Epidemiology of Hep E Virus Infections in Bangladesh

描述（由申请人提供）：戊型肝炎病毒（HEV）感染引起 严重的发病率和死亡率，尤其是孕妇。几 基于人群的研究已经描述了HEV流行病学的特征。提出了一种 一项为期两年、多部分、以人群为基础的研究，以描述流行病学 并量化孟加拉国农村地区HEV感染和疾病的负担 （Matlab District）这些研究将嵌套在105，000人的人群中 自1966年以来一直受到严密的纵向健康监测。这种独特 由国际腹泻病中心维护的研究环境 研究，代表了最准确和最古老的人口健康 发展中国家的监控。有证据表明孟加拉国是HEV 地方性的，但没有已知的研究已经检查了戊型肝炎。年龄别 将使用以下方法确定HEV的IgM和IgG抗体的人群流行率： 来自Matlab队列的1030个个体的随机样本。很大比例 15岁以下的人群，允许描述HEV抗体 使用改进的、可靠的检测方法对儿童的流行率进行检测。数据将 在基线、12个月和18个月时采集。戊型肝炎病毒感染的发病率和 将根据HEV血清转换率计算疾病， 监测系统记录中的肝炎疾病报告。的比率 将估计无症状HEV感染到临床HEV。嵌套 还建议在18个月期间进行病例对照研究，以确定 与散发性HEV疾病相关的潜在危险因素。污染的水 已知会促使HEV爆发，但散发性HEV的风险因素是 未知一种视觉算法将识别出潜在的HEV病例， 感染仅入组抗HEV 1 gM阳性病例。2例未接受过HEV治疗 对照组将与病例年龄匹配。一份调查问卷将评估潜在的 与HEy事件相关的行为、动物和环境危险因素。 将使用多元逻辑回归对风险因素进行建模。利用地理信息系统， 将对病例进行空间或时间聚类分析。病毒分离株来自 将对急性病例进行测序，以进行孟加拉国HEy的系统发育分析。 这些在明确定义的东南亚人群中进行的研究将提供一个 高风险地区地方性和流行性HEV的综合流行病学特征 人口，并可能构成未来预防干预措施的基础， 疫苗试验。

DESCRIPTION (provided by applicant): Hepatitis E virus (HEV) infections cause serious morbidity and mortality, especially in pregnant women. Few population-based studies have characterized HEV epidemiology. Proposed is a two-year, multi-component, population-based study to describe the epidemiology and quantify the burden of HEV infections and disease in rural Bangladesh (Matlab District). These studies will be nested within a population of 105,000 under intensive longitudinal health surveillance since 1966. This unique research setting, maintained by the International Center for Diarrheal Disease Research, represents the most accurate and oldest population health surveillance in the developing world. Evidence suggests Bangladesh is HEV endemic, yet no known studies have examined HEV there. The age-specific population prevalence of 1gM and lgG antibodies to HEV will be determined using a random sample of 1030 individuals from the Matlab cohort. A large proportion of the population is under age 15, allowing a description of HEV antibody prevalence among children using improved, reliable assays. Data will be collected at baseline, 12, and 18 months. Incidence of HEV infection and disease will be calculated from HEV seroconversion rates and by extracting reports of hepatitis disease from surveillance system records. A ratio of asymptomatic HEV infections to clinical HEV will be estimated. A nested case-control study is also proposed during the 18-month period to identify potential risk factors associated with sporadic HEV disease. Contaminated water is known to precipitate HEV outbreaks, but risk factors for sporadic HEV are unknown. A visual algorithm will identify potential HEV cases near the time of infection. Only anti-HEV 1gM positive cases will be enrolled. Two HEV-naive controls will be age-matched to a case. A questionnaire will assess potential behavioral, animal and environmental risk factors associated with incident HEy. Multiple logistic regression will be used to model risk factors. Using GIS, cases will be analyzed for spatial or temporal clustering. Virus isolates from acute cases will be sequenced for a phylogenetic analysis of Bangladesh HEy. These studies in a well-defined South-East Asian population will provide a comprehensive epidemiologic profile of endemic and epidemic HEV in a high risk population, and could form the basis for future preventive interventions, such as vaccine trials.