Prevalence and Epidemiology of Hepatitis E Virus in the United States

描述（由申请人提供）：戊型肝炎病毒（HEV）是导致发展中国家临床肝炎大规模暴发和发展中国家大量散发临床肝炎的病原。尽管它无处不在，但在人群中维持流行间HEV的机制仍然知之甚少。最近发现了该病毒的大型人畜共患宿主，通过受污染的肉制品传播的戊型肝炎食源性传播，以及工业化国家中大量戊型肝炎血清流行率，这些都强化了人们对戊型肝炎流行病学知之甚少的事实。在本申请中，我们建议使用美国国立卫生研究院（NIH）肝炎病毒科开发的高度准确且经过验证的ELISA检测，检测作为第三次全国健康与营养调查（NHANES III）的一部分收集的储存血清样本中是否存在抗hev IgG。NHANES III是疾病控制和预防中心（CDC）在1988- 1994年间对美国所有非收容人口进行的一项有代表性的调查，包括对参与者的人口统计、职业和食品消费特征的详细评估。所有抗戊肝病毒检测将在约翰霍普金斯大学传染病项目（IDP）实验室使用美国国立卫生研究院的检测方法进行。我们将通过在美国国立卫生研究院肝炎病毒科进行2%的样本重新测试来验证我们的结果，并与美国疾病控制与预防中心国家卫生统计中心和病毒性肝炎司合作进行中期分析。我们期望拟议项目的结果能够准确估计美国HEV抗体的总体流行情况，并深入了解不同年龄、性别和种族/民族群体的疾病暴露率。此外，我们期望有很好的能力来最终检验HEV血清阳性与动物接触、肉类消费和社会经济地位之间假定的流行病学关联。该项目将产生迄今为止最全面的戊型肝炎流行病学评估，并将有助于确定可能受益于新开发的高效戊型肝炎疫苗的高危人群。

DESCRIPTION (provided by applicant): Hepatitis E virus (HEV) is the etiologic agent responsible for large outbreaks of clinical hepatitis in developing countries and a large proportion of sporadic clinical hepatitis in developing countries. Despite its omnipresence, the mechanism for maintenance of inter-epidemic HEV in populations remains poorly understood. The recent discoveries of a large zoonotic reservoir for the virus, food-borne transmission of HEV via contaminated meat products, and substantial HEV seroprevalence in industrialized countries have reinforced how little is known about the epidemiology of HEV. In this application we propose to test stored serum samples collected as a part of the third National Health and Nutrition Survey (NHANES III) for the presence of anti-HEV IgG using a highly accurate and validated ELISA assay developed at the Hepatitis Viruses Section, National Institutes of Health (NIH). NHANES III was a representative survey of the entire non-institutionalized United States population conducted from 1988-94 by the Centers for Disease Control and Prevention (CDC) and included detailed assessment of demographic, occupational, and food consumption characteristics of its participants. All anti-HEV testing will be conducted at the Johns Hopkins Infectious Disease Program (IDP) laboratories using the NIH assay. We will validate our results via a two percent sample re-testing at the Hepatitis Virus Section, NIH, and conduct interim analyses in collaboration with the National Center for Health Statistics, CDC and the Division of Viral Hepatitis, CDC. We expect the results of the proposed project to give a precise estimate of overall HEV antibody prevalence in the United States, as well give substantial insight into rates of disease exposure among various age, gender, and racial/ethnic groups. Additionally, we expect to have excellent power to conclusively test postulated epidemiologic associations between HEV seropositivity and contact with animals, meat consumption, and socioeconomic status. This project will produce the most comprehensive assessment of HEV epidemiology available to date, and will aid in the identification of at-risk groups that may benefit from the newly developed and highly efficacious HEV vaccine.