Late-onset Alzheimer's disease (AD) is the most prevalent cause of dementia among older adults, yet more than a century of research has not determined why this disease develops. One prevailing hypothesis is that late-onset AD is caused by infectious pathogens, an idea widely studied in both humans and experimental animal models. This review examines the infectious AD etiology hypothesis and summarizes existing evidence associating infectious agents with AD in humans. The various mechanisms through which different clinical and subclinical infections could cause or promote the progression of AD are considered, as is the concordance between putative infectious agents and the epidemiology of AD. We searched the PubMed, Web of Science, and EBSCO databases for research articles pertaining to infections and AD and systematically reviewed the evidence linking specific infectious pathogens to AD. The evidence compiled from the literature linking AD to an infectious cause is inconclusive, but the amount of evidence suggestive of an association is too substantial to ignore. Epidemiologic, clinical, and basic science studies that could improve on current understanding of the associations between AD and infections and possibly uncover ways to control this highly prevalent and debilitating disease are suggested.

中文翻译：

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感染会导致阿尔茨海默病吗？


晚发性阿尔茨海默病 (AD) 是老年人痴呆症最常见的原因，但一个多世纪的研究尚未确定这种疾病发生的原因。一个流行的假设是，迟发性 AD 是由传染性病原体引起的，这一观点在人类和实验动物模型中得到了广泛研究。这篇综述探讨了传染性 AD 病因学假说，并总结了传染源与人类 AD 相关的现有证据。考虑了不同的临床和亚临床感染可能导致或促进 AD 进展的各种机制，以及假定的感染原与 AD 流行病学之间的一致性。我们在 PubMed、Web of Science 和 EBSCO 数据库中检索了有关感染和 AD 的研究文章，并系统地回顾了将特定传染性病原体与 AD 联系起来的证据。从文献中收集到的将 AD 与感染原因联系起来的证据尚无定论，但表明这种关联的证据数量太多，不容忽视。建议进行流行病学、临床和基础科学研究，以增进目前对 AD 与感染之间关联的理解，并可能揭示控制这种高度流行且使人衰弱的疾病的方法。