四川地区部分人群和与人接触密切的家畜禽戊型肝炎病毒感染的调查及基因分型的研究

目的 了解四川地区人群和与人接触密切的家畜猪和鸡戊型肝炎(戊肝)病毒感染的分布及病毒基因分析.方法 采用万泰生物药业的HEV EIA诊断试剂检测人群、猪和鸡血清中戊肝病毒(HEV)IgG抗体.采用逆转录套式PCR方法(RT-nPCR)检测猪胆汁和血清中戊肝病毒核酸,并对阳性产物进行纯化和部分核苷酸序列分析.结果 学龄前儿童血清672份中有41份阳性,阳性率6.1%,成人血清661份中有280例阳性,阳性率42.36%,猪血清36份中有32份阳性,阳性率为88.89%,59份鸡血清HEV抗体均阴性.对15份HEV IgM抗体阳性的患者血清和54份猪胆汁进行RT-nPCR,从1份患者血清和3份猪胆汁扩增到戊肝病毒核酸,4株核苷酸序列之间同源性92.1%～98.6%,与GenBank HEV参考株ORF2相对应序列比较,核苷酸序列与Ch-T21(我国散发性急性肝炎人分离株HEV4 B亚型)之间同源性最高占90.1%～96.9%.结论 四川地区部分人群和与人接触密切的家畜猪均存在HEV感染,尤其是家畜猪感染率高达90%左右,从人和猪分离到的病毒株核苷酸同源性很高,均属于戊肝病毒基因4型.     

我国汉、回和藏族部分人群HEV感染的血清学调查

目的 了解我国不同民族的健康人群戊型肝炎病毒感染情况.方法 采用ELISA方法检测人群血清中戊型肝炎病毒(戊肝,HEV)IgG抗体.汉族人群血清分别来自于四川、北京、黑龙江和山东,回族和藏族人群血清来自于甘肃、宁夏和青海,总共10 448份血清采集于2006 -2008年.结果 七省市人群HEV抗体总阳性率为17.97％(1878/10 448).汉、回和藏不同民族人群HEV抗体阳性率分别为24.32％ (1794/7376)、3.59％(81/2258)和0.37％(3/814).不同地区人群HEV抗体阳性率分布,四川、北京、黑龙江和山东汉族人群阳性率分别为27.45％、20.30％、22.89％和22.68％,甘肃汉和回族分别为24.63％( 184/747)和6.12％( 77/1258),宁夏回族和青海藏族分别0.40％和0.37％.汉回藏不同民族各年龄组人群HEV感染分布,汉族各年龄组人群HEV抗体阳性率,在≤10岁年龄组为5.19％,11～20岁组为11.64％,21 ～ 30岁组为20.08％,31 ～ 40岁组为34.17％,41 ～50岁为41.75％,51 ～60岁组为48.58％,≥61岁组为57.43％.回族人群各年龄组人群HEV抗体阳性率依次为3.11％,3.96％,2.11％,3.98％,2.52％,4.57％和6.67％.藏族人群3份阳性者分布在21～30岁组、31 ～40岁组和51 ～60岁组各1份,阳性率为0.63％、0.58％和1.01％.结论 汉族人群戊肝病毒感染明显高于回族和藏族,感染率随年龄增长而升高.回藏族人群HEV抗体阳性率低下,应加强对HEV感染的监测.     

甘肃省部分人群甲、乙、丙和戊型肝炎感染的血清学调查

目的 了解健康人群肝炎病毒感染现状.方法 采用ELISA方法检测人群血清中抗甲(HAV-IgG)、乙(HBsAg和HBsAb)、丙(HCV-IgG)和戊型肝炎病毒抗体(HEV-IgG).1977份人群血清收集于2008年5-10月.结果 人群肝炎病毒抗体阳性率,HAV-IgG为84.57%(1672/1977),HBsAS和HBsAb为4.81%(95/1977)和28.73%(568/1977),HCV-IgG为0.46%(9/1977),HEV-IgG为13.10%(259/1977).不同年龄段的人群肝炎病毒抗体阳性率分布,HAV-IgG阳性率,在≤9岁组至≥60岁组为43.21%～95.56%.HBsAg和HBsAb阳性率为2.09%～36.43%.HCV-IgG阳性总数9份,分布在30～59岁年龄组阳性为0.59%～1.79%.HEV-IgG阳性率,≤9岁组至≥3岁组分别为3.48%～21.67%.结论 低年龄组人群HAV和HBsAb抗体明显低于人群总体水平,应及时加强免疫预防.HBsAg携带和HCV感染下降.HEV感染随年龄增长而升高,汉和回族人群HEV感染率存在明显差别.     

我国戊型肝炎ELISA诊断试剂的质量比较

目的对戊型肝炎(戊肝)诊断试剂进行质量评价。方法选择北京万泰生物药业(万泰),北京现代高达生物技术(高达),上海科华生物工程(科华),GeneLabs Diagnostic Inc(GeneLabs),和河南华美生物工程(华美)共5家公司生产的检测戊肝病毒IgG(HEV-IgG)抗体的ELISA试剂,分别检测戊肝诊断试剂参比品、可疑戊肝临床患者和正常人群血清HEV抗体。结果对24份阳性和30份阴性参比品检测,以万泰试剂检测符合率最高,阳性和阴性符合率分别为95.83%(23/24)和96.67%(29/30),总符合率为96.30%,其次为高达试剂87.50%(21/24)和100%(30/30),总符合率为94.44%,华美试剂87.50%(21/24)和96.67%(29/30),总符合率92.59%,GeneLabs66.67%(16/24)和100%(30/30),总符合率为85.18%,科华试剂45.83%(11/24)和100%(30/30),总符合率为75.93%。对42份可疑戊肝患者血清HEV抗体检测阳性率,高达试剂为100%(42),万泰和华美试剂均为97.62%(41),GeneLabs和科华试剂均为90.48%(38)。对230份正常人群HEV抗体检测阳性率,从高到低依次为万泰试剂31.74%(73),华美试剂为23.91%(55),高达试剂为17.39%(40),GeneLabs和科华试剂分别是7.83%(18)和3.48%(8)。结论5家试剂检测急性期戊肝患者抗体阳性率均能达90%以上,具有很高的一致率,而应用于普通人群HEV感染的调查,其抗体阳性率从31.74%~3.48%不等。不同的试剂存在假阳性或和阳性漏检现象。依本室参比品和人群血清阳性率来看,万泰试剂检出率较高。     

烟台沿海地区人源和猪源戊型肝炎病毒基因型别的研究

目的 调查烟台市沿海地区人源与猪源戊型肝炎病毒(HEV)基因型别的相关性.方法 应用逆转录一巢式聚合酶联反应( RT-nPCR)方法对当地急性散发戊型肝炎患者、正常人群中抗HEV-IgM阳性者和当地养猪场的猪进行HEV RNA检测,并对HEV RNA阳性标本进行克隆测序和序列分析.结果 16例急性散发戊型肝炎患者中有7例粪便标本HEV RNA阳性;51份lgM阳性正常人群血清标本中有1份HEV RNA阳性;34份猪胆汁标本中有1份HEV RNA阳性.序列分析发现该地区HEV人株与猪株在ORF2部分区域的核苷酸序列同源性为87％～ 98.1％.7株患者的戊肝病毒基因型和1株猪的戊肝病毒基因型均为Ⅳ型,基因序列同源性在87％ ～ 98.1％之间;其中有6例患者和猪的基因序列同源性在93.9％ ～98.1％之间,为Ⅳ型a亚型;1例患者和猪的基因序列同源性为87％,为Ⅳ型d亚型.正常人群的1例戊肝病毒基因型为Ⅰ型d亚型.该地区人与猪HEV的ORF2的部分基因片段与HEV Ⅰ～Ⅳ型的代表株进行比较,核苷酸序列同源性分别是82.5％～100％,81.7％ ～92.9％,81.4％ ～93.9％,84.9％ ～ 100％.结论 该地区人群中流行的HEV存在2个基因型3个亚型,主要以基因Ⅳa型为主,与猪群中流行的HEV基因Ⅳa型同源性较高;HEV Ⅰ型在人群中散在存在.     

四川绵阳部分人群甲、乙、丙和戊型肝炎病毒感染血清学调查

目的 了解健康人群肝炎病毒感染现状.方法 采用ELISA方法检测体检人群血清中抗甲(HAV-IgG)、乙(HBsAg和HBsAb)、丙(HCV-IgG)和戊型肝炎病毒抗体(HEV-IgG和IgM).人群血清均收集于2007年.结果 1352份人群血清肝炎病毒抗体阳性率,HAV-IgG为81,07%(1096/1352),HBsAg和HBsAb为5.4%(73/1352)和61.32%(829/1352),HCV-IgG为0.37%(5/1352),HEV-IgG为49.26%(666/1352).不同年龄段的人群HAV-IgG阳性率,10～19岁组为38.21%,20～29岁组为83%,30～39岁组为88%,40岁以上各年龄组为95.03%～97.77%.HBsAg和HBsAb阳性率,各年龄组依次为5.65%和50.83%、10.0%和68.0%、5.20%和78.80%、5.97%和78.11%、6.50%和62.50%、1.12%和51.40%、4.96%和30.58%.HCV-IgG阳性总数5份,其中10～19岁组1份,阳性率占0.33%,30～39岁组2份,占0.80%,60～69岁1份占0.56%,≥70岁1份占0.83%.HEV-IgG阳性率,10～19岁为26.58%,20～29岁组为42.0%,30岁以上各年龄组阳性率为55.22%～61.0%.对HEV-IgG阳性者再检测HEV-IgG,总阳性率为10.06%(53/527),各年龄组均有阳性者.结论 青少年HAV和HBsAb抗体低于人群总体水平,应及时加强免疫预防.人群HBsAg和HCV感染率与往年相比下降明显.HEV感染率随年龄增长而升高,特别是各年龄段均有新近感染者,应加强餐饮和公共卫生管理.     

我国汉、回和藏族部分人群HEV感染的血清学调查

目的了解我国不同民族的健康人群戊型肝炎病毒感染情况。方法采用ELISA方法检测人群血清中戊型肝炎病毒（戊肝,HEV）IgG抗体。汉族人群血清分别来自于四川、北京、黑龙江和山东,回族和藏族人群血清来自于甘肃、宁夏和青海,总共10448份血清采集于2006—2008年。结果七省市人群HEV抗体总阳性率为17．97％（1878／10448）。汉、回和藏不同民族人群HEV抗体阳性率分别为24．32％（1794／7376）、3．59％（81／2258）和0．37％（3／814）。不同地区人群HEV抗体阳性率分布,四川、北京、黑龙江和山东汉族人群阳性率分别为27．45％、20．30％、22．89％和22．68％,甘肃汉和回族分别为24．63％（184／747）和6．12％（77／1258）,宁夏回族和青海藏族分别0．40％和0．37％。汉回藏不同民族各年龄组人群HEV感染分布,汉族各年龄组人群HEV抗体阳性率,在≤10岁年龄组为5．19％,11～20岁组为11．64％,21～30岁组为20．08％,31～40岁组为34．17％,41—50岁为41．75％,51～60岁组为48．58％,≥61岁组为57．43％。回族人群各年龄组人群HEV抗体阳性率依次为3．11％,3．96％,2．11％,3．98％,2．52％,4．57％和6．67％。藏族人群3份阳性者分布在21—30岁组、31—40岁组和51～60岁组各1份,阳性率为0．63％、0．58％和1．01％。结论汉族人群戊肝病毒感染明显高于回族和藏族,感染率随年龄增长而升高。回藏族人群HEV抗体阳性率低下,应加强对HEV感染的监测。     

北京地区猪养殖和屠宰职业人群戊肝感染现况研究

目的 了解北京地区猪养殖和屠宰职业人群戊肝感染现状.方法 北京市5个区264名养殖和屠宰职业人群被选作调查对象,采用标准化问卷进行问卷调查,采静脉血进行戊肝抗体检测,比较猪养殖和屠宰职业人群戊肝感染现状.结果 戊肝总感染率为38.396.男女戊肝感染率分别为40.2%和34.4%.年龄分布中以30～40岁年龄组戊肝感染率最高为51.3%.职业分布中以养殖场饲养员戊肝感染率为57.6 96,显著高于其他各职业人群.结论 猪养殖和屠宰职业人群戊肝感染率较高,养殖场饲养员是戊肝感染的高危群体.     

河南地区不同月龄猪戊型肝炎病毒感染情况调查

目的 调查河南地区不同月龄猪戊型肝炎病毒(HEV)感染情况.方法 从河南五个地区共采集623份猪血清,其中3月龄以下血清113份,3月龄以上血清510份,酶联免疫诊断试剂盒分别检测HEV抗原和抗体.对抗原阳性者用套式RT-PCR检测HEV核酸,并对核酸阳性者进行克隆和序列分析.结果 3月以下组和3月以上组的抗体阳性率分别为90.27%和92.55%,差异无统计学;而两组的抗原阳性率分别为15.93%和5.69%,差异有统计学意义(P＜0.001).各地区间的抗原和抗体阳性率存在明显的统计学差异.在47份抗原阳性样本中,检出5例为HEV核酸阳性,序列分析显示4例为HEV4型,1例为HEV 1型.结论 河南地区猪的HEV感染率较高,而且不同地区存在明显差异.     

我国六省市(区)部分人群丙型肝炎病毒感染调查

目的 了解我国健康人群丙型肝炎病毒感染现状.方法 采用北京万泰生物药业的HCV EIA诊断试剂检测人群血清丙型肝炎病毒(丙肝,HCV)IgG抗体.结果 六省市(区)人群血清共9 538份,HCV抗体阳性数37份,总阳性率为0.39％,其中北京人群阳性率0.23％,黑龙江人群为0.74％,山东人群为0.26％,宁夏人群为0.10％,甘肃和四川人群阳性率均为0.44％.对37例HCV阳性者性别及年龄分析,男性19例占51.35％,女性18例占48.65％,＜10岁年龄组1例,占2.70％,10～19岁组5例,占13.51％,20～29岁4例占10.81％,30～39岁组6例,占16.22％,40～49岁组9例,占24.32％,≥50岁有12例占32.43％.对HCV阳性者重叠其他型别肝炎病毒感染分析,单独HCV阳性2例,占5.41％,伴有HAV-IgG抗体阳性35例,占94.59％,伴有HEV-IgG抗体阳性10例,占27.03％,伴有HBsAg、HBcAb和HbeAb阳性者2例,占5.41％,该2例HAV和HEV抗体也阳性.结论 六省市(区)人群HCV感染率均在1％以下,感染者年龄以50岁以上最高,决大多数HCV阳性者重叠有其他型别的肝炎病毒感染.     

猪、羊、鸡抗-HEV抗体流行率调查

目的 探讨猪、羊、鸡群中抗-HEV抗体流行率。方法从新疆、广西、广东、北京和河北收集猪、羊、鸡的血清标本498份，应用双抗原夹心酶联免疫法(ELISA)检测抗-HEV抗体。结果 猪抗-HEV阳性率为67．53％(104／154)，其中新疆4～5个月龄猪血清抗-HEV阳性率为100．00％，广西3个月龄以下仔猪抗-HEV阳性率为36．00％(9／25)，6月龄以上猪阳性率为71．67％(86／120)；新疆108份绵羊血清抗-HEV抗体全部阴性；236份鸡血清标本的抗-HEV阳性率仅为1．27％(3／236)。广东罗定、深圳和广西柳州郊区鸡血清标本中各检测出一份抗-HEV阳性，阳性率分别为4．00％(1／25)、1．49％(1／67)、1．49％(1／67)。北京郊区25份和河北52份鸡血清抗-HEV检测全部阴性。结论 猪、鸡群中存在HEV感染，猪抗-HEV抗体流行率最高。猪和鸡在传播人HEV中的作用值得进一步研究。     

无偿献血人群戊型肝炎病毒感染情况调查

目的调查绍兴市街头无偿献血者戊型肝炎病毒感染情况。方法3701例无偿献血者标本采用ELISA方法检测抗-HEV IgG和抗-HEV IgM,RT-PCR检测抗-HEV IgM阳性血清HEV RNA。结果本市无偿献血者抗-HEV IgG阳性率为29.91%(1107/3701);抗-HEVIgM阳性率为1.35%(50/3701);HEV RNA阳性6例,检出率为0.16%(6/3701),均为HEV基因1型;各季节抗-HEV IgG和抗-HEV IgM的阳性检出率无显著差异。结论加强对献血者感染HEV情况的检测和研究,对保证用血安全,完善安全输血的保障体系有切实的意义。     

Clinical and epidemiological implications of swine hepatitis E virus infection

In nonendemic areas, most patients with acute hepatitis E were infected through traveling to endemic areas. However, some patients did not have a history of foreign travel before infection. Furthermore, high seroprevalence rates of antibody to hepatitis E virus (anti-HEV) were found in the general adult population in some countries without any recorded outbreak of hepatitis E. The significance of anti-HEV assay in these subjects remains obscure. To study if swine might be a source of HEV infection, HEV was tested in sera of 235 pigs in Taiwan, and from 5 patients with acute HEV infection who either denied or did not provide any foreign travel history. Three (1.3%) pigs had detectable swine HEV RNA. The swine and human HEV strains from Taiwan formed a monophyletic group, distinct from three previously reported groups: the United States human and swine HEV strains, the Mexico strain, and the largest group composed of the Asian and the African strains. The identity of nucleotide sequences was 84-95% between swine and human HEV strains in Taiwan, and 72-79% between Taiwan strains and those from different areas. The predicted amino acid sequence of a Taiwan swine HEV strain within the peptide 3-2 used in commercial anti-HEV assay showed a high identity (91-94%) with those of other human and swine HEV strains. Swine may be a reservoir of HEV and subclinical swine HEV infection may occur. Cross-reactivity of current anti-HEV assay may account for the high prevalence rate of anti-HEV in the general population in nonendemic areas.     

Prevalence of hepatitis E virus among swine and humans in two different ethnic communities in Indonesia

The purpose of this study was to investigate the prevalence of hepatitis E virus (HEV) infection in swine and humans in different environments in Java and Bali, Indonesia. The prevalence of anti-HEV antibodies in people over 20?years old living in communities in Bali was significantly higher than that in Java. While 68.8% and 90.0% of swine in Bali were anti-HEV positive at 1 and 2?months of age, respectively, swine in Java were at significantly lower risk of HEV infection by the age of 2?months. Our present data suggest that substantial differences in swine-breeding conditions and human living environments affect the rate of HEV infection in humans and swine.     

Differences in capabilities of different enzyme immunoassays to detect anti-hepatitis E virus immunoglobulin G in pigs infected experimentally with hepatitis E virus genotype 3 or 4 and in pigs with unknown exposure

Hepatitis E virus (HEV), a major cause of acute viral hepatitis in humans in many developing countries, is highly prevalent in the pig population worldwide. The objective of this study was to assess the capability of three porcine prototypes of a human enzyme-linked immunosorbent assay (ELISA), an in-house ELISA and a line-immunoassay (LIA) to detect anti-HEV antibodies in pigs infected experimentally with HEV (n = 57), known to be negative for HEV infection (n = 27), or with unknown exposure to HEV infection (field samples, n = 90). All 27 samples from non-infected pigs were negative with all five assays. The earliest detection of anti-HEV antibodies occurred at 14 days post-inoculation (dpi) with four of five assays. From 42 dpi, all samples from infected pigs were detected correctly as anti-HEV positive. Kappa analysis demonstrated substantial agreement among tests (0.62-1.00) at 14 dpi and complete agreement (1.00) at 56 dpi. The overall area under the curve for all quantitative tests as determined by receiver operator characteristic analysis ranged from 0.794 to 0.831 indicating moderate accuracy. The results showed that all five assays can detect anti-HEV IgG antibodies accurately in pigs infected experimentally with HEV. In field samples, a higher prevalence of anti-HEV IgG was found in breeding herds than in growing pigs (100% versus 66.7-93.9%). These serological assays should be very useful in veterinary diagnostic labs for HEV diagnosis in swine.     

衢州地区献血者戊型肝炎流行病学及其亚临床感染和病毒血症情况调查

目的 调查浙江衢州地区戊型肝炎的感染情况.方法 对2006年4月至2007年4月间衢州市中心血站的献血者进行整群抽样,检测抗HEV IgG以及IgM抗体,并对抗HEV IgM阳性的标本进行RT-PCR检测,经测序后分析其基因型及序列同源性.结果 4860例无偿献血者中,HEV IgG阳性率为40.62%,其中男性感染率显著高于女性感染率(43.09%vs.36.09%)(x2=22.6,P＜0.01).感染率随年龄的增长而升高.在抗HEV IgG抗体阳性者中,抗体滴度与年龄、性别并无显著相关性.IgM阳性率为0.43%,IgM阳性的亚临床感染者较IgM阴性的人群有较高的HEV IgG阳性率及抗体滴度(P＜0.05).21例IgM阳性者中发现2例HEV PCR阳性.献血者中病毒血症总阳性率为0.4‰.2例病毒血症者均为HEV Ⅳ型.结论 衢州地区戊型肝炎感染与年龄和性别显著相关,且感染主要发生在成年之后.在献血者中,HEV病毒血症并不罕见.     

Prevalence of Antibodies to Hepatitis E Virus in Veterinarians Working with Swine and in Normal Blood Donors in the United States and Other Countries

Hepatitis E virus (HEV) is endemic in many developing and some industrialized countries. It has been hypothesized that animals may be the source of infection. The recent identification of swine HEV in U.S. pigs and the demonstration of its ability to infect across species have lent credence to this hypothesis. To assess the potential risk of zoonotic HEV infection, we tested a total of 468 veterinarians working with swine (including 389 U.S. swine veterinarians) and 400 normal U.S. blood donors for immunoglobulin G anti-HEV. Recombinant capsid antigens from a U.S. strain of swine HEV and from a human HEV strain (Sar-55) were each used in an enzyme-linked immunosorbent assay. The anti-HEV prevalence assayed with the swine HEV antigen showed 97% concordance with that obtained with the human HEV antigen (kappa = 92%). Among the 295 swine veterinarians tested from the eight U.S. states (Minnesota, Indiana, Nebraska, Iowa, Illinois, Missouri, North Carolina, and Alabama) from which normal blood donor samples were available, 26% were positive with Sar-55 antigen and 23% were positive with swine HEV antigen. In contrast, 18% of the blood donors from the same eight U.S. states were positive with Sar-55 antigen and 17% were positive with swine HEV antigen. Swine veterinarians in the eight states were 1.51 times more likely when tested with swine HEV antigen (95% confidence interval, 1.03 to 2.20) and 1.46 times more likely when tested with Sar-55 antigen (95% confidence interval, 0.99 to 2.17) to be anti-HEV positive than normal blood donors. We did not find a difference in anti-HEV prevalence between veterinarians who reported having had a needle stick or cut and those who had not or between those who spent more time (> or = 80% of the time) and those who spent less time (< or = 20% of the time) working with pigs. Similarly, we did not find a difference in anti-HEV prevalence according to four job categories (academic, practicing, student, and industry veterinarians). There was a difference in anti-HEV prevalence in both swine veterinarians and blood donors among the eight selected states, with subjects from Minnesota six times more likely to be anti-HEV positive than those from Alabama. Age was not a factor in the observed differences from state to state. Anti-HEV prevalence in swine veterinarians and normal blood donors was age specific and paralleled increasing age. The results suggest that swine veterinarians may be at somewhat higher risk of HEV infection than are normal blood donors.     

Prevalence of specific antibody to hepatitis E virus in the general population of the community of Madrid, Spain

Hepatitis E virus (HEV) is an infectious agent causing hepatitis among humans. Although hepatitis E has been reported from many European countries, its incidence in Europe is largely unknown, and the prevalence of the HEV infection is also unknown for most countries of the region. Antibody to HEV (anti-HEV) was tested on 2,305 serum samples from the general population of the Community of Madrid (Spain) collected in the year 2008 among people aged 2-60 years. Total anti-HEV was tested by enzyme-immunoassay (EIA), and reactive samples were retested separately for anti-HEV IgG and IgM by recombinant immunoblot test (RIBT). Fifty samples (2.17%) displayed reactivity for total anti-HEV after EIA testing, and anti-HEV IgG was confirmed by RIBT in 25 (1.08%). The frequency of RIBT-confirmed anti-HEV ranged from 0.97% among the youngest to 3.61% among the oldest, and displayed a statistically significant trend to increasing with age. The rate of RIBT confirmation was also significantly higher among the individuals aged above 20 years old than among those younger of 21 years. HEV infection would be less frequent in the Community of Madrid than in Catalonia or the United Kingdom, and contact with HEV would be very uncommon among children and adolescents of the region. Confirmation of EIA-reactive samples by RIBT reduced the final numbers of anti-HEV testing as much as 50%, and some findings of this study suggest that such testing protocol would reflect better the real prevalence of anti-HEV in settings of low endemicity than the single testing by EIA.