套式逆转录PCR检测戊型肝炎病毒RNA的临床应用

目的 评价套式逆转录PCR检测血清戊肝病毒(HEV) RNA的临床意义.方法 对GenBank数据库中的戊型肝炎病毒全基因组序列进行分析比对,并针对国内流行的HEV株序列,选择位于ORF2的保守区域设计引物,建立套式逆转录聚合酶链式反应(nRT-PCR)方法,并检测126例急性戊型肝炎患者,并与检测抗-HEV IgM的方法进行比较.结果 126例急性戊型肝炎患者血清中有67例HEV-RNA阳性,对照组血清HEV-RNA检测均为阴性;与血清抗HEV IgM检测结果比较,HEV RNA检测的总符合率为80.91％,两种方法的检测结果具有良好的一致性;nRT-PCR方法检测HEV-RNA与血清抗-HEV IgM检测方法存在明显的差异,不能相互替代,而有一定的互补性;3例患者的首份血清检测为HEV-RNA阳性,但抗-HEV IgM为阴性,系列追踪检测,均相继出现抗HEV IgM,急性戊型肝炎患者血清HEV-RNA的检出多在发病的1～12 d.结论 应用nRT-PCR方法能对急性散发戊型肝炎患者血清中的HEV RNA进行定性检测,且有较高的特异性和敏感性,临床使用可以提高对HEV早期诊断的水平,具有一定的临床应用价值.     

广西地区猪、鼠、狗戊型肝炎病毒感染血清学分析

目的了解广西地区猪、鼠和狗血清中抗．戊型肝炎病毒（HEV）IgG抗体流行情况。方法应用HEV基因1型开放读码框（ORF）2和ORF3多肽包被酶标板，辣根过氧化物酶（HRP）标记的羊抗猪、羊抗鼠和羊抗狗建立的酶联免疫吸附试验（ELISA）法检测猪、鼠和狗血清中抗．HEV IgG。结果总抗．HEV IgG阳性率为31．84％（170／534），其中猪血清抗．HEV IgG阳性率为26．40％（66／250），鼠血清抗．HEV IgG阳性率为43．02％（77／179），狗血清抗．HEV IgG阳性率为25．71％（27／105）。结论猪、鼠和狗血清中存在HEV感染，鼠抗．HEV IgG阳性率最高。     

北京市郊区八种动物戊型肝炎病毒抗体流行率调查及病毒基因型研究

目的 调查北京地区与人密切接触的猪、牛、羊、马、驴、犬、鸡、鸭8种动物血清中戊型肝炎病毒(HEV)抗体流行率及该地区猪HEV基因型和亚型.方法 收集8种动物的血清标本及幼猪粪便标本,用双抗原夹心ELISA法检测血清中抗-HEV;用巢式反转录聚合酶链反应法(RT-nPCR)检测HEV RNA;对部分PCR产物进行克隆和测序,并对测序结果进行基因分型.结果 在8种动物中抗-HEV阳性率分别为猪80.43%(481/598),其中成猪(>6月龄)为87.86%(369/420),幼猪(2～3月龄)为62.92%(112/178);牛15.02%(52/346);马14.29%(40/280);驴0(0/26);羊9.88%(33/334);犬0(0/21);鸭3.03%(7/231);鸡2.53%(8/316).RT-nPCR检测3月龄以下猪粪便标本HEVRNA阳性率为66.67%(74/111).HEV RNA阳性的标本测序后可归为6株(分别命名为bjsw1、bjsw2、bjsw3、bjsw4、bjsw5和bjsw6),6株HEV开放读码框2(ORF2)部分核苷酸序列的相似性为94.5%～99.6%,与1、2、3、4型HEV的相似性分别为75.6%～78.6%、75.6%～76.2%、77.1%～80.7%和83.7%～94.5%.6株HEV与人HEV 4d亚型的同源性最高,为90.0%～94.5%.结论 北京市郊区猪、牛、马、羊、鸭、鸡中均存在HEV感染,其中猪抗-HEV流行率最高,驴、犬抗-HEV的流行率最低;6株猪HEV属于基因4型、4d亚型.     

戊肝病毒(HEV)在猪和牛群中的流行病学研究

目的 探讨戊型肝炎病毒（HEV）在猪和牛群中的感染情况。方法 用抗－HEV抗体试剂盒检测猪和牛血清中的抗体；对部分血清用逆转录聚合酶链的方法（RT－PCR）检测HEV RNA，并对PCR阳性产物进行克隆，然后将序列进行分析。结果 281份猪血清中有235份为抗－HEV抗体阳性，阳性率为83.6%；其中56份血清中有3份为HEV RNA阳性，序列分析显示从猪中克隆的3株序列（SB2、SH1和SJ14）之间在ORF2（6007－6354bp）区域的核甙酸序列的同源性为83％－86％，该3株序列在ORF2区与1，2，3，4型的同源性分别为74％－79％、73％－77％，73％－76％和83％－93％；190份牛血清中有12份为抗－HEV抗体阳性，阳性率为6.3%。结论 HEV在猪和牛群中均有流行，但在猪群中的流行率明显高于牛群，猪感染的HEV的基因序列与人群中散发性戊型肝炎病毒的4型同源性最高。     

华东和华南地区商品猪戊型肝炎病毒携带率和基因分型分析

目的 了解华东和华南地区商品猪戊型肝炎病毒(HEV)的携带率和基因分型.方法 2007-2009年收集华东和华南地区5家屠宰场商品猪胆汁600份,应用巢式RT-PCR方法检测HEVRNA,测序后做系统进化分析.结果 600份猪胆汁中有47份(7.83%)分离出HEVRNA.基于HEV ORF2区域内150-nt序列的系统进化分析结果,分离的47份HEV病毒株均属于Ⅳ型,与Ⅰ、Ⅱ、Ⅲ和Ⅳ型参考病毒株的核苷酸同源性分别为75.0%～83.4%、75.0%～84.6%、71.9%～80.7%和88.1%～91.5%,且大部分病毒株按采样地区来源表现出地区聚集性.结论 HEV在华东和华南地区的商品猪中广泛存在,应加强对商品猪食用安全问题的关注.     

湖北地区出口猪及不同人群中戊型肝炎病毒感染调查研究

〔目的〕调查湖北地区出口猪以及不同人群中戊型肝炎病毒的流行情况,为制定预防措施提供依据。〔方法〕从湖北地区8个出口猪场中共采集3个月龄以下猪的血清203份,3个月以上猪的血清637份。从不同人群(包括猪场和屠宰厂从业人员、农村居民以及献血员中共采集1585份血清样品。用酶联免疫方法分别检测戊型肝炎病毒抗体以及抗原,对部分样品采用实时荧光聚合酶链反应检测戊型肝炎病毒核酸。〔结果〕3个月龄以下和3个月龄以上猪血清中戊型肝炎病毒抗体的阳性率分别为56.65%和87.13%,2者间差异具有显著性(t=7.79,p<0.01);戊型肝炎病毒抗原的阳性率分别为9.35%和10.36%,2者间差异无显著性。在328份猪血清中,抗原和核酸的符合率为78.80%。猪场和屠宰厂从业人员、农村居民以及献血员中戊型肝炎病毒IgG抗体的阳性率分别为55.72%(263/472)、31.63%(99/313)、27.00%(81/300)和33.40%(167/500)。猪场从业人员戊型肝炎病毒IgG抗体阳性率与其他3类人群的相比,具有非常显著性差异(t=8.88,p<0.01)。〔结论〕猪群中戊型肝炎感染率较高,与猪密切接触人群的感染率高于其他人群。因此,应加强出口猪场的管理,减少戊型肝炎病毒在人畜之间的传播。     

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.     

某农村人群甲、乙、丙、戊和庚型肝炎病毒感染的现况研究

目的　了解某农村人群甲、乙、丙、戊和庚型肝炎病毒的感染状况及其流行特点。方法　应用酶联免疫试验 (EIA)检测血清抗 -HAV、HBsAg、抗 -HBs、抗 -HBc、抗 -HCV、抗 -HEV和抗 -HGV ,并对抗 -HGV阳性者应用套式逆转录聚合酶链反应法 (RT -nPCR)检测HGVRNA。结果　该人群抗 -HAV、抗 -HCV、抗 -HEV和抗 -HGV流行率分别为 86.9%、11.5 %、2 .9%和 1.8% ,HBsAg阳性率为8.0 % ,HBV总感染率为 5 4.8%。HAV以 5岁以下儿童感染率最低 ( 35 .0 % ) ,到 10岁时 85 .0 %的儿童已感染HAV。HBsAg阳性率呈现两个高峰 ,分别在 5～ 9岁和 40～ 49岁年龄组 ;HBV总感染率到 10岁时为 5 5 .0 % ,然后随年龄增长而上升。HCV感染主要集中在 2 0～ 49岁年龄组 (占 77.8% )。各型肝炎病毒男女感染率无明显差异。献浆次数、年限与HCV、HEV、HGV感染呈正相关。HBsAg、抗 -HBc、抗 -HCV呈现家庭聚集性 ,但仅HBsAg呈现母亲与子女相关。抗 -HCV阳性者中ALT异常率 ( 15 .9% )显著高于抗 -HCV阴性者 ( 1.2 % ,P <0 .0 1)。结论　该人群甲、乙、丙、戊和庚型肝炎病毒感染具有不同的流行病学特点 ;献血浆是该人群HCV、HEV和HGV感染的主要危险因素 ;抗 -HCV阳性者多伴有肝损害     

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.     

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。     

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.     

两种戊型肝炎IgM抗体诊断试剂的比较

目的 比较两种戊型肝炎病毒(HEV)IgM抗体诊断试剂的可靠性.方法 用北京万泰抗HEV-IgM抗体(万泰-IgM)和新加坡MP抗HEV-IgM抗体(MP-IgM)诊断试剂、北京万泰抗HEV-IgG抗体诊断试剂检测92例健康体检者、71例可疑戊型肝炎患者、55例确诊急性戊型肝炎患者、50例类风湿因子(RF)阳性患者、54例抗甲型肝炎病毒(HAV)-IgM阳性者的相应HEV抗体.逆转录聚合酶链反应法(RT-PCR)检测部分可疑戊型肝炎患者的HEV RNA.结果 检测可疑戊型肝炎患者、急性戊型肝炎患者及健康体检者时万泰-IgM、MP-IgM符合率为73.39%(160/218),阳性率差异无统计学意义[46.79%(102/218)比44.04%(96/218),χ2=0.62,P＞0.05].在检测可疑戊型肝炎患者时,万泰-IgM诊断HEV急性感染的敏感性(83.08%,54/65)比MP-IgM(78.46%,51/65)高,但差异没有统计学意义(χ2=0.16,P＞0.05).HEV RNA阳性(35例)的可疑戊型肝炎患者中,万泰-IgM检测敏感度(97.14%,34/35)也明显比MP-IgM(74.29%,26/35)高,差异有统计学意义(χ2=4.9,P＜0.05).55例确诊的急性戊型肝炎患者中,万泰-IgM的敏感度(87.27%,48/55)显著高于MP-IgM(67.27%,37/55),差异有统计学意义(χ2=4.0,P＜0.05).万泰-IgM诊断HEV急性感染的特异度(100.00%,202/202)比MP-IgM(89.11%,180/202)好,差异有统计学意义(χ2=20.05,P＜0.005).RF、抗HAV-IgM阳性时会引起MP-IgM假阳性,但不干扰万泰-IgM结果.结论 万泰-IgM试剂是良好的急性戊型肝炎诊断试剂.     

中国南方某农村地区人与猪戊型肝炎病毒的检测和部分序列分析

目的调查中国南方某农村地区戊型肝炎病毒（HEV）人株与猪株的相关性。方法应用逆转录-巢式聚合酶链法（RT—nPCR）对一般人群中HEV-IgM阳性者、急性戊型肝炎患者和当地某养猪场的猪进行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132份猪粪便标本中13份为HEV RNA阳性；26份IgM阳性一般人群血清标本中有4份HEV RNA阳性；4例急性戊型肝炎患者中有1例的血清和粪便标本为阳性。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89．3％～100．0％，这10株HEV序列与HEVⅠ型、Ⅱ型、Ⅲ型和Ⅳ型在同一区域的核苷酸序列的同源性分别为78．7％～84．7％、83．3％～85．3％、76．0％～80．0％和84．7％～95．3％。结论该地区人群及猪群中流行的HEV同属基因Ⅳ型。     

Hepatitis E virus in domestic pigs and surface waters in Slovenia: Prevalence and molecular characterization of a novel genotype 3 lineage

A novel hepatitis E virus (HEV) genotype 3 lineage was identified in Slovenian pig herds. Stool samples from six Slovenian pig farms were collected and tested for the presence of HEV RNA. Of 85 individual samples 15 (20.3%) were positive for HEV RNA of which 2/38 (5.3%), 6/21 (28.6%) and 7/26 (26.9%) were from suckling, weanling and fattening pigs, respectively. Additionally, 51 pooled porcine stool samples were tested in one of the biggest pig farm and the estimated infection rate of individual pig was calculated, resulting in 7.8%, 10.6% and 24.2% for suckling, weanling and fattening pigs, respectively. The majority of HEV positive porcine samples were from the same pig farm. Out of 17 Slovenian patients with confirmed recent hepatitis E in the period 1999–2011, the serum samples of 10 patients were tested and 3 samples turned out to be HEV RNA positive. Furthermore, 60 surface water samples were tested throughout the country, of which 2 (3.3%) were positive for HEV RNA, one of them in the near vicinity of a pig farm. All HEV strains were analysed at 5’ ORF1 and 5’ ORF2 regions and both genome regions confirmed that Slovenian HEV strains represent a distinct genotype 3 lineage, diverse from all other genotype 3 lineages available in GenBank and described in the literature to date. All but one HEV strains detected in pigs in Slovenia represent a monophyletic branch in phylogenetic trees, with a high degree of sequence identity. One human HEV strain belonged to genotype 1 and two to genotype 3 but did not match the new genotype 3 lineage detected in Slovenian pig herds.     

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.     

华东地区散发性戊型肝炎病毒系统进化分析

目的 了解华东地区散发性戊型肝炎病毒(HEV)的系统进化特征.方法 2005-2008年收集华东地区14家二级或三级医院413份散发戊型肝炎患者血清,应用巢式RT-PCR方法检测HEVRNA并测序.参照GenBank相关序列,分析各序列之间的同源性,并构建进化树.结果 413例患者的男女性别比为1.75:1,40～69岁患者居多(61.5%).413份患者血清有140份分离出HEV RNA,阳性分离率为34%.所有分离的140份病毒株均属于HEV Ⅳ型,与Ⅰ、Ⅱ、Ⅲ和Ⅳ型参考病毒株的核苷酸同源性分别为77.9%～88.3%、80.8%～90.6%、73.4%～85.2%和91.0%～95.4%.结论 基因Ⅳ型HEV是引起华东地区散发性戊型肝炎的优势病毒株,其起源和进化等问题仍需进一步研究.     

HAV and HEV infection in hospitalised hepatitis patients in Alexandria, Egypt

A total of 202 serum and stool samples from acute hepatitis patients attending the Fever Hospital of Alexandria, Egypt, have been studied to reveal markers of hepatitis virus infection. Anti-HAV IgM were detected in 21 out of 202 sera (10.4%), whereas 201 sera (99.5%) had anti-HAV IgG. The first age attack was in the class-age 0–9 years with 64.7% of anti-HAV IgM positive sera. Among 202 patients, anti-hepatitis E IgG (sample/over cut off>1.0) was identified in 90 patients (44.5%). The anti-HEV seropositivity ranged from 17.6% to 60.0% in the different age groups, with the highest level in the class-age 20–29 years. Anti-hepatitis E IgM were identified in 49 patients with the first age attack in the class-age 10–19 years (39.4%). HAV RNA was identified by nested PCR in 7 samples out of 15, whereas HEV RNA was present in 4 out of 75 stool samples. Direct DNA sequence of the latter PCR products confirmed the presence of the HEV genome; comparison of the sequences of the isolates from Egypt with those in data banks revealed the highest homology to the Burma strain. Our data confirm that HAV and HEV are common causes of acute sporadic hepatitis in Alexandria but with different peak age positivity. Occasionally, but not infrequently, dual infections (HAV–HEV and HEV-enteric viruses) were also found. The risk analysis indicates that patients living in rural areas are exposed to a higher risk of hepatitis E infection compared to the urban population, whereas the presence of anti-HEV IgG was significantly associated with consumption of common village water and use of indoor dry pit and oral therapy for schistosomiasis.     

山东省某地屠宰场猪肝内戊型肝炎病毒感染状况研究

目的研究商品猪肝脏内戊型肝炎（戊肝）病毒（HEV）的检出状况及其基因分型。方法采集35份山东省某个人屠宰场和某城镇大型屠宰场内的猪肝，处理后采用逆转录．巢式聚合酶链反应（nested RT·PCR）方法检测HEV RNA。并与GenBank中登录的HEV全长序列进行同源性分析。结果35份猪肝标本中共有3份检出HEVRNA，阳性率为8．57％。同源性分析显示这3株病毒均为Ⅳ型HEV。结论即将上市的商品猪肝脏内存在HEV感染，其基因型与中国大陆HEV流行株相同，均为基因Ⅳ型。     

First documented outbreak of hepatitis E virus transmission in Java,Indonesia

A suspected hepatitis outbreak occurred in Bondowoso District, East Java Province, Indonesia, in March-May 1998. An investigation was initiated in April 1998, involving a retrospective review of hospital records, a community-based cross-sectional study, and a health service-based case detection and household follow-up. Sera and epidemiological information were collected from 962 individuals: 235 from 3 outbreak-affected communities along the same rural stretch of river, 101 from community controls living distant from the river, 151 cases detected in health centres, 141 family members of the cases, and 334 subjects from neighbouring families. The prevalence of acute hepatitis E virus (HEV), based on anti-HEV IgM, total antibody (Ig) to HEV and polymerase chain reaction (PCR), was significantly (P < 0.00001) higher (52.4%) among the outbreak communities than among the community controls (3%). The background prevalence of HEV, based on anti-HEV IgG, was also significantly (P < 0.00001) higher (47%) among the outbreak communities than among the community controls (3%). None of the 476 sera screened for anti-HAV (hepatitis A virus) IgM was positive. These results indicate that HEV was the aetiological agent responsible for the outbreak. The overall attack rate (AR) for the 3 outbreak-affected communities surveyed was 19%, with AR determined on the basis of clinically recognized, acute jaundice illness. The usage of river water as primary source for bathing, human-waste disposal, and drinking purposes differed significantly (P < 0.00001) between the communities in outbreak areas and those in non-outbreak areas. There is no significant influence attributed to 'boiling water' on acute HEV. No climatic influences (flooding or drought) predisposed this instance of epidemic HEV transmission. This outbreak represents the first documented evidence of epidemic HEV transmission in Java, Indonesia.