Effect of Hepatitis E Virus RNA Universal Blood Donor Screening,Catalonia, Spain, 2017‒2020

Hepatitis E virus (HEV) is the major cause of acute viral hepatitis in several countries in Europe. HEV is acquired mainly by consumption of contaminated pork but can also be transmitted through blood transfusion. HEV infection is usually self-limited but can become persistent in immunocompromised persons. During the first 30 months of HEV RNA universal screening of blood donations in Catalonia, Spain, we identified 151 HEV RNA–positive donations (1/4,341 blood donations). Most infected donors reported consumption of pates and sausages, and 58% were negative for HEV IgM and IgG. All HEV isolates belonged to genotype 3. All infected donors spontaneously resolved the infection, and no neurologic symptoms and reinfections were observed after 1 year of follow-up. Since the implementation of HEV RNA universal screening, no new cases of transfusion-transmitted HEV infection were reported. Our data indicate HEV screening of blood donations provides safer blood for all recipients, especially for immunosuppressed persons.     

Hepatitis E virus and neurologic disorders

Information about the spectrum of disease caused by hepatitis E virus (HEV) genotype 3 is emerging. During 2004-2009, at 2 hospitals in the United Kingdom and France, among 126 patients with locally acquired acute and chronic HEV genotype 3 infection, neurologic complications developed in 7 (5.5%): inflammatory polyradiculopathy (n = 3), Guillain-Barre syndrome (n = 1), bilateral brachial neuritis (n = 1), encephalitis (n = 1), and ataxia/proximal myopathy (n = 1). Three cases occurred in nonimmunocompromised patients with acute HEV infection, and 4 were in immunocompromised patients with chronic HEV infection. HEV RNA was detected in cerebrospinal fluid of all 4 patients with chronic HEV infection but not in that of 2 patients with acute HEV infection. Neurologic outcomes were complete resolution (n = 3), improvement with residual neurologic deficit (n = 3), and no improvement (n = 1). Neurologic disorders are an emerging extrahepatic manifestation of HEV infection.     

Protection of chickens against avian hepatitis E virus (avian HEV) infection by immunization with recombinant avian HEV capsid protein

Avian hepatitis E virus (avian HEV) is an emerging virus associated with hepatitis-splenomegaly syndrome in chickens in North America. Avian HEV is genetically and antigenically related to human HEV, the causative agent of hepatitis E in humans. In the lack of a practical animal model, avian HEV infection in chickens has been used as a model to study human HEV replication and pathogenesis. A 32 kDa recombinant ORF2 capsid protein of avian HEV expressed in Escherichia coli was found having similar antigenic structure as that of human HEV containing major neutralizing epitopes. To determine if the capsid protein of avian HEV can be used as a vaccine, 20 chickens were immunized with purified avian HEV recombinant protein with aluminum as adjuvant and another 20 chickens were mock immunized with KLH precipitated in aluminum as controls. Both groups of chickens were subsequently challenged with avian HEV. All the tested mock-immunized control chickens developed typical avian HEV infection characterized by viremia, fecal virus shedding and seroconversion to avian HEV antibodies. Gross hepatic lesions were also found in portion of these chickens. In contrast, none of the tested chickens immunized with avian HEV capsid protein had detectable viremia, fecal virus shedding or observable gross hepatitis lesions. The results from this study suggested that immunization of chickens with avian HEV recombinant ORF2 capsid protein with aluminum as adjuvant can induce protective immunity against avian HEV infection. Chickens are a useful small animal model to study anti-HEV immunity and pathogenesis.     

上海市部分地区散发性戊型肝炎病毒基因型别和发病危险因素研究

目的探讨上海市部分地区急性散发性戊型肝炎（戊肝）病毒（HEV）型别和发病危险因素.方法用巢式RT-PCR方法检测HEV序列,并进行序列的同源性比较分析;同时采取1：2病例对照研究的方法,选取上海市3个区2003-2004年急性散发性确诊戊肝86例住院病例,分别配以本区和其他区健康人群对照组,用单因素和多因素logistlc回归模型进行分析.结果病毒序列分析表明戊肝病例中的HEV病毒序列属于Ⅳ型;单因素分析结果显示居住条件、外出就餐、有海鲜河鲜食用史等均为戊肝发病的危险因素;多因素分析结果显示海鲜（生、炝）食用史（OR=7.048）是戊肝感染 的危险因素.结论上海市部分地区散发性HEV流行株以Ⅳ型病毒株为主,海鲜（生、炝）食用史等是戊肝发病的危险因素.     

Protective role of humoral immune responses during an outbreak of hepatitis E in Egypt

Although the seroprevalence of hepatitis E virus (HEV) is approximately 80% in adult Egyptians living in rural areas, symptomatic HEV-caused acute viral hepatitis (AVH) is sporadic and relatively uncommon. To investigate the dichotomy between HEV infection and clinical AVH, HEV-specific immune responses in patients with symptomatic and asymptomatic HEV infection during a waterborne outbreak in Egypt were examined. Of 235 acute hepatitis patients in Assiut hospitals screened for HEV infection, 42 (17.9%) were acute hepatitis patients confirmed as HEV-caused AVH; 37 (88%) of the 42 patients were residents of rural areas, and 14 (33%) were from one village (Kom El-Mansoura). Another 200 contacts of AVH cases in this village were screened for HEV and 14 (7.0%), all of whom were family members of AVH cases, were asymptomatic HEV IgM-positive. HEV infections in this village peaked during the summer. Asymptomatic HEV seroconverters had significantly higher levels of epitope-specific neutralising (p=0.006) and high avidity (p=0.04) anti-HEV antibodies than the corresponding AVH cases. In conclusion, naturally acquired humoral immune responses appear to protect HEV-exposed subjects from AVH during an HEV outbreak in Egypt.     

上海地区猪戊型肝炎感染状况及病毒序列分析

[目的] 调查上海地区猪戊型肝炎感染现况,掌握上海市猪感染戊型肝炎病毒的型别,以进一步探讨猪戊型肝炎感染与病人感染的可能关系。[方法]采集上海市3个区的不同季度的3月龄猪血样,用ELISA法检测抗-HEV 特异性抗体水平,并用RT-nPCR方法检测猪粪便中HEV病毒,进行RNA核酸序列分析和基因进化树分析。 [结果] 共检测猪血清标本1 798份,HEV抗体阳性率为89．38％;44份猪粪便样品中17份RT、-nPCR为阳性,HEV RNA阳性率为38．64％,病毒序列经同源性分析,与戊型肝炎病毒I、Ⅱ、Ⅲ、Ⅳ型的同源性分别为78．5％-84．0％、76．5％-80．7％、 77．3％-82．7％、84．6％-90．7％,基因进化树的分析显示,病毒序列与HEVⅣ型的ⅣA形成同一分支。[结论] 上海地区的猪戊型肝炎感染率较高,戊型肝炎病毒型别属基因型Ⅳ型。     

男男同性性行为者HEV感染危险因素研究

目的 了解男男同性性行为人群(man who have sex with man,MSM)戊型肝炎病毒(hepatitis E virus,HEV)感染情况,并分析MSM高危行为方式与HEV感染之间的关系,为开展有针对性的开展健康教育和行为干预提供依据.方法 采用统一设计的调查问卷进行调查,问卷内容包括基本人口学特征、性行为特征及安全套使用情况,用酶联免疫吸附法(enzyme-linked immunosorbent assay,ELISA)检测HEV抗体,采用Logistic回归分析戊型肝炎感染的危险因素.结果 参与调查的63名MSM对象中,14名抗HEV-IgG阳性,阳性率为22.2％.多因素分析显示,近6个月内发生肛交性行为( OR=1L.924,95％ CI:1.783 ～79.730)、男男同性恋(OR=7.401,95％ CI:1.231～44.481)、职业为工人和农民(OR=8.131,95％CI=1.383-47.813)是HEV感染的危险因素.结论 MSM人群的高危性行为可能是戊型肝炎传播的危险因素.     

A bacterially expressed peptide prevents experimental infection of primates by the hepatitis E virus

A 23 kDa peptide of the major structural protein of the hepatitis E virus (HEV) expressed in E. coli was found to naturally interact with one another to form homodimers and the peptide was recognized strongly in its dimeric form by HEV reactive human sera. To determine if the peptide may confer protection against HEV infection, three monkeys were immunized with the purified peptide and three were given placebo. Both groups of animals were challenged with 10(5) genome equivalent dose of the homologous strain of HEV. All control animals excreted the virus for 10-12 days beginning 5 days after the infection. The viral genome was also present in the peripheral blood monocyte (PBMC) samples from two animals, but it was not detected in the plasma samples from any of the animals. The infection in two control animals was accompanied by HEV seroconversion. Immunization was found to abrogate HEV stool excretion in two animals and reduced the viral excretion to one day in the third. None of the immunized animals showed detectable HEV in plasma or PBMC samples nor did the animals showed evidence of HEV seroconversion. These results suggested that immunization with the bacterially expressed peptide may prevent experimental infection of primates with the homologous strain of HEV.     

Immunization with recombinant ORF2 p551 protein protects common marmosets (Callithrix jacchus) against homologous and heterologous hepatitis E virus challenge

BackgroundHepatitis E virus (HEV) is a major causative agent of acute hepatitis worldwide, prompting continuous HEV vaccine efforts. Vaccine development is hampered by the lack of convenient animal models susceptible to infection with different HEV genotypes. We produced recombinant open reading frame 2 protein (pORF2; p551) of HEV genotype (GT) 3 and assessed its immunogenicity and protectivity against HEV challenge in common marmosets (Callithrix jacchus, CM).Methodsp551 with consensus sequence corresponding to amino acid residues 110–660 of HEV GT3 pORF2 was expressed in E. coli and purified by affinity chromatography. CMs were immunized intramuscularly with 20 μg of p551 VLPs with alum adjuvant (n = 4) or adjuvant alone (n = 2) at weeks 0, 3, 7 and 19. At week 27, p551-immunized and control animals were challenged with HEV GT1 or GT3 and thereafter longitudinally screened for markers of liver function, anti-HEV IgG and HEV RNA in feces and sera.ResultsPurified p551 formed VLPs with particle size of 27.71 ± 2.42 nm. Two immunizations with p551 induced anti-HEV IgG mean titer of 1:1810. Immunized CMs challenged with homologous and heterologous HEV genotype did not develop HEV infection during the follow-up. Control CMs infected with both HEV GT1 and GT3 demonstrated signs of HEV infection with virus shedding and elevation of the levels of liver enzymes. High levels of anti-HEV IgG persisted in vaccinated CMs and control CMs that resolved HEV infection, for up to two years post challenge.ConclusionsCMs are shown to be a convenient laboratory animal model susceptible to infection with HEV GT1 and GT3. Immunization with HEV GT3 ORF2/p551 triggers potent anti-HEV antibody response protecting CMs from homologous and heterologous HEV challenge. This advances p551 in VLPs as a prototype vaccine against HEV.     

Hepatitis E vaccine immunization for rabbits to prevent animal HEV infection and zoonotic transmission

Hepatitis E virus (HEV) infection has become a significant global public health concern as increasing cases of acute and chronic hepatitis E are reported. HEV of animal origin was proved to be a possible source of human infection and a previous study showed that the recent licensed HEV 239 vaccine can serve as a candidate vaccine to manage animal sources of HEV infection. However, previous immunization strategy for rabbits was the same as that for human, which is too costly to conduct large-scale animal vaccination. In an effort to reduce the costs, three vaccination schemes were assessed in the present study. Forty specific pathogen-free (SPF) rabbits were divided randomly into five groups with eight animals for each and inoculated intramuscularly with different doses of HEV 239 and placebo, respectively. All animals were challenged intravenously with swine HEV-4 and rabbit HEV of different titers 7 weeks after the initial immunization and then fecal virus excretion was monitored for 10 weeks. The results indicated that immunizing rabbits with two 10 μg doses of the vaccine is superior to vaccination with two 20 μg doses or a single 30 μg dose, which can protect rabbits against homologous and heterologous HEV infection. These findings could enable implementation of large-scale animal vaccination to prevent rabbit HEV infection and zoonotic transmission.     

Protection of cynomolgus monkeys against HEV infection by oral administration of recombinant hepatitis E virus-like particles

Hepatitis E virus (HEV) is an important causative agent of enterically-transmitted hepatitis. Successful vaccine development is crucial in controlling global HEV infection. HEV capsid protein, with 111 amino acids truncated at the N-terminus, was efficiently expressed in the baculovirus expression system. Expressed protein spontaneously assembled into virus-like particles (VLPs) and was released into culture medium. When cynomolgus monkeys were orally inoculated with 10mg of purified rHEV VLPs, serum IgM, IgG, and IgA responses were observed. All these antibody responses were obtained without adjuvants. When the monkeys were challenged with native HEV by intravenous injection, they were protected against infection or developing hepatitis. These results suggested that recombinant HEV (rHEV) VLPs can be a candidate for the oral hepatitis E vaccine.     

Hepatitis E virus infection without reactivation in solid-organ transplant recipients, France

Infections with hepatitis E virus (HEV) in solid-organ transplant recipients can lead to chronic hepatitis. However, the incidence of de novo HEV infections after transplantation and risk for reactivation in patients with antibodies against HEV before transplantation are unknown. Pretransplant prevalence of these antibodies in 700 solid-organ transplant recipients at Toulouse University Hospital in France was 14.1%. We found no HEV reactivation among patients with antibodies against HEV at the first annual checkup or by measuring liver enzyme activities and HEV RNA. In contrast, we found 34 locally acquired HEV infections among patients with no antibodies against HEV, 47% of whom had a chronic infection, resulting in an incidence of 3.2/100 person-years. Independent risk factors for HEV infection were an age <52 years at transplantation and receiving a liver transplant. Effective prophylactic measures that include those for potential zoonotic infections should reduce the risk for HEV transmission in this population.     

戊型肝炎病毒感染动物模型应用于抗-HEV试剂评价的初步研究

目的应用实验室戊型肝炎病毒（HEV）感染恒河猴动物模型对抗-HEV诊断试剂进行初步的评价。方法用1和4基因型的HEV静脉注射分别感染4只恒河猴，检测实验猴的丙氨酸氨基转移酶（ALT）水平，逆转录聚合酶链反应（RT-PCR）方法检测粪便标本中HEVRNA，抗-HEVIgG试剂（GL-IgG，wT-IgG）分别检测实验猴系列血清抗体水平。结果HEV感染的8只实验猴均出现粪便排毒，1和4基因型HEV感染的实验猴分别有1只和2只出现ALT升高，GL-IgG试剂检测1型HEV实验感染猴有2只抗体阳转，4型HEV实验感染猴有1只抗体阳转；而wT-IgG试剂检测1、4型HEV实验感染猴的抗体均阳转。两种试剂检测感染猴窗口期抗体阳转时间相近，GL-IgG试剂抗体阳性持续到12周，wrT-IgG试剂在16周观察期内均阳性。结论两种试剂均可检测出感染实验猴的抗体，但wT-IgG试剂具有检测灵敏度较高的特点。     

戊型肝炎病毒ORF3蛋白功能的研究进展

戊型肝炎是一种由戊型肝炎病毒(HEV)引起的经肠道传播的病毒性肝炎。对HEV结构蛋白的深入研究有利于病毒感染机制的明确和疾病的预防。ORF3蛋白作为HEV结构蛋白之一,其具体功能目前仍不太清楚。一直以来,针对该蛋白的研究非常少,近年来研究发现HEV ORF3蛋白在细胞信号转导、病毒感染和免疫抑制等方面都有非常重要的作用。     

Infection dynamics of hepatitis E virus in naturally infected pigs in a Chinese farrow-to-finish farm

To analyze the changes that occur in pigs during hepatitis E virus (HEV) infection, 256 serial serum samples were obtained from 32 pigs from one pig farm at ages 0 (cord blood), 15, 30, 60, 75, 90, 120, and 150 days. All HEV markers were assayed in these samples and showed that total anti-HEV antibodies and IgG formed two peaks. The first peak occurred at 0–60 days and the second after 75 days. No markers of infection, such as HEV RNA, antigen and anti-HEV IgM, were detectable during the first peak. Most newborn piglets (<24 h of age) were negative for total anti-HEV and IgG. However, colostrum from all of the sows had evidence of these antibodies. Thus, the anti-HEV in the first peak was assumed to be acquired from maternal milk. Some infectious markers were positive at the beginning of second peak. PCR products were cloned and sequenced and the results indicated those sequences belonged to HEV genotype 4. The antibody present during the second peak may be induced by natural infection with HEV. In conclusion, pigs are susceptible to HEV infection and may remain infectious after the first peak of anti-HEV antibody.     

Human and porcine hepatitis E virus strains, United Kingdom

We describe a case of acquired infection of a strain of hepatitis E virus (HEV) with a 100% amino acid identity to the analogous region in strains of HEV circulating in a United Kingdom pig herd. This case further supports the theory that autochthonous HEV infection in industrialized countries is zoonotic.     

天津市食品和公共场所从业人群HEV亚临床感染的流行趋势

目的了解天津市食品和公共场所从业人群中戊型肝炎病毒（HEV）亚临床感染的流行趋势,旨在为戊型病毒性肝炎（戊肝）的预防和控制工作提供科学依据。方法对2010年3月—2012年12月期间在天津市疾病预防控制中心预防医学门诊部进行预防性健康检查者的资料进行统计分析,采用圆形分布法推算HEV亚临床感染的季节性特征。结果天津市食物和公共场所从业人群HEV亚临床感染存在一定的季节高峰（r=0．2270,P〈0．01）;此高峰平缓,高峰日为8月19日,高峰期为5月11日-11月28日。3年共检出HEV-IgM阳性者115人,HEV亚临床感染率为0．45％。食品行业从业人员HEV亚临床感染率明显高于公共场所,差异有统计学意义（x^2=6．511,P〈0．05）。结论天津市食品和公共场所从业人群HEV亚临床感染具有一定的季节性特征,并与受检者行业类别具有较为明显的相关性。因此,今后防控工作的重点应放在5-11月,采取综合性措施加大对食品行业从业人员HEV感染的防控力度,有效控制传染源,保护广大市民的身体健康。     

慢性病毒性乙型肝炎合并戊型肝炎病毒感染的临床及实验指标变化

目的 比较慢性病毒性乙型肝炎和其重叠戊型肝炎病毒(HEV)感染的临床特点，乙型肝炎病毒(HBV)复制指标，以及肝功能方面是否存在差异；了解HEV感染对HBV复制的影响。方法 应用酶联免疫吸附试验和聚合酶链反应分别检测HBV组和HBV HEV组中的乙型肝炎两对半，抗-HBc IgG，抗-HBc IgM，HBV DNA，抗-HEV IgM。结果 重叠HEV感染较单纯HBV感染病情重，肝功能损害明显；100例HBV重叠HEV感染者的HBV DNA和乙型肝炎e抗原(HBeAg)阳性率分别为36％和23％，100例单纯HBV感染者的HBV DNA和HBeAg阳性率分别为86％和60％。结论 重叠HEV感染可加重HBV感染者的病情，并能抑制HBV复制。