Centre for Molecular Epidemiology and Translational Research, Institute for Global Health, University College London, London, UK.
MRC Clinical Trials Unit, University College London, London, UK.
J Glob Health. 2020 Jun;10(1):010404. doi: 10.7189/jogh.10.010404.
Epstein-Barr virus (EBV) is an important human pathogen; it infects >90% people globally and is linked to infectious mononucleosis and several types of cancer. Vaccines against EBV are in development. In this study we present the first systematic review of the literature on risk factors for EBV infection, and discuss how they differ between settings, in order to improve our understanding of EBV epidemiology and aid the design of effective vaccination strategies.
MEDLINE, Embase, and Web of Science were searched on 6 March 2017 for observational studies of risk factors for EBV infection. Studies were excluded if they were published before 2008 to ensure relevance to the modern day, given the importance of influencing future vaccination policies. There were no language restrictions. After title, abstract and full text screening, followed by checking the reference lists of included studies to identify further studies, data were extracted into standardised spreadsheets and quality assessed. A narrative synthesis was undertaken.
Seventy-seven papers met our inclusion criteria, including data from 31 countries. There was consistent evidence that EBV seroprevalence was associated with age, increasing throughout childhood and adolescence and remaining constant thereafter. EBV was generally acquired at younger ages in Asia than Europe/North America. There was also compelling evidence for an association between cytomegalovirus infection and EBV. Additional factors associated with EBV seroprevalence, albeit with less consistent evidence, included ethnicity, socioeconomic status, other chronic viral infections, and genetic variants of HLA and immune response genes.
Our study is the first systematic review to draw together the global literature on the risk factors for EBV infection and includes an evaluation of the quality of the published evidence. Across the literature, the factors examined are diverse. In Asia, early vaccination of infants would be required to prevent EBV infection. In contrast, in Western countries a vaccine could be deployed later, particularly if it has only a short duration of protection and the intention was to protect against infectious mononucleosis. There is a lack of high-quality data on the prevalence and age of EBV infection outside of Europe, North America and South-East Asia, which are essential for informing effective vaccination policies in these settings.
爱泼斯坦-巴尔病毒（EBV）是一种重要的人类病原体；它感染了全球超过 90%的人群，与传染性单核细胞增多症和几种类型的癌症有关。针对 EBV 的疫苗正在研发中。在这项研究中，我们首次对 EBV 感染的危险因素进行了系统的文献回顾，并讨论了它们在不同环境中的差异，以增进我们对 EBV 流行病学的认识，并帮助设计有效的疫苗接种策略。
2017 年 3 月 6 日，我们在 MEDLINE、Embase 和 Web of Science 上搜索了有关 EBV 感染危险因素的观察性研究。为了确保与现代相关，即考虑到未来疫苗接种政策的影响，我们排除了发表时间早于 2008 年的研究。没有语言限制。经过标题、摘要和全文筛选，以及对纳入研究的参考文献进行检查以确定其他研究后，我们将数据提取到标准化的电子表格中，并进行质量评估。采用叙述性综合方法进行分析。
77 篇论文符合我们的纳入标准，其中包括来自 31 个国家的数据。有一致的证据表明，EBV 血清阳性率与年龄有关，在儿童和青少年时期逐渐增加，并在此后保持不变。在亚洲，EBV 通常在较年轻时被感染，而在欧洲/北美则较晚。巨细胞病毒感染与 EBV 之间存在关联，这也是一个强有力的证据。此外，还有一些证据表明，种族、社会经济地位、其他慢性病毒感染以及 HLA 和免疫反应基因的遗传变异与 EBV 血清阳性率有关，但证据并不一致。
我们的研究是首次对 EBV 感染危险因素的全球文献进行系统综述，并对已发表证据的质量进行了评估。在文献中，所检查的因素多种多样。在亚洲，需要对婴儿进行早期疫苗接种以预防 EBV 感染。相比之下，在西方国家，疫苗可以更晚部署，特别是如果疫苗的保护期较短，并且目的是预防传染性单核细胞增多症。欧洲、北美和东南亚以外地区缺乏 EBV 感染的流行率和年龄的高质量数据，这对于在这些地区制定有效的疫苗接种政策至关重要。
