急性戊型肝炎血清抗-HEV IgM、IgG和HEV RNA动态变化及其诊断价值

目的 分析急性戊型肝炎(AHE)患者血清抗-HEV IgM、抗HEV-IgG和HEV RNA变化规律。方法 2016年1月～2018年3月北京佑安医院就诊的AHE患者217例,动态检测血清抗-HEV IgM、抗HEV-IgG和HEV RNA变化。结果 首次检测血清抗-HEV IgM、IgG和HEV RNA均阳性31例(14.3%),抗-HEV IgM和IgG阳性99例(45.5%),抗-HEV IgM阳性8例(3.7%),抗-HEV IgG阳性72例(33.2%),抗-HEV IgM和HEV RNA均阳性3例(1.5%),抗-HEV IgG和HEV RNA均阳性2例(0.9%),抗-HEV IgM、IgG、HEV RNA均阴性2例(0.9%);在75例患者二次检测中,显示血清抗-HEV IgG阳性增多;在138例有准确的发病日期患者,在第1、2、3、4病周和第4病周后,血清HEV RNA阳性检出率分别为49.0%(25/51)、10.2%(6/59)、3.1%(1/32)、4.0%(1/25)和0.0%(0/0);血清抗-HEV IgM阳性检出率分别为70.6%(36/51)、69.5%(41/59)、65.6%(21/32)、48%(12/25)和56.5%(13/23);血清抗-HEV IgG阳性检出率分别为90.2%(46/51)、88.1%(52/59)、96.9%(31/32)、100%(25/25)和100.0%(23/23)。结论 AHE患者血清抗-HEV IgM、IgG和HEV RNA存在一定的变化规律,血清抗-HEV IgG阳性,结合典型的急性肝炎过程和排除其他病因后,可以诊断为AHE。     

湘潭农村居民结核潜伏感染现状及影响因素研究

目的 了解湖南省湘潭农村居民结核感染现状及其影响因素,为农村居民结核病防控提供科学的数据支撑。方法 采取整群随机抽样方法,抽取湘潭县中路铺镇6个自然村为研究现场,以这6个村5岁及以上常住人群为研究对象,采用γ-干扰素释放试验(IGRA)检测其结核分枝杆菌感染情况,运用单因素和多因素研究方法探讨其影响因素。结果 本研究应检人数5 440人,实检4 913人,受检率为90.3%。 受检人群潜伏感染率为26.0%(1 276/4 913),其中男性为29.8%(660/2 216),女性22.8%(616/2 697),差异有统计学意义(χ²=30.502,P<0.001);不同年龄组QuantiFERONTB Gold In-Tube (QFT)阳性率的差异有统计学意义(χ²=297.531,P<0.001),年龄越大结核分枝杆菌潜伏感染率越高。非条件二分类logistic回归分析显示:吸烟人群(OR=1.684,95%CI=1.462~1.939)、年龄46~60岁(OR=2.076,95%CI=1.748~2.465)、年龄>60岁(OR=3.152,95%CI=2.655~3.741);BMI<18.5 kg/m²:(OR=1.792,95%CI=1.397~2.300)、BMI 24~27.9 kg/m²:(OR=2.037,95%CI=1.563~2.656)、BMI≥28 kg/m²:(OR=2.597,95%CI=1.899~3.551)、有结核密切接触史(OR=1.214,95%CI=1.021~1.442)是结核潜伏感染的影响因素。结论 湘潭农村居民结核分枝杆菌感染率较高,感染的重点人群为老年人、吸烟人群、BMI异常人群以及有结核密切接触史的人群,需对以上重点人群采取针对性的措施。     

胶体金免疫层析法检测结核分枝杆菌特异性IgG/IgM抗体对结核病诊断的应用价值

目的 评价胶体金免疫层析法检测血清中结核分枝杆菌特异性IgG/IgM抗体在结核病诊断中的应用价值。方法 收集结核病患者和健康人的血清样本共332份及其背景资料,采用胶体金法检测血清中特异性结核抗体IgG/IgM,与临床诊断和细菌学检测结果比较,使用SPSS 22.0统计软件对结果进行比较分析,以P<0.05为差异具有统计学意义。结果 胶体金免疫层析法检测结核病患者中特异性结核抗体IgG/IgM的灵敏度为41.15%、特异性为91.67%,检测菌阳和菌阴结核病患者的敏感性分别为51.38%和33.77%。在全部结核病患者中,特异性结核抗体IgG/IgM检测检出率(41.15%)显著高于痰涂片法(18.84%)和痰菌培养法(36.15%)(P<0.05)。结核抗体检测、痰涂片法和痰培养法三种方法联合检测阳性率为61.54%,高于单种方法检测或其中两种方法联合检测。结论 胶体金免疫层析法检测血清中结核分枝杆菌抗体具有灵敏、特异、快速和简便等优点,可用于结核病的筛查,同时该方法也具有一定的局限性,敏感度和特异度有待进一步的提高,因此不可单独用于诊断结核病,可配合痰细菌学、影像学和临床表现等进行辅助诊断。     

孝感地区孕妇感染戊型肝炎病毒流行病特征和母婴HEV IgG传递率调查

目的调查湖北省孝感地区孕妇戊型肝炎病毒感染状况及流行特征、母婴抗-HEV IgG传递率和抗-HEV IgG在婴幼儿体内的消长。方法孕妇446例和相对应年龄的普通健康女性463例,收集其人口统计学数据并采集其血清标本;采集20例抗-HEV IgG阳性孕妇分娩的新生儿血清,并追踪收集25例抗-HEV IgG阳性婴幼儿血清(每两月采集一次,共采集7次),采用ELlSA法检测血清抗-HEV IgG和抗-HEV IgM,对抗-HEV IgM阳性标本进行HEV基因分型。结果对照人群抗-HEV IgG阳性率19.22%(89/463);抗-HEV IgM阳性率1.08%(5/463)),孕妇抗-HEV IgG阳性率为19.73%(88/446),抗-HEV IgM阳性率1.57%(7/446),两组相比差异无统计学意义(P0.05)。孕妇和对照人群随年龄增长抗-HEV IgG阳性率增高,26-30年龄段孕妇抗-HEV IgG阳性率高于对照人群。农民孕妇抗-HEV IgG阳性率高于其他职业孕妇。母婴抗-HEV IgG传递率为80.00%(16/20)。追踪检测婴幼儿抗-HEV IgG体内存在时间为4~12月。孕妇和对照人群中各有1个HEV RNA阳性标本,HEV基因序列同源性为99.34%,基因型为IV d亚型。结论孝感地区孕妇人群存在HEV散发感染,以无症状的隐性感染为主;抗-HEV IgG母婴传递率较高,但该抗体在婴幼儿体中存在的时间较短。     

结核分枝杆菌CFP10-ESAT6融合蛋白免疫小鼠效果初步评价

目的 融合表达和纯化结核分枝杆菌(MTB)CFP10-ESAT6(CE),初步评价免疫效果。方法 构建pET32a(+)-CE重组质粒,E.coli BL21(DE3)中融合表达,Ni-NTA层析纯化。用CE加铝佐剂,50 μg CE/只/次,分3次免疫BALB/c小鼠。ELISA测定血清IgG抗体;ELISpot与Luminex检测细胞因子,进行MTB体外生长抑制试验。卡介苗(BCG)为阳性对照。结果 CE免疫小鼠,能诱导产生高效价的IgG、IgG1和IgG2a,且IgG1(t=19.1,P<0.000 1)和IgG2a(t=8.7,P<0.000 1)抗体水平均高于BCG组。CE组与BCG组诱导产生的分泌IFN-γ的斑点形成细胞(SFC)数量差异无统计学意义(t=0.4, P>0.05),但诱导分泌IL-4的SFC数量高于BCG组(t=8.0, P<0.000 1)。CE组诱导分泌GM-CSF(t=8.4,P<0.05)、IL-6(t=8.3,P<0.05)、IL-10(t=2.5,P<0.05)和IL-4(t=7.0,P<0.05)均高于BCG组,而CE组诱导分泌IFN-γ(t=1.4,P>0.05)、TNF-α(t=1.8,P>0.05)、IL-2(t=2.0,P>0.05)、IL-12(t=0.9,P>0.05)和IL-17(t=1.3,P>0.05)均与BCG组相似,差异无统计学意义。CE组小鼠脾细胞的MTB体外生长抑制结-果与BCG组相似(t=0.8,P>0.05)。结论 CE免疫小鼠可诱导较强的Th1与Th2混合型免疫反应,且有较强的体外抑制MTB生长的能力,表明CE具有良好的结核疫苗研制应用价值。     

福建省人感染H7N9禽流感诊疗特征分析

目的 分析福建省人感染H7N9禽流感诊疗特征,以期为疾病防控和临床救治提供参考。方法 采用SPSS 23.0、SAS9.2软件对福建省人感染H7N9禽流感诊疗特征进行描述性分析。结果 福建省共报告108例病例,死亡28人,病死率25.93%。病例从发病到就诊、住院、确诊和抗病毒治疗中位数分别为3 d、5 d、7 d和6 d,死亡病例组发病至死亡中位数16 d,从发病至实验室确诊比早期提前1 d。一半以上病例没有在5 d内使用抗病毒治疗药物,死亡风险可能没有得到有效降低。46.3%的病例伴有基础疾病,随年龄增长患基础疾病和重症率增加(Z=4.75,P<0.01; Z=5.07,P<0.01)。男女病死率比较,差异无统计学意义(χ²=28.37,P<0.01),各年龄组病死率比较,差异无统计学意义(χ²=2.23,P=0.53)。患心血管疾病(OR=2.60,95%CI:1.06~6.39)、出现肺炎(OR=1.27,95%CI:1.13~1.42)、重症(OR=1.24,95%CI:1.13~1.42)、需进ICU(OR=3.80,95%CI:1.20~11.99)、合并细菌感染需要使用抗生素(OR=1.19,95%CI:1.08~1.32)和需使用激素(OR=7.47,95%CI:1.64~33.95)等因素增加病死风险。结论 福建省人感染H7N9禽流感病例诊断能力较早期有所提高,抗病毒治疗仍不及时。当患者伴有心血管疾病和需要使用激素等危险因素时,应积极加强救治,降低病死率。     

HEV核酸、抗原、抗体对HEV感染的诊断价值

目的探讨HEV核酸(HEV RNA)、HEV抗原(HEV Ag)、HEV抗体(HEV IgM抗体和HEV IgG抗体)在临床诊断HEV感染中的作用。方法收集在北京大学人民医院进行HEV IgM抗体和HEV IgG抗体检测的13992例标本,其中1924例HEV IgM抗体或HEV IgG抗体阳性。分别采用荧光PCR法进行HEV RNA和基因型检测,酶联免疫吸附试验方法进行HEV Ag、HEV IgM抗体和HEV IgG抗体检测,并检测ALT、AST、TBil和DBil水平。计量资料两组间比较采用Mann-Whitney U检验。结果1924例标本中HEV IgM抗体阳性152例(7.9%),HEV IgG抗体阳性1897例(98.6%),HEV RNA阳性62例(3.2%),HEV Ag阳性55例(2.9%)。HEV IgM抗体阳性组中HEV RNA阳性率为40.8%(62/152),HEV Ag阳性率为36.2%(55/152)。HEV RNA阳性组中HEV Ag阳性率为88.7%(55/62)。HEV RNA阳性组(n=62)ALT、AST、TBil、DBil水平高于HEV RNA阴性组(n=90)(Z值分别为-7.609、-6.942、-5.815、-6.130,P值均<0.001),HEV Ag阳性组(n=55)ALT、AST、TBil、DBil水平明显高于HEV Ag阴性组(n=97)(Z值分别为-6.413、-5.786、-5.199、-5.545,P值均<0.001)。巢式PCR扩增测序结果显示58例HEV RNA阳性,4例阴性。HEV IgG抗体阳性高水平明显降低HEV Ag检测的S/CO值,甚至出现阴性结果。结论与HEV抗体相比,HEV Ag可以提高戊型肝炎的诊断水平,具有一定的临床意义;高水平的转氨酶或胆红素可以辅助诊断HEV感染;高水平的HEV IgG抗体会降低HEV Ag检测值,检测时应注意HEV Ag阴性时HEV IgG抗体值。     

重庆地区计划妊娠妇女弓形虫感染现况调查

目的 了解重庆地区计划妊娠妇女弓形虫感染现况,为本区域出生缺陷一级干预提供参考依据。方法 采用按比例多阶段分层整群随机抽样方法抽取11 953例计划妊娠妇女进行问卷调查,并采集静脉血,用ELISA法检测弓形虫特异性抗体。结果 11 953例妇女中,弓形虫IgM阳性71例,阳性率0.59%;IgG阳性771例,阳性率6.45%。一圈地区弓形虫IgM阳性率、IgG阳性率均高于渝东南和渝东北地区( χ²=35.28,P<0.000 1;χ²=82.65,P<0.000 1)。弓形虫IgM阳性率随文化程度升高而升高(χ²_趋势=3.25,P=0.0011)。不同职业妇女弓形虫IgM阳性率、IgG阳性率不同(χ²=13.93,P=0.016 0;χ²=15.58,P=0.008 1),IgM阳性率和IgG阳性率均公职人员最高。既往有不良妊娠结局史的计划妊娠妇女,弓形虫IgM阳性率、IgG阳性率高于对照组(χ²=6.85,P=0.008 9;χ²=59.25,P<0.000 1)。密切接触猫的计划妊娠妇女弓形虫IgM阳性率和对照组无统计学差异(χ²=0.23,P=0.628 6),IgG阳性率高于对照组(χ²=9.95,P=0.001 6)。结论 重庆地区计划妊娠妇女弓形虫感染率处于较低水平,不良妊娠结局与弓形虫感染有关。     

我国蜱和人群中TBEV流行情况的Meta分析

目的 通过评价蜱、人群中蜱传脑炎病毒阳性率及血清抗体阳性率的情况,分析蜱传脑炎在我国的流行特点,明确我国现行蜱传脑炎预防控制措施疫苗接种的重要意义,为该病的预防控制提供科学依据。方法 检索PubMed、万方、维普和知网数据库搜集2000-2019年发表的关于蜱中蜱传脑炎病毒阳性率和人血清学调查的文章,通过Meta分析方法利用Stata15软件对选定的11篇和12篇相关文献进行汇总和分析,得到蜱传脑炎在我国蜱和人群中的流行特点。结果 2000-2019年我国TBEV阳性蜱主要分布在吉林、黑龙江和内蒙古。不同蜱种中TBEV阳性率不同,森林革蜱中TBEV阳性率最高为5%(95%CI:2%~10%,P<0.05)。人群特征分析显示:男性抗体阳性率高于女性,林区工人、军人和农民易感染。不同地区人群血清抗体阳性率差异很大,新疆地区的抗体阳性率最高为14%(95%CI:9%~21%,P<0.05)。结论 我国TBEV流行多在东北地区,阳性蜱以森林草蜱为主,感染人群多为林区工人、军人和农民。     

北京东北部山区人群嗜吞噬细胞无形体血清流行病学调查

目的 了解北京东北部山区人群嗜吞噬细胞无形体的感染状况,为制定相应的防控策略提供依据。方法 在北京密云与怀柔区采集人群血清,采用间接免疫荧光法检测嗜吞噬细胞无形体IgG抗体,进行血清流行病学调查。结果 801份血清中嗜吞噬细胞无形体IgG抗体阳性者106份,阳性率13.23%,其中密云区为13.48%,怀柔区为12.70%,差异无统计学意义(P>0.05)。结论 北京密云与怀柔区正常人群中均有嗜吞噬细胞无形体感染的存在,应加强人粒细胞无形体病的监测和防控工作。     

Hepatitis E virus infection may be transmitted through blood transfusions in an endemic area

AIM: To address the issue of whether or not hepatitis E virus (HEV) is transmitted parenterally. METHODS: We conducted a retrospective study which involved 145 multiple transfused patients and 250 healthy controls. A prospective study was also undertaken involving 50 hospitalized patients, 25 of whom were transfused with 107 blood units, while the other 25 did not receive any transfusions. RESULTS: In our retrospective study, markers of acute HEV infection (IgM anti-HEV and HEV RNA) were detected in a significantly higher number of multiple transfused patients (13 of 145) compared to controls (two of 250) (P < 0.001; OR = 12.21 [95% confidence interval: 2.71-54.70]). All 13 HEV-infected patients had been transfused at least once in a 3-month period before testing. Overall, patients positive for any of the HEV markers (IgG, IgM or HEV RNA) had received more blood transfusions, had higher occurrence of icteric disease and higher serum alanine aminotransferase levels. In our prospective study, IgG anti-HEV was detected in 11 of 107 donor samples, three of 25 patients in their pretransfusion samples (one sample was positive for IgM anti-HEV as well) and two of 25 control patients. Post-transfusion HEV infection developed in three of 22 susceptible (IgG anti-HEV negative) transfused patients; the infection was traced to their four respective donors who were asymptomatic, HEV RNA positive (4/4) and IgM anti-HEV positive (3/4). In contrast, none of the non-transfused patients developed HEV infection during the follow-up period. CONCLUSION: Frequent transmission of HEV by blood transfusion places recipients at risk and warrants redefining of the donor screening policy by blood banks, especially in endemic areas.     

The Risk of Transfusion-Transmitted Hepatitis E Virus: Evidence from Seroprevalence Screening of Blood Donations

Throughout the world, there has been growing concern over the risk of hepatitis E virus (HEV) transmission via blood transfusion. The present study screened blood donor samples for anti-HEV immunoglobulin M (IgM) and immunoglobulin G (IgG). The prevalence of HEV infection was assessed on a total of 1,003 archived serum samples obtained from the National Blood Centre, Malaysia. The samples were collected from healthy blood donor from Klang Valley between 2017 and 2018. All samples were tested for IgM and IgG antibodies to HEV using enzyme-linked immunosorbent assays (ELISA). HEV-specific IgG antibodies were detected in 31/1003 (3.1%; 95% confidence interval [CI] 2.1%–4.4%) and IgM in 9/1003 (0.9%; 95% CI 0.4%–1.7%) samples. In bivariate analysis, there was no significant difference in the prevalence of anti-HEV IgG with respect to gender and district of origin. Although not statistically significant, males had higher odds of having anti-HEV IgG than females (odds ratio [OR] = 2.86; 95% CI 0.95–8.64). All anti-HEV IgG positive individuals were people of Chinese descent. Anti-HEV IgG increased significantly with age, from 0.6% (95% CI 0.1%–2.6%) of 18–30-year-old donors to 7.4% (95% CI 2.7%–17.0%) of donors older than 50 years and was highest among non-professional workers (5.3%; 95% CI 2.5%–10.5%). Increasing age and a non-professional occupation remained significant predictors for anti-HEV IgG in the multivariable analysis. Screening of blood donations for HEV in Malaysia is important to safeguard the health of transfusion recipients. The higher rates of HEV infection in blood from older donors and donors who are non-professional workers may provide insights into targeted groups for blood screening.     

献血员戊型肝炎病毒亚临床感染情况调查

目的了解献血员中戊型肝炎病毒(HEV)亚临床感染情况。方法对2002年7～8月向北京市血液中心义务献血的所有人员进行整群抽样，检测抗-HEV IgM和IgG抗体。结果北京献血员中抗-HEV IgM阳性率为1．74％，其丙氨酸氨基转移酶(ALT)异常比例高于抗-HEV IgM阴性献血员。ALT异常与HEV相关的比例为2．68％，与HBV相当，但高于丙型肝炎病毒。结论献血员中存在HEV亚临床感染者，并且是献血员中ALT异常的原因之一。     

Consecutive evaluation of immunoglobulin M and G antibodies against hepatitis E virus

Hepatitis E virus (HEV) infection is sporadic in the Guangzhou city southern China. However, the evaluation of antibodies to HEV during consecutive time periods after infection has not been reported. We utilized enzyme immunosorbent assay (ELISA) to detect IgM and IgG anti-HEV in consecutive serum specimens from patients with acute hepatitis E and compared that data with detection rates of IgM and IgG anti-HAV in patients with acute hepatitis A. IgM anti-HEV can be detected as early as 4 days after onset of disease symptoms in some patients. The detection rate of IgM anti-HEV is significantly higher in specimens collected within 4 weeks (95%) of onset than in those specimens collected 4 to 18 weeks after onset (67.6%) (P<0.005). IgM anti-HEV had a similar pattern to IgM anti-HAV and can be used as a marker of acute HEV infection. In contrast with IgG anti-HAV, 56.8% of the specimens did not contain detectable levels of IgG anti-HEV (P<0.005). One should be cautioned against making a diagnosis of HEV infection solely by the currently available assays for IgG anti-HEV. In conclusion, IgM anti-HEV can be used as a reliable and sensitive marker for recent HEV infection, but serum specimens should be collected within 4 weeks after onset of symptoms to avoid false-negative results. In contrast, we should be aware of the failure to develop IgG anti-HEV in some patients. These patients carry the risk of reinfection.     

Prevalence and risk factors for hepatitis E virus infection in blood donors: a nationwide survey in Italy, 2017 to 2019

BackgroundIn high-income countries, hepatitis E virus (HEV) infection is mainly a zoonosis. However, it is also transfusion-transmissible and some countries, but not Italy, have introduced HEV screening for blood donations.AimWe assessed HEV infection prevalence and risk factors in a nationwide sample of Italian blood donors.MethodsWe selected 107 blood establishments (BE) distributed in the 20 Italian regions by a stratified two-stage design and invited them to participate in the study. Donors were tested for anti-HEV IgG and IgM and HEV RNA. Sociodemographic data and risk factors were collected through a questionnaire.ResultsOverall, 60 BE from 60 provinces in 19 Italian regions joined the study. We assessed HEV markers in 7,172 blood donors, of whom 6,235 completed the questionnaire. Overall crude and adjusted anti-HEV IgG prevalences were 8.3% and 5.5%, respectively. Overall anti-HEV IgM prevalence was 0.5%, while no blood donor was HEV RNA-positive. Anti-HEV IgG prevalence varied widely among regions (range: 1.3%–27.20%) and hyperendemic prevalences (> 40%) were detected in some provinces in two regions. Older age (AOR = 1.81; 95% CI: 1.36–2.41), foreign nationality (AOR = 2.77; 95% CI: 1.06–7.24), eating raw pork liver sausages (AOR = 2.23; 95% CI: 1.55–3.20) and raw homemade sausages (AOR = 3.63; 95% CI: 2.50–5.24) were independent infection predictors.ConclusionItalian blood donors showed a low to moderate HEV seroprevalence. High levels in some regions and/or provinces were mainly attributable to eating habits. Prevention should include avoiding consumption of raw or undercooked meat and safe production of commercial pork products.     

Anti-HEV IgG Avidity Testing: Utility for Diagnosing Acute and Resolved Genotype 3 Infections

European Association of the Study of the Liver (EASL) guidelines specify HEV RNA, as well as anti-HEV IgG and IgM as positive markers for acute HEV infection. HEV RNA assay sensitivity limitations may lead to false negative test results in patients with low levels of viremia. Moreover, anti-HEV IgM positivity is not a reliable indicator for distinguishing between acute and resolved infections given the ability of this antibody to persist several months after a resolved infection. Our study aims were to assess HEV IgG avidity for diagnosing acute and resolved infections, regardless of the anti-HEV IgM serostatus, and examine assay reliability when evaluating different genotype 3 (GT3) HEV subtypes. Patient serum samples (n = 104) were tested for HEV IgG avidity by utilizing the DIA.PRO kit on a DSX automated instrument. Among patients identified with acute HEV infections, 32 were infected with GT3: GT3c (n = 5), GT3e (n = 8), 3f (n = 17) and GT3-unsubtyped (n = 2). Avidity sensitivity was 91.2% and specificity was 100%. For patients with long-lasting anti-HEV IgM persistence, an Avidity Index >70% was observed. Thus, the DIA.PRO avidity assay may be utilized to distinguish between recently acquired and resolved HEV GT3 infections. However, for equivocal results (Avidity Index > 40–70%), HEV RNA molecular testing will be required to confirm a recent infection.     

Epidemic of hepatitis E in a military unit in Abbotrabad,Pakistan

An outbreak of hepatitis caused by hepatitis E virus (HEV) in Abbottabad, Pakistan was traced to fecal contamination of a water system. Of 109 men hospitalized with hepatitis, 104 (95%) had serologic evidence of acute hepatitis E (IgM antibody to HEV [anti-HEV]), three (3%) probably had acute hepatitis E (high titers of IgG anti-HEV without IgM), and two had acute hepatitis A. Among a subset of 44 men with acute hepatitis E from whom three serum specimens were obtained over a four-month period, the anti-HEV IgG geometric mean titers (GMTs) decreased from 1,519 during the outbreak to 657 at four months. The IgM anti-HEV was detected in 40 (91%) of 44 sera obtained at admission (GMT = 533 during acute disease), but in only six (14%) four months later. The prevalence of anti-HEV in this population before the outbreak was estimated to be 30%. The presence of IgG anti-HEV appeared to protect against clinical hepatitis or development of serologic evidence of new infection with HEV. This is the second major epidemic of hepatitis E in the Pakistani military confirmed by an anti-HEV enzyme-linked immunosorbent assay (ELISA). Evidence that pre-existing antibody as measured by this ELISA protects against disease is important for assessment of vaccine development.     

Seroepidemiology of Hepatitis E Virus Infection in General Population in Rural Durango,Mexico

Background:

The seroepidemiology of hepatitis E virus (HEV) infection in rural areas in Mexico has been poorly studied.

Objectives:

The aim of the study was to determine the seroprevalence and correlates of anti-HEV IgG antibodies in adults in rural areas in Durango, Mexico.

Materials and Methods:

We performed a cross-sectional study to determine the frequency of anti-HEV IgG antibodies in 273 adults living in rural Durango, Mexico using an enzyme-linked immunoassay. In addition, we searched for an association of HEV exposure with the socio-demographic and behavioral characteristics of the subjects studied.

Results:

One hundred (36.6%) of the 273 rural adults (mean age: 39.85 ± 17.15 years) had anti-HEV IgG antibodies. Multivariate analysis of socio-demographic and behavioral characteristics of the participants showed that HEV exposure was associated with increasing age (OR = 1.04; 95% CI: 1.04-1.05; P < 0.001), consumption of untreated water (OR = 1.92; 95% CI: 1.06-3.46; P = 0.03), and availability of water at home (OR = 1.87; 95% CI: 1.07-3.27; P = 0.02). In contrast, other socio-demographic and behavioral characteristics including educational level, occupation, socio-economic status, foreign travel, consumption of unwashed raw fruits, consumption of raw or undercooked meat and raising animals did not show associations with HEV exposure.

Conclusions:

The seroprevalence of HEV infection found in rural Durango is higher than those reported in other Mexican populations. Consumption of untreated water is an important factor for HEV exposure in rural areas in Durango. The correlates of HEV seropositivity found in the present study can be used for an optimal planning of preventive measures against HEV infection.