戊型肝炎流行病学研究进展

戊型肝炎是一种经粪-口途径传播的急性病毒性肝炎,可经水、食物等途径传播引起散发或暴发流行,发病以青壮年为主,孕妇易发生急性肝功能衰竭导致死亡率较高,已成为全球性重要公共卫生问题之一。本文对戊型肝炎的流行特征、传染源、传播途径、人群易感性的研究进展和存在的问题进行综述。     

戊型肝炎研究进展

戊型肝炎研究进展朱晓洁，庄辉既往所称肠道传播的非甲非乙型肝炎，１９８９年被正式命名为戊型肝炎（ＨＥ）。本文综述了ＨＥ病原学、流行病学、临床、实验室诊断、动物模型和体外细胞培养等方面的研究进展。一、病原学１９８３年Ｂａｌａｙａｎ等￣［１］应用免疫电镜（...     

戊型肝炎研究进展

戊型肝炎既往称为肠道传播的非甲非乙型肝炎。世界上首次有记载的本病流行系发生于1955～1956年新德里,共计发病97000例,其中29300例为黄疽型肝炎。1980年Khuroo等报告,1978年11月～1979年4月克什米尔流域发生本病流行。1983年Balayan等首次用成型肝炎病人粪便经口感染一名志愿者获得成功,并从急性期粪便中用免疫电镜检测到     

戊型肝炎疫苗研究进展

戊型肝炎(戊肝)病毒(HEV)经粪-口途径传播,有嗜肝性,发病时表现为急性肝炎.在亚洲及非洲发展中国家均有传播,中国亦有分布.在发达国家,HEV主要影响猪和禽的养殖,密切接触生猪及鲜猪肉的人群中,抗-HEV抗体阳性率较高.虽然在发达国家仅有零星病例,但是普通人群中抗体阳性率比预期要高[1].在中亚和东南亚,HEV是急性临床型肝炎病例最主要的病原体,而在中非、东非和北非,HEV是造成肝病的第二位原因(仅次于HBV)[1].HEV感染的病死率为1%～4%[1],孕妇感染后病死率可高达20%[1,2].HEV分5个基因型,其中1、2型感染人类,3、4型可感染人和猪,5型感染鸟类[1].     

戊型肝炎病原学研究进展

本文重点介绍近年来戊型肝炎病原学的研究进展，就其理化性状，基因结构和亚型作简要综述。     

戊型肝炎疫苗的研究进展

自 1991年戊型肝炎病毒 (ＨＥＶ)基因组全序列被克隆和测序后 ,对ＨＥＶ的致病性、分子生物学及疫苗进行了深入研究。但近年来发现 ,ＨＥＶ的流行范围远较最初预料的要广泛 ,从而给ＨＥＶ疫苗研究提出了新问题。一、ＨＥＶ基因型和血清型目前 ,已知人ＨＥＶ基因型有 8型 ,即Ⅰ型以缅甸株为代表 ,Ⅱ型以墨西哥株为代表 ,Ⅲ型为美国株ＵＳ 1和ＵＳ 2 ,Ⅳ型为中国株 ,Ⅴ～Ⅶ型为欧洲分离株 ,Ⅷ型为美洲另一分离株[1] 。除人ＨＥＶ以外 ,尚有猪ＨＥＶ ,由美国最早发现 ,其与Ⅲ型美国株ＨＥＶ亲缘关系较近。实验结果表明 ,猪ＨＥＶ可感染灵长类动…     

戊型肝炎血清抗体的研究进展

本文介绍了近年来戊型肝炎血清抗体的研究近况，主要就ＩｇＡ，ＩｇＭ，ＩｇＧ抗－ＨＥＶ的消长规律，戊型肝炎血清抗体在判断病程经过，鉴别诊断，评价保护性免疫力及疫苗研制等方面的重要作用作了简述。     

慢性戊型肝炎相关研究进展

戊型肝炎散发于世界各地,多为急性自限性疾病,但近年来不断有文献报道在HIV感染者、器官移植和放化疗患者等免疫力低下人群中发现基因3型戊型肝炎病毒感染导致的戊型肝炎慢性化疾病,其临床表现类似急性戊型肝炎,但症状及肝功能损伤均较轻.目前研究发现,人群感染戊型肝炎病毒后肝炎慢性化的机制主要包括宿主因素和病毒因素.此文就慢性戊型肝炎的定义、临床表现、患者特征、感染慢性化的病毒因素及治疗等方面的进展进行综述.     

Hepatitis E virus transmission from wild boar meat

We investigated a case of hepatitis E acquired after persons ate wild boar meat. Genotype 3 hepatitis E virus (HEV) RNA was detected in both patient serum and wild boar meat. These findings provided direct evidence of zoonotic foodborne transmission of HEV from a wild boar to a human.     

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.     

马鞍山市既往有偿献血人员戊型肝炎检测分析

目的了解马鞍山市既往有偿献血人员中戊型肝炎感染状况,为此类传染病防治提供依据。方法采集有偿献血人员及农村正常人群的血清,通过酶联免疫吸附试验检测血清中戊型肝炎病毒的IgG抗体。结果共检测标本992例,其中既往有偿献血人员492例,检测出抗HEV-IgG抗体阳性病例数126例,阳性率25.6%;正常农村人群500例,检测出40例阳性,阳性率8%。结论既往有偿献血人员戊型肝炎感染率显著高于一般人群,戊型肝炎经血传播的危险是一个客观存在和值得关注的问题。     

Hepatitis E Virus Antibodies in Patients with Chronic Liver Disease

In the United States, the seroprevalence rate for hepatitis E virus (HEV) is ≈20%. This study examined HEV seroprevalence in persons with and without chronic liver disease. Our data indicate that HEV seropositivity is high in patients with chronic liver disease and that HEV seroprevalence increases significantly with age.     

Hepatitis E virus

Hepatitis E virus (HEV) is responsible for major outbreaks of acute hepatitis in developing countries where it was first described as a waterborne disease, transmitted by drinking water contaminated with feces. Attention was focused on HEV in developed countries and its associated diseases in recent years as a result of increasing reports of autochthonous infections. Hepatitis E is the zoonotic cause of these acute infections, and mainly in men over 50 years of age. The clinical manifestations and laboratory abnormalities of hepatitis E infections in immunocompetent patients cannot be distinguished from those caused by other hepatitis viruses. HEV is a major public health concern in immunocompromised patients because their infections can become chronic. The specific etiology of cases of hepatitis E infection can be diagnosed by serological testing and detecting viral RNA. Ribavirin is currently the reference treatment for HEV infections in immunocompromised patients. Several vaccines have proved safe and effective in clinical trials, but none have been approved for use in Europe yet.     

Hepatitis E: An emerging disease

Currently, the infection with the hepatitis E virus represents the most frequent cause for acute hepatitis and jaundice in the world. According to WHO estimations, around two billion people, representing one third of the world’s population, live in endemic areas for HEV and, therefore, are at risk of infection. In developed countries, the circulation of the virus in both human and animal (swine, boar, deer) sewage has been confirmed; however, the incidence rate is low compared to that of developing countries where outbreaks of acute hepatitis transmitted via the fecal-oral route are originated, more frequently in the flooding season or after natural disasters, combined with deficient sanitary conditions.There are currently 4 known genotypes of HEV. Genotypes 1 and 2 are isolated in all human epidemic outbreaks in developing countries, while genotypes 3 and 4 are isolated not only in humans but also in animals, in both developing and industrialized countries. These data support genotypes 3 and 4 having zoonotic nature. The diagnosis of this disease is based in the detection of anti-HEV IgG and IgM in blood serum using enzyme-linked immunosorbent methods. However, the method that best confirms the diagnosis is the RT-PCR, which detects HEV RNA in blood serum and also provides the genotype. The clinical course is generally that of an acute hepatitis which in some cases may require hospitalization and that, in transplant patients or HIV infected individuals can become a chronic hepatitis. Furthermore, the virus constitutes an important risk for pregnant women. The hepatitis E can present a wide range of symptoms, from a subclinical case to chronic liver disease with extrahepatic manifestations. For this reason, the diagnostic is challenging if no differential diagnosis is included. There is no specific antiviral drug for hepatitis E, but satisfactory results have been observed in some patients treated with pegylated interferon alfa2a and/or ribavirin.This revision is an update of all the molecular, epidemiological, clinic and preventive knowledge on this emergent disease up to date.     

戊型病毒性肝炎研究进展

戊型病毒性肝炎（戊肝）约占临床急性散发性病毒性肝炎的10%～20%,病死率约0.5%～1.5%,孕妇戊肝病人的病死率可高达20%。中国是戊肝的高流行区。戊肝病毒主要通过肠道传播,亦有证据表明可以通过血液传播。近年来,随着对戊肝病原学、流行病学研究的深入开展,诊断试剂及疫苗研发进展迅速,现对戊肝的流行病学、诊断学及疫苗研究作一综述。     

Sources of Hepatitis E Virus Genotype 3 in the Netherlands

Non–travel-related hepatitis E virus (HEV) genotype 3 infections in persons in the Netherlands may have a zoonotic, foodborne, or water-borne origin. Possible reservoirs for HEV transmission by water, food, and animals were studied. HEV genotype 3/open reading frame 2 sequences were detected in 53% of pig farms, 4% of wild boar feces, and 17% of surface water samples. HEV sequences grouped within 4 genotype 3 clusters, of which 1 is so far unique to the Netherlands. The 2 largest clusters contained 35% and 43% of the animal and environmental sequences and 75% and 6%, respectively, of human HEV sequences obtained from a study on Dutch hepatitis E patients. This finding suggests that infection risk may be also dependent on transmission routes other than the ones currently studied. Besides the route of exposure, virus characteristics may be an important determinant for HEV disease in humans.     

Possible zoonotic transmission of hepatitis E from pet pig to its owner

Hepatitis E is transmitted mainly by water or food, but in industrialized countries, all routes of transmission have not been identified. We describe possible zoonotic transmission of hepatitis E virus that involved direct contact between a pet pig and its owner.