珠海市部分注册猪场日本脑炎调查研究

〔目的〕了解珠海市部分注册养猪场猪群和从业人员的日本脑炎病毒血清抗体水平,预测人群日本脑炎的流行趋势。〔方法〕采用酶联免疫吸附法(ELISA),猪群检测血清IgG抗体,人群检测血清IgM抗体。〔结果〕2005年从珠海市的4个注册养猪场采集了1318份猪血清进行了日本脑炎病毒血清IgG抗体检测,结果抗体阳性率为37.1%;不同年龄段的猪群阳性率不同,分别为幼猪39.4%;中猪46.3%;成猪39.5%以及大猪30.3%。幼猪、中猪、成大、猪在不同月份血清抗体阳性率各不相同,幼猪群7月份阳性率稍高(52.3%),6月份次之(46.3%);中、成、大猪均为6月份阳性率高,分别为74.7%和43.5%。4个养猪场132名从业人员未能检出日本脑炎IgM抗体。〔结论〕研究结果表明养猪场猪群存在着日本脑炎病毒的隐性感染或曾经感染过,但感染率不高。应采取积极的预防措施,防止人群和猪场日本脑炎的发生与流行。     

戊型肝炎病毒基因型的研究进展

戊型肝炎病毒 (ＨＥＶ)是一种经胃肠道传播的致病因子 ,以前认为本病主要发生在亚洲、非洲和北美洲的发展中国家。最近血清流行病学调查发现 ,1%～ 2 %的美国及西欧献血员抗-ＨＥＶＩｇＧ阳性〔1,2〕,提示戊型肝炎 (ＨＥ)可能呈全球性分布。在灵长类、啮齿类及猪体内也检测到抗 -ＨＥＶ ,提示ＨＥ可能是一种动物源性疾病〔3～ 6〕。 1989年Ｒｅｙｅｓ等〔7〕首先应用分子克隆技术获得该病毒的基因克隆 ,并正式将此型肝炎及其相关病毒分别命名为戊型肝炎 (ｈｅｐａｔｉｔｉｓＥ)和戊型肝炎病毒 (ｈｅｐ ａｔｉｔｉｓＥｖｉｒｕｓ,ＨＥＶ)。尽…     

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。     

新疆2县猪、羊抗-HEV抗体流行状况调查

戊型肝炎病毒 (HepatitiusEVirus,HEV ) ,既往称为肠道传播的非甲非乙型肝炎病毒〔1〕。我国新疆曾发生大规模的戊型肝炎水型暴发流行 ,约有 11万余患者感染〔2〕,但水源被污染的原因尚不清楚。近年来 ,Meng等〔3〕 发现美国本土猪感染HEV ,提示HEV可经染毒的牲畜粪便污染水源。为探讨HEV造成水源污染原因 ,我们对新疆焉耆县和且末县猪、羊血清抗 -HEV抗体流行状况进行了调查。1　材料和方法1 1　样品来源　以随机抽样方法从新疆且末县和焉耆县屠宰场分别收集猪血 75份和 10 8份 ;羊血 119份和 170份 ;每份均 10ml,离心后取血清 -2 …     

常州市天宁区公共卫生从业人员HAV和HEV的感染状况及防治策略

目的了解本辖区从业人员中甲型肝炎病毒(HAV)和戊型肝炎病毒(HEV)的感染情况,以便更有效地防止甲型肝炎病毒和戊型肝炎病毒的传播。方法 2011年-2013年对辖区内84 990名从业人员进行抗甲型肝炎病毒Ig M抗体和抗戊型肝炎病毒Ig M抗体检测,同时对Ig M抗体阳性标本进行抗甲型肝炎病毒Ig G抗体和抗戊型肝炎病毒Ig G抗体检测,并对想继续从事服务行业的阳性人员进行Ig M抗体复检,同时皆做Ig G抗体检测,直到Ig M抗体不能检出时发放健康证明。结果 2011年-2013年从业人员中HAV感染率为0.061%,HEV感染率为0.16%,两者差异有统计学意义(P0.05);抗甲型肝炎病毒Ig M抗体阳性转阴复检次数最多为5次,抗戊型肝炎病毒Ig M抗体阳性转阴复检次数最多为6次。结论 HEV感染率明显高于HAV感染率。加强对甲型肝炎病毒和戊型肝炎病毒Ig M抗体阳性从业人员的管理,提高从业人员的卫生意识,严格控制甲型肝炎病毒和戊型肝炎病毒的传播途径。     

杭州地区妊娠晚期孕妇病毒性肝炎感染的调查研究

目的:调查杭州市2958例妊娠晚期孕妇乙型肝炎病毒(HBV)、丙型肝炎病毒(HCV)、丁型肝炎病毒(HDV)、戊型肝炎病毒(HEV)的感染状况。方法:对杭州市2958例妊娠晚期孕妇的血清乙型肝炎标志物、HCV抗体、HDV抗体、HEV抗体的检测结果进行统计分析。结果:2958例妊娠晚期孕妇中乙型肝炎总感染率40.16%,HCV抗体阳性率0.40%,HDV抗体阳性率0.20%,HEV抗体阳性率2.60%。结论:杭州地区妊娠晚期孕妇病毒性肝炎的感染以乙型肝炎位居第一、戊型肝炎次之,丙型肝炎及丁型肝炎感染率较低。应加强育龄女性易感人群乙肝疫苗的预防接种,开展和实施有效的预防措施来防止病毒性肝炎的感染,提高新生人口的素质。     

泰安市三种献血员人群庚型肝炎病毒检测分析

为了解献血员中HGV感染状况并探讨感染的危险因素。采用ELISA和RT -PCR技术 ,对泰安市 189名无偿献血员 ,40 4名职业献血员和 169名单采浆献血员进行了庚型肝炎病毒抗体检测和抗体阳性者进行病毒核酸的测定。三种献血员人群抗HGV阳性率为 1.5 9(3 /189)、0 .99% (4 /4 0 4)、5 .3 3 (9/169)、16例阳性者中HGVRNA阳性率分别为 (0 /3 )、2 5 % (1/4 )、44 .44 % (4 /9)。我市献血员人群中有庚型肝炎感染者 ,曾经献血浆的职业献血员和单采浆献血员仍是HGV筛检的重点人群。     

湖北省安陆市猪戊型肝炎血清流行病学研究

目的鉴于湖北省安陆市是猪养殖较为密集区,了解安陆市猪戊型肝炎的感染情况,对湖北省及其周边地区戊型肝炎的防控具有重要的公共卫生学意义。方法 2015年11月-2016年3月,从湖北省安陆市15个乡镇(开发区)共采集174份猪血清样品,其中22个规模猪场,122份血清,25个散养户,52份血清。样品中3月龄以下79份,3月龄以上95份。采用酶联免疫方法对戊型肝炎病毒抗体(HEV-Ab)进行检测。结果 174份猪血清HEV-Ab阳性率为37.9%。规模养殖(38.5%)与散养猪(36.5%)HEV-Ab阳性率差异无统计学意义(χ2=0.061,P=0.805)。阳性规模场占63.6%,阳性散养占40.0%,差异无统计学意义(χ2=2.616,P=0.106)。3月龄以下和3月龄以上猪的HEV-Ab阳性率分别为31.6%和43.2%,两者差异无统计学意义(χ2=2.428,P=0.119)。不同乡镇(开发区)猪HEV-Ab阳性率为0%~90%,差异有统计学意义(χ2=64.779,P=0.000)。结论本地猪群中存在较普遍的HEV感染情况,不同规模、场别、月龄不存在显著差异,不同乡镇(开发区)存在差异。     

兰州市猪戊型肝炎血清学及病毒基因型分析

目的 调查甘肃省兰州市猪戊型肝炎病毒(HEV)感染情况以及基因型.方法 收集兰州市部分地区猪血清,用ELISA诊断试剂盒分别检测HEV抗原和抗体;其中抗原阳性的血清,采用HEV ORF2引物进行套式逆转录聚合酶联反应(RT-PCR)扩增,对阳性扩增产物进行克隆和测序,并对序列进行分析,确定其基因型.结果 3月以下猪戊型肝炎病毒抗原、抗体阳性率分别为1.56%和90.27%,3个月以上分别为2.35%和86.99%,抗原、抗体水平在3月龄以上和以下二者中差异无统计学意义,抗原阳性血清共有22份,其中7份为HEV核酸阳性,其核苷酸序列与HEV 4型的同源性为82.2%～99.3%,分别为4a,4d和4f亚型.结论 兰州市猪群存在HEV感染,且为基因4型.     

云南省从业人员病毒性肝炎感染及防病知识调查

目的了解从业人员病毒性肝炎的感染状况及防病知识。方法随机选取参加健康体检的从业人员进行问卷调查并检测甲、乙、丙、丁、戊五型病毒性肝炎血清抗体。结果调查739名从业人员,大多为青壮年,流动性大,接触面广,但防病知识欠缺,知晓率低。13.5%的人员血清抗体检测到两种及多种肝炎阳性,15.0%的人五型肝炎血清抗体检测全阴;HAV-IgG阳性率为80.5%,1.76%的调查对象乙肝表面抗原阳性,丙肝感染率为0.94%,丁肝感染率为0.13%,15%的人近期感染过戊肝。25.0%的调查对象接种过乙肝疫苗3针,24.5%的人接种过甲肝疫苗。结论从业人员是病毒性肝炎流行环节中的重点人群,是亟待保护的群体;应加强对该群体的健康教育,提高他们维护健康、预防疾病、自我保护的能力。     

Detection of IgM and IgG against hepatitis E virus in serum and meat juice samples from pigs at slaughter in Bavaria, Germany

Hepatitis E virus (HEV) is an emerging foodborne pathogen with domestic and wild pigs (and likely other species such as deer or rabbits) recognized as reservoir. Pathogenesis in pigs usually leads to an asymptomatic course of disease. Since there is no enzyme-linked immunosorbent assay (ELISA) kit for the detection of anti-HEV antibodies in pigs commercially available, the objective of this study was to assess the seroprevalence in fattening pigs at slaughter and at herd level using a newly developed ELISA based on genotype (GT) 1 and GT 3 in Bavaria, Germany. Based on 516 serum and 198 meat juice samples collected from different herds at four different Bavarian slaughterhouses, the overall seroprevalence of anti-HEV IgG in serum and meat juice samples was 68.6% and 67.6%, respectively. Analyzing the serum for the presence of anti-HEV IgM, 36/516 (7%) were positive for anti-HEV IgM. At herd level, most of the herds were seropositive for anti-HEV antibodies. The present study shows that HEV is widespread among the Bavarian pig population and that some pigs might test positive for anti-HEV IgM even at the age of slaughter. Also, meat juice serves as an equivalent matrix to serum to test for anti-HEV antibodies in pigs.     

福建省戊型肝炎病毒感染的血清流行病学调查

目的了解福建省动物种群及人群中戊型肝炎病毒(HEV)的感染情况。方法收集猪、犬、乳牛、山羊和啮齿动物(黄胸鼠及褐家鼠)等5种与人类关系密切的哺乳动物血清标本共1151份,收集普通人群血清标本2209份,暴露人群血清标本1722份,应用ELISA检测抗-HEV IgG抗体。结果不同动物HEV感染率有差异(x2=406.25,P<0.01),其中猪的感染率为71.31%,散养家猪(70.00%-94.12%)HEV感染率高于大型专业养猪场(39.77%),不同生长期(≥4月龄)的猪其HEV感染率未见不同。普通人群HEV的阳性率为23.3%,暴露人群HEV阳性率为33.3%;暴露人群阳性率显著高于普通人群。在暴露人群中与鸡密切接触者,HEV的阳性率显著高于与猪密切接触者。HEV阳性率有随年龄的增长而上升的趋势,在普通人群中,男、女性HEV阳性率差异无统计学意义(P>0.05);但在暴露人群中男性HEV阳性率显著高于女性。结论猪和暴露人群HEV的感染率较高;与猪、鸡密切接触者HEV阳性率高于普通人群,证明了HEV可能是一种人兽共患病。     

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.     

Seroprevalence and distribution of hepatitis E virus in various ethnic groups in Gansu province,China

Gansu province is located in northwestern China and is home to 45 ethnic groups including Han, Hui, Zang and others. Different ethnic groups have varying involvement with livestock and meat consumption, especially pork. To investigate the prevalence of hepatitis E virus (HEV) infection and the distribution of HEV genotypes among the major ethnic groups in Gansu province, 2090 serum samples were collected from individuals from four regions and three ethnic groups, the Han, Hui and Zang. All serum samples were tested for anti-HEV IgG and IgM antibodies, as well as HEV antigen, and selected samples were then tested for HEV RNA. The data showed that the seroprevalence of anti-HEV IgG in the Hui, Han and Zang ethnic groups from the four regions was 8.9%, 18.7% and 32.9%, respectively, and these differed significantly (P < 0.05). The seroprevalence of anti-HEV antibody for each ethnic group varied among the different regions. In general, within the same region, the three ethnic groups also show differences. Genomic analysis indicated that HEV isolated from humans belonged to genotype 4, and resembled closely swine HEV isolates from Gansu province. The seroprevalence of anti-HEV antibodies was in accordance with the amount of contact with pigs in the different regions. Pigs are the primary host for HEV, so people in frequent contact with pigs may be at risk of zoonotic infection. However, populations that have rare contact with pigs are more likely to be susceptible to HEV when exposed, suggesting that should be the target of vaccination.     

戊型肝炎病毒IgG抗体诊断试剂盒的研制及初步应用

目的 应用大肠杆菌表达的戊型肝炎病毒(HEV)重组抗原建立HEV IgG抗体诊断(ELISA)试剂盒.方法 应用大肠杆菌表达的具有戊型肝炎主要抗原表位的表达蛋白HEV ORF23作为包被抗原,建立检测血清中抗HEV IgG的间接ELISA试剂盒.通过HEV IgG试剂盒对100份戊型肝炎患者血清和150份正常人阴性血清测定结果进行比较,评价本试剂盒的特异性、敏感性及稳定性.另选临床500份肝炎患者血清进行检测,评价本试剂盒的临床应用价值.结果 建立的抗HEV IgG间接ELISA试剂盒特异性、敏感性均为100%,重复性较好,在4℃至少可稳定存放6个月,与同类试剂的符合率为95%以上.500份血清样本中,戊型肝炎患者150例,检出HEV145份,阳性符合率为96.67%.结论 应用大肠杆菌表达的HEV重组抗原建立的检测试剂盒对血清抗HEV IgG的检测具有良好的特异性和敏感性,在戊型肝炎的临床诊断和流行病学调查中具有潜在的应用价值.     

Comparison of hepatitis E virus genotypes from rabbits and pigs in the same geographic area: No evidence of natural cross-species transmission between the two animals

Domesticated pigs have been shown to be a reservoir of genotypes 3 and 4 hepatitis E virus (HEV). Farmed rabbits were recently recognized as the host of a novel virus, rabbit HEV. In order to determine whether HEV is transmitted naturally between rabbits and pigs, a survey on HEV infections was conducted in rabbits and pigs aged 2–4 months from rabbit and pig farms located near to each other in nine villages in three counties of Hebei Province, China. The overall anti-HEV antibody positivity rates in serum samples of swine and rabbits were 61.7% (58/94) and 23.2% (67/289), and the positive rates for HEV RNA were 23.4% (22/94) and 10% (29/289), respectively. In addition, 37 of 125 swine fecal samples (29.6%) were HEV RNA positive. The nucleotide sequences of a 304 bp region within HEV ORF2 have identity ranging from 84.5% to 100% among the rabbit isolates and from 82.3% to 100% among the swine isolates. In contrast, the nucleotide identity between the two species groups was only 72–76.6%. Consequently, the two groups were clearly separated in the phylogenetic tree that showed all of the rabbit isolates are closely related to the rabbit HEV reported recently and the swine isolates belong to genotype 4, including subgenotypes 4a, 4c and 4d. The results showed that HEV is highly prevalent in farmed rabbits and pigs in these areas. However, genotype 4 HEV and rabbit HEV are circulating separately in pigs and rabbits in the same area. In conclusion, there was no evidence of cross-species transmission of HEV between pigs and rabbits. The frequency of HEV transmission events between these two animal species is likely low in commercial farms.     

Seroepidemiology and genetic characterization of hepatitis E virus in the northeast of china

The aim of this study was to analyze the prevalence of infection and genotype of hepatitis E virus (HEV) in people and animals in the northeast of China (Heilongjiang, Jilin and Liaoning provinces). This seroepidemiological study was conducted using enzyme immunoassays and human sera positive for HEV antigen or anti-HEV IgM, and animal sera positive for HEV antigen or with an S/CO ≤10 for anti-HEV were tested for HEV RNA using real-time RT-PCR and nested RT-PCR. In humans, the overall prevalence of anti-HEV IgG was 31.6% (311/985), 28.6% (147/514) and 21.1% (841/3994) in individuals frequent, infrequent, and very rare contact with swine, respectively. The overall prevalence of anti-HEV was 81.6% (1737/2127) in pigs above 3 months of age, 66.4% (1644/2473) in pigs below 3 months of age, 18.7% (301/1612) in cattle and 12.4% (162/1302) in sheep. 1211 samples were tested for HEV RNA using real-time RT-PCR and 71 were positive. 30 of the 71 samples also were positive for HEV RNA using nested RT-PCR. These 30 isolates shared 81.2–100% sequence identity with each other at the nucleotide level and belonged to HEV genotype 4, regardless whether from human or animals. The results indicate that HEV infection is widely spread in the northeast of China. The prevalence of anti-HEV in individuals with frequent contact with pigs was significantly higher than those without and the HEV sequences isolated from such individuals were related more closely to isolates from pigs. These support strongly the hypothesis of a zoonotic origin of hepatitis E.