Seroepidemiology of hepatitis A and E virus infections in Tehran, Iran: a population based study

Hepatitis A virus (HAV) and hepatitis E virus (HEV) are enteric hepatotropic viruses and their prevalence is related to the sanitary conditions of the region under investigation. There are only a few studies on the seroepidemiology of these two viruses in the general Iranian population. The purpose of this investigation was to measure the prevalence of hepatitis A and E infections in the general population. Between 2006 and 2007, a cross sectional study was performed in Tehran, Iran. Blood specimens were collected and questionnaires were filled in for 551 persons. Patient sera were tested by ELISA for anti-HEV and anti-HAV IgGs. The χ(2) test and independent t-test were used for statistical analysis and p<0.05 was considered significant. The overall seroprevalence rates of anti-HEV IgG and anti-HAV IgG were 9.3% and 90%, respectively. The prevalence of antibodies to HAV and HEV was greater among men than women and increased with age. However, there was no significant relationship between age and gender with the existence of anti- HAV and HEV IgG antibodies. Our results show the seroprevalence of HAV and HEV antibodies are high and both viruses are endemic in this region. These findings are in accordance with results obtained from previous studies. We recommend that foreign travelers to Iran are vaccinated against HAV.     

Role of hepatitis E and other hepatotropic virus in aetiology of sporadic acute viral hepatitis: A hospital based study from urban Delhi

Major hepatotropic virus continues to be an important cause of acute viral hepatitis (AVH) in developing countries like India. While epidemics of AVH have been well studied few serious sporadic cases from developing countries have been reviewed. We studied prospectively 75 cases of sporadic AVH who reported to our hospital and were evaluated for the presence of various hepatotropic viruses. The seroprevalence of IgG anti-HEV antibodies was studied in the general population as a control. We found 53.3% (40/75) of sporadic AVH cases were due to hepatitis E virus while 11% (8/75) were due to hepatitis B virus. Hepatitis C virus was responsible for 8% (6/75) of the sporadic AVH cases and hepatitis A was found in 5% (4/75) of the cases. No causative agent was found in 23% (17/75) of the sporadic AVH cases. The sporadic AVH cases due to HEV were not clinically or biochemically not different from AVH due to other viruses. We found a high prevalence of IgG anti-HEV in 35.6% (178/500) among the general population of urban Delhi. The study suggested that hepatitis E was the most common cause of sporadic AVH in urban Delhi. High seroprevalence of IgG anti-HEV antibodies in the general population and amongst the sporadic AVH cases suggests that it is unlikely to be protective antibody. IgM anti-HEV positive serology is considered diagnostic of acute hepatitis E infection in India, where hepatitis E is endemic.     

Seroprevalence of hepatitis E virus infection, rural southern People's Republic of China

Genotype 4 hepatitis E virus (HEV) is the dominant cause of hepatitis E in the People's Republic of China; swine are the principal reservoir. Our study was conducted in 8 rural communities of southern China, where families keep pigs near their homes. Phylogenetic analysis showed that 23 of 24 concurrent virus isolates from this region are genotype 4 strains. Among the study populations, immunoglobulin G anti-HEV seroprevalence accumulated with age at approximately equal to 1% per year for persons < or =60 years of age. After age 30 years, seroprevalence increased at higher rates for male than for female study participants. The overall seroprevalence was 43% (range 25%-66%) among the communities. Infection rates were higher for participants between 25 and 29 years of age. The results suggest that HEV infection probably has been endemic in southern China for at least 60 years, with swine being the principal reservoir of human HEV infection in recent years.     

Prevalence of anti-HAV and anti-HEV antibodies in Konya, Turkey

OBJECTIVE: To determine the prevalence of antibodies to hepatitis A (HAV) and E (HEV) viruses in the different areas of Konya. METHODS: Anti-HAV and anti-HEV antibodies were investigated in 210 healthy children randomly selected (100 from rural areas and 110 from urban areas of Konya). None gave a history of previous icterus nor other signs of hepatitis, had received blood transfusion and HAV vaccine, or had been on hemodialysis. RESULTS: Evidence of HAV infection occurred in children under the age of 6 years. The seroprevalence rate was 67.8% in rural areas and 25.8% in urban areas. This increased rapidly with age and became universal after 11 years of age in both areas. In contrast, HEV infections were not detected until children were 6-11 year olds, and the 5.2% seroprevalence rate in urban areas and 8.5% seroprevalence rate in rural areas in this age group did not significantly increase in older age group. The prevalence of anti-HAV as well as anti-HEV was significantly higher in children with poor socio-economic conditions in both areas. CONCLUSIONS: These results suggest that HAV infection in rural areas of Konya is widespread and that environmental and socio-economic factors play a major role in its transmission. In contrast, hepatitis E is not a public health problem in Konya.     

Bayesian estimation of hepatitis E virus seroprevalence for populations with different exposure levels to swine in The Netherlands

Hepatitis E virus (HEV) is ubiquitous in pigs worldwide and may be zoonotic. Previous HEV seroprevalence estimates for groups of people working with swine were higher than for control groups. However, discordance among results of anti-HEV assays means that true seroprevalence estimates, i.e. seroprevalence due to previous exposure to HEV, depends on choice of seroassay. We tested blood samples from three subpopulations (49 swine veterinarians, 153 non-swine veterinarians and 644 randomly selected individuals from the general population) with one IgM and two IgG ELISAs, and subsets with IgG and/or IgM Western blots. A Bayesian stochastical model was used to combine results of all assays. The model accounted for imperfection of each assay by estimating sensitivity and specificity, and accounted for dependence between serological assays. As expected, discordance among assay results occurred. Applying the model yielded seroprevalence estimates of approximately 11% for swine veterinarians,approximately 6% for non-swine veterinarians and approximately 2% for the general population. By combining the results of five serological assays in a Bayesian stochastical model we confirmed that exposure to swine or their environment was associated with elevated HEV seroprevalence.     

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.     

Hepatitis E antibodies in Egyptian adolescent females: their prevalence and possible relevance

Hepatitis E virus has been implicated as a frequent cause of acute sporadic hepatitis among Egyptian children. Moreover, an extraordinarily high seroprevalence rate was previously reported in a semiurban Nile Delta population. A conspicuous feature of hepatitis E is the high morbidity and mortality it can cause among infected pregnant women. We therefore evaluated the prevalence of HEV antibodies in adolescent females using a solid-phase enzyme linked immunoassay based on two recombinant hepatitis E virus antigens. A high prevalence rate (38.9%) was found in 95 apparently healthy adolescent females. The mean age of the study subjects was 21.81 +/- 2.5 (SD) range 16-25 years. Eighty (84.2%) subjects resided in Alexandria, while 15 (15.8%) came from semiurban villages of Alexandria Governorate. An increased prevalence was noted with age, as anti-HEV antibodies were detected in 32.1% and 41.8% of study participants in the second and third decades of life, respectively. Similarly, those illiterate or having received less than primary education exhibited a higher HEV prevalence than those with higher education (46.3% vs 29.3%). The majority of subjects having serological evidence of HEV infection denied previous history of jaundice which shows that HEV infection was subclinical in those cases. Ten (55.6%) pregnant females participating in the study, as well as 48 (62.3%) non pregnant females lacked serological evidence of HEV infection; i.e., 60.01% (10 + 48 out of 95) of women in the childbearing age may be susceptible to infection. This report suggests that HEV is endemic in Alexandria, Egypt; the epidemiologic risk factors associated with HEV infection need further exploration.     

北京市戊型肝炎血清流行病学调查

目的了解北京市自然人群中抗-HEVIgG流行状况,为戊肝防控工作提供依据。方法在北京市10个区县按整群随机抽样方法调查1岁以上各年龄组自然人群并采集静脉血,采用科华公司ELISA试剂盒检测抗-HEVIgG。调查结果采用SPSS13.0进行分析。结果北京市自然人群中抗-HEVIgG阳性率为8.13%（95%CI：7.37%～8.89%）,标化阳性率为6.53%。不同性别间抗-HEVIgG阳性率差异无统计学意义;随年龄的增长阳性率呈不断增加的趋势;城区阳性率低于郊区,差异有统计学意义（χ2=4.556,P=0.033）。结论北京市自然人群中戊肝感染率较高,部分农村地区抗-HEVIgG阳性率较高。     

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.     

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.     

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.     

Hepatitis E virus infection in work horses in Egypt.

Hepatitis E virus (HEV) is an important cause of hepatitis among young Egyptian adults with high seroprevalence rates seen in both rural areas of the Nile Delta and in suburban Cairo. Because natural antibodies to HEV have been detected in animals and zoonotic transmission is postulated, we surveyed work horses in Cairo for evidence of HEV exposure and viremia. Sera from 200 Cairo work horses were tested by ELISA for the presence of IgG anti-HEV antibody revealed a seropositivity of 13%. Among 100 samples processed for detection of viral genome by means of nested polymerase chain reaction (N-PCR), 4% were positive and indicative of viremia. Viremic animals were less than 1 year old. Relative to PCR-negative horses, PCR-positive animals demonstrated significant elevation of AST (p=0.03). Phylogenetic analysis of a 253-bp fragment, in the ORF-1,2,3 overlap region of the HEV genome from the viremic animals showed that three of these viral strains to be identical, and closely related (97-100% nucleotide identity) to two human isolates from Egypt, and distant (78-96%) from 16 other HEV isolates from human and animals and shared 99.6% NI with the fourth strain. The consensus sequence of the four strains was origin obtained elsewhere. These data indicated that horses acquire HEV infection and suggest that cross-species transmission may occur. Whether horses play a role in the transmission of HEV needs further investigation.     

武汉市普通人群戊型肝炎血清学及影响因素分析

目的 评估武汉市普通人群戊型病毒性肝炎病毒（戊型肝炎病毒,hepatitis E virus,HEV）感染状况及影响因素。方法 采用多阶段随机抽样方法,对抽取的3 890名0~59岁普通人群开展调查与血样采集,应用酶联免疫吸附法（enzyme-linked immunosorbent assay,ELISA）检测抗-HEV IgG,采用χ2检验、精确二项式公式法与非条件Logistic回归等方法进行统计学分析。结果 武汉市0~59岁普通人群抗-HEV IgG标化阳性率为35.01%,男性标化阳性率与女性的差异无统计学意义（χ2=3.18,P=0.075）,随着年龄增长阳性率升高（χ2=542.32,P<0.001）,城区人群标化阳性率高于郊区（χ2=11.32,P=0.001）;18岁以上人群抗-HEV IgG多因素分析显示,男性、年龄较大者（30~59岁）、居住于城区、喜食鱼类的人群感染HEV的风险更高（均有P<0.05）。结论 武汉市普通人群HEV感染率较高,男性、年龄较大者（30~59岁）、居住于城区、喜食鱼类的居民是高危人群。     

湖州市病毒性肝炎血清流行病学调查

目的了解湖州市自然人群病毒性肝炎感染情况与流行病学特征。方法在湖州市按农村山区、平原水乡、城镇,随机抽取1 666名健康人为研究对象,用酶联免疫吸附试验检测血清甲型肝炎(甲肝)病毒抗体(抗-HAV)、乙型肝炎(乙肝)病毒表面抗原(HBsAg)、乙肝病毒表面抗体(抗-HBs)、乙肝病毒核心抗体(抗-HBc)、乙肝病毒e抗原(HBeAg)、乙肝病毒e抗体(抗-HBe)、丙型肝炎(丙肝)病毒抗体(抗-HCV)、戊型肝炎(戊肝)病毒抗体(抗-HEV),同时调查相关危险因素。结果湖州市自然人群的HAV、乙肝病毒(HBV)、HEV标化流行率分别为53.93%、36.47%、38.88%,抗-HCV阳性2例,未发现丁型肝炎病毒(HDV)感染者;HAV流行率与年龄呈正相关(r=0.944),城镇、平原水乡HAV流行率的差异有非常显著的统计学意义(P<0.01);HBV流行率<10岁儿童最低,为4.93%;HBsAg携带率为4.14%,<10岁儿童携带率为0;人群HBV标志物存在11种不同组合模式。HEV流行率随年龄增长而逐渐升高(r=0.993),城镇和平原水乡与山区HEV流行率的差异有非常显著的统计学意义(P<0.001),且存在家庭聚集性现象。结论湖州市病毒性肝炎主要流行型别为甲、乙、戊型,流行病学特征各不相同;HEV流行率较高,HBV流行率较低,HCV流行率低,未发现HDV感染者;HBsAg携带率低;乙肝疫苗接种效果明显。     

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。     

Seroprevalence of Hepatitis A and E Viruses Based on the Third Korea National Health and Nutrition Survey in Korea

Objectives

The purpose of this study was to investigate the seroprevalence of hepatitis A virus (HAV) and hepatitis E virus (HEV) in Korea during 2005.

Methods

Study subjects were selected from across Korea using a stratified multistage probability sampling design, and HAV and HEV seroprevalence was compared on the basis of sex, age, and residency. A total of 497 rural and urban people aged 10–99 years of age (mean ± SD age = 28.87 ± 17.63 years) were selected by two-stage cluster sampling and tested serologically for anti-HAV and anti-HEV IgG using an enzyme-linked immunosorbent assay.

Results

Among this population, the overall seroprevalence of HAV was 63.80% (55.21% aged in their 20s and 95.92% in their 30s, p < 0.01) and that of HEV was 9.40% (5.21% aged in their 20s and 7.14% in their 30s, p < 0.01). Seroprevalence also varied according to area of residence. HEV prevalence in rural areas was higher than that of urban regions based on the anti-HEV antibody, odds ratio 3.22 (95% confidence interval: 1.46–7.10, p < 0.01). There were no significant differences between male and female against anti-HAV/HEV antibodies.

Conclusion

Our study suggested that the seropositive rates of HAV and HEV might be related to age and environmental conditions.     

Hepatitis E Virus Seroprevalence among Adults, Germany

We assessed hepatitis E virus (HEV) antibody seroprevalence in a sample of the adult population in Germany. Overall HEV IgG prevalence was 16.8% (95% CI 15.6%–17.9%) and increased with age, leveling off at >60 years of age. HEV is endemic in Germany, and the lifetime risk for exposure is high.     

Seroprevalence of hepatitis E antibodies and risk profile of HEV seropositivity in The Netherlands, 2006-2007

SHepatitis E virus (HEV) is now considered an endemic pathogen in industrialized countries, leading to acute and sometimes chronic hepatitis, mostly in vulnerable people. The endemic sources are unclear. A survey in The Netherlands in 2006-2007 showed a 1·9% seroprevalence of HEV antibodies measured by ELISA and confirmed by immunoblot in a nationwide sample. Overall, in 134/7072 (1·9%) seropositive individuals, older age (P<0·01), being male (P<0·01), working with patients (P=0·03), working with animals (P=0·07), recent diarrhoeal complaints (P=0·07) and adhering to a religion that considers pigs unclean (P<0·01) were independently associated with seropositivity in multivariate analysis. Sub-analysis of 59/4022 (1·5%) anti-HEV antibody-positive subjects with probable endemic exposure showed independent association with youngest household member being aged <5 years or between 19 and <65 years (P=0·05) in multivariate analysis. These findings may contribute to a better understanding of the sources of endemic HEV exposure, and also highlight the need for systematic epidemiological and serological evaluation of new cases.     

湖北省HIV感染人群戊型肝炎流行病学调查

  目的  了解湖北省人类免疫缺陷病毒(human immunodeficiency virus,HIV)感染人群中戊型肝炎病毒(hepatitis E virus,HEV)的流行情况,为戊型肝炎和艾滋病防治提供有效依据。  方法  于2017年1~6月在湖北省不同地域收集335例HIV感染人群血清样本并进行抗-HEV IgM、抗-HEV IgG检测。  结果  335名HIV感染人群的抗-HEV IgG阳性率为41.49%(139/335),抗-HEV IgM阳性率为0.89%(3/335)。抗-HEV IgG阳性率与年龄无线性相关(χ_趋势2=0.756,P=0.385),各年龄组间差异均无统计学意义(均有P>0.05)。男女性抗-HEV IgG阳性率差异无统计学意义(χ2=0.085,P=0.771)。CD4 ≤ 200 cell/μl与CD4>200 cell/μl两组间抗-HEV IgG阳性率差异无统计学意义(χ2=1.016,P=0.314)。三例抗-HEV IgM阳性CD4值分别为222 cell/μl,446 cell/μl和198 cell/μl。湖北省东部(30.77%,32/1 041)与中部(47.92%,46/96)HIV感染人群抗-HEV IgG阳性率差异有统计学意义(χ2=6.169,P=0.013),与东南部抗-HEV IgG阳性率差异有统计学意义(χ2=5.034,P=0.025)。  结论  湖北省HEV病毒在HIV感染人群中流行度较高,需要进行进一步研究并及时采取有效措施进行预防控制。