demonstrated by phylogenetic analysis zoonotic transmission of HEV by wild boar meat consumption. The prevalence of HEV infection among wild boar found in our study suggests that this species is an important route of transmission to human.     

Pigs orally inoculated with swine hepatitis E virus are able to infect contact sentinels

The purpose of the present study was to explore the most likely natural route of infection of swine hepatitis E virus (HEV) by oral inoculation of pigs and to investigate the potential infection by direct contact exposure. A preliminary experiment was performed to assess the infectiousness of the bile used as source of virus. Once confirmed, 16 pigs were inoculated via oral drop with an HEV positive bile suspension containing 2 × 10⁵ genome equivalents per pig. Nine animals were kept as contact sentinels and 12 more pigs were used as negative controls. A number of pigs from the three groups were euthanized at 16, 32 and 64 days post-inoculation. From the HEV inoculated group, three pigs shed virus in faeces, two had virus RNA in bile at necropsy and two seroconverted. In the contact group, two animals showed presence of HEV RNA in bile. This study demonstrates that pigs orally inoculated with a single HEV dose got infection, although few animals had evidence of infection. Moreover, the virus was successfully transmitted to direct contact exposed pigs.     

Haemorrhagic enteritis of turkeys – current knowledge

Haemorrhagic enteritis virus (HEV), an adenovirus associated with acute haemorrhagic gastro-intestinal disease of 6–11-week old turkeys predominantly hampers both humoral and cellular immunity. Affected birds are more prone to secondary complications (e.g. colibacillosis and clostridiosis) and failure to mount an effective vaccine-induced immune response. HEV belongs to the new genus Siadenovirus. Feco-oral transmission is the main route of entry of the virus and it mainly colonizes bursa, intestine and spleen. Both naturally occurring virulent and avirulent strains of HEVs are serologically indistinguishable. Recent findings revealed that ORF1, E3 and fib genes are the key factors affecting virulence. The adoption of suitable diagnostic tools, proper vaccination and biosecurity measures have restrained the occurrence of disease epidemics. For diagnostic purposes, the best source of HEV is either intestinal contents or samples from spleen. For rapid detection highly sensitive and specific tests such as quantitative real-time PCR based on Taq man probe has been designed. Avirulent strains of HEV or MSDV can be effectively used as live vaccines. Novel vaccines include recombinant hexon protein-based subunit vaccines or recombinant virus-vectored vaccines using fowl poxvirus (FPV) expressing the native hexon of HEV. Notably, subunit vaccines and recombinant virus vectored vaccines altogether offer high protection against challenge or field viruses. Herein, we converse a comprehensive analysis of the HEV genetics, disease pathobiology, advancements in diagnosis and vaccination along with appropriate prevention and control strategies.     

猪血凝性脑脊髓炎病毒在人工感染仔猪体内侵染过程和分布规律的研究

为研究血凝性脑脊髓炎病毒(HEY)在人工感染仔猪体内的侵袭过程和分布规律,本实验采用滴鼻的方式感染5头1日龄未食初乳仔猪,并在感染后每隔24 h迫杀1头仔猪,采集鼻黏膜、气管、口腔黏膜、舌、食管、胃、肠、心肌、肝、脾、肺、肾、各段脊髓和脑等组织脏器制作切片,通过间接免疫组织化学方法检测HEV在仔猪体内的动态侵袭过程.此外,采用SYBR Green Ⅰ实时荧光定量PCR(Real-time PCR)方法检测病毒在各组织脏器中的分布情况.结果显示:感染病毒后2 d～3 d,仔猪出现精神沉郁、全身震颤等中枢神经系统症状,免疫组织化学检测可见病毒抗原首先出现于脑桥,并进一步蔓延至延髓和各段脊髓,最后进入小脑浦肯野氏细胞和大脑皮层锥体细胞中;Real-time PCR检测结果显示病毒广泛分布于大脑皮层、脑桥、延髓、脊髓和小脑等中枢神经系统的组织中,其中大脑皮层的检出率最高.     

Natural and experimental hepatitis E virus genotype 3 - infection in European wild boar is transmissible to domestic pigs

Hepatitis E virus (HEV) is the causative agent of acute hepatitis E in humans in developing countries, but sporadic and autochthonous cases do also occur in industrialised countries. In Europe, food-borne zoonotic transmission of genotype 3 (gt3) has been associated with domestic pig and wild boar. However, little is known about the course of HEV infection in European wild boar and their role in HEV transmission to domestic pigs. To investigate the transmissibility and pathogenesis of wild boar-derived HEVgt3, we inoculated four wild boar and four miniature pigs intravenously. Using quantitative real-time RT-PCR viral RNA was detected in serum, faeces and in liver, spleen and lymph nodes. The antibody response evolved after fourteen days post inoculation. Histopathological findings included mild to moderate lymphoplasmacytic hepatitis which was more prominent in wild boar than in miniature pigs. By immunohistochemical methods, viral antigens were detected mainly in Kupffer cells and liver sinusoidal endothelial cells, partially associated with hepatic lesions, but also in spleen and lymph nodes. While clinical symptoms were subtle and gross pathology was inconspicuous, increased liver enzyme levels in serum indicated hepatocellular injury. As the faecal-oral route is supposed to be the most likely transmission route, we included four contact animals to prove horizontal transmission. Interestingly, HEVgt3-infection was also detected in wild boar and miniature pigs kept in contact to intravenously inoculated wild boar. Given the high virus loads and long duration of viral shedding, wild boar has to be considered as an important HEV reservoir and transmission host in Europe.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-014-0121-8) contains supplementary material, which is available to authorized users.     

Seroepidemiology and genotyping of hepatitis E virus in Singapore reveal rise in number of cases and similarity of human strains to those detected in pig livers

Hepatitis E virus (HEV) causes 20 million infections worldwide yearly, of which only about 3.3 million are symptomatic. In developed Asian countries, HEV strains detected in human sera and in food sources were genetically similar, suggesting that indigenous HEV infections may be largely food‐borne. To assess the burden of hepatitis E in Singapore, we performed a seroepidemiologic study of the infection. Additionally, we carried out HEV genotyping on archived, residual HEV IgM‐positive serum samples collected between 2014 and 2016 (n = 449), and on pig liver samples (n = 36) purchased from wet markets and supermarkets. Our study shows a rise in hepatitis E incidence (IgM) from 1.7 to 4.1 cases per 100,000 resident population from 2012 to 2016 and an increase in hepatitis E IgG positivity rate among residents from 14% in 2007 to 35% in 2016. Other findings also suggest the epidemiology of hepatitis E in Singapore has shifted, from it being mainly a disease imported from the Indian subcontinent, to one that is now increasingly prevalent in our resident population. Genotypes obtained from 143 human samples identified the majority to be genotype 3 (n = 121), 21 to be genotype 1 and one to be genotype 4. Further phylogenetic analyses suggest genotype 3a to be the cause of indigenous infections in residents, which showed genetic similarity to the genotype 3a strains detected in pig livers. This link between the strains in the majority of human samples and those in pig livers consumed by the public suggests a possible food‐borne route of HEV infection in Singapore.     

Hepatitis E viruses in humans and animals

Hepatitis E virus (HEV) is an emerging pathogen belonging to a newly recognized family of RNA viruses (Hepeviridae). HEV is an important enterically transmitted human pathogen with a worldwide distribution. It can cause sporadic cases as well as large epidemics of acute hepatitis. Epidemics are primarily waterborne in areas where water supplies are contaminated with HEV of human origin. There is increasing evidence, however, that many animal species are infected with an antigenically similar virus. A recently isolated swine virus is the best candidate for causing a zoonotic form of hepatitis E. The virus is serologically cross-reactive with human HEV and genetically very similar, and the human and swine strains seem to be cross-infective. Very recent evidence has also shown that swine HEV, and possibly a deer strain of HEV, can be transmitted to humans by consumption of contaminated meat. In this review, we discuss the prevalence, pathogenicity, diagnosis and control of human HEV, swine HEV, the related avian HEV and HEV in other hosts and potential reservoirs.     

The high prevalence of hepatitis E virus infection in wild boars in Ibaraki Prefecture,Japan

Hepatitis E virus (HEV) is known as a causative agent of zoonosis and food poisoning. Pigs and some species of wild animals, including wild boar, are known to be a reservoir of HEV. In this study, we investigated the situation regarding HEV infection in wild boars in Ibaraki Prefecture, Japan. Serum, liver and feces samples from 68 animals were collected, and the presence or absence of HEV genomic RNA and HEV antibodies were analyzed. The viral genome was detected in samples from 7 (10.3%) animals, with all HEVs classified as genotype 3, subtype 3b. HEV antibodies were detected in samples from 28 (41%) animals. This report demonstrates for the first time the high prevalence of HEV infection in wild boars in Ibaraki Prefecture.     

Zoonotic hepatitis E: animal reservoirs and emerging risks

Hepatitis E virus (HEV) is responsible for enterically-transmitted acute hepatitis in humans with two distinct epidemiological patterns. In endemic regions, large waterborne epidemics with thousands of people affected have been observed, and, in contrast, in non-endemic regions, sporadic cases have been described. Although contaminated water has been well documented as the source of infection in endemic regions, the modes of transmission in non-endemic regions are much less known. HEV is a single-strand, positive-sense RNA virus which is classified in the Hepeviridae family with at least four known main genotypes (1–4) of mammalian HEV and one avian HEV. HEV is unique among the known hepatitis viruses, in which it has an animal reservoir. In contrast to humans, swine and other mammalian animal species infected by HEV generally remain asymptomatic, whereas chickens infected by avian HEV may develop a disease known as Hepatitis-Splenomegaly syndrome. HEV genotypes 1 and 2 are found exclusively in humans while genotypes 3 and 4 are found both in humans and other mammals. Several lines of evidence indicate that, in some cases involving HEV genotypes 3 and 4, animal to human transmissions occur. Furthermore, individuals with direct contact with animals are at higher risk of HEV infection. Cross-species infections with HEV genotypes 3 and 4 have been demonstrated experimentally. However, not all sources of human infections have been identified thus far and in many cases, the origin of HEV infection in humans remains unknown.     

Detection of hepatitis E virus RNA in rats caught in pig farms from Northern Italy

Hepatitis E virus (HEV) strains belonging to the Orthohepevirus genus are divided into four species (A–D). HEV strains included in the Orthohepevirus A species infect humans and several other mammals. Among them, the HEV‐3 and HEV‐4 genotypes are zoonotic and infect both humans and animals, of which, pigs and wild boar are the main reservoirs. Viruses belonging to the Orthohepevirus C species (HEV‐C) have been considered to infect rats of different species and carnivores. Recently, two studies reported the detection of HEV‐C1 (rat HEV) RNA in immunocompromised and immunocompetent patients, suggesting a possible transmission of rat HEV to humans. The role of rats and mice as reservoir of HEV and the potential zoonotic transmission is still poorly known and deserves further investigation. To this purpose, in this study, the presence of HEV RNA was investigated in the intestinal contents and liver samples from 47 Black rats (Rattus rattus) and 21 House mice (Mus musculus) captured in four pig farms in Northern Italy. The presence of both Orthohepevirus A and C was investigated by the real‐rime RT‐PCR specific for HEV‐1 to HEV‐4 genotypes of Orthohepevirus A species and by a broad spectrum hemi‐nested RT‐PCR capable of detecting different HEV species including rat HEV. The intestinal content from two Black rats resulted positive for HEV‐C1 RNA and for HEV‐3 RNA, respectively. None of the House mice was HEV RNA positive. Sequence analyses confirmed the detection of HEV‐C1, genotype G1 and HEV‐3 subtype e. The viral strain HEV‐3e detected in the rat was identical to swine HEV strains detected in the same farm. Liver samples were negative for the detection of either rat HEV or HEV‐3.