Division of Infectious Diseases, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA.
Laboratory of Virology, Division of Intramural Research, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, USA.
J Infect Dis. 2023 Nov 13;228(Suppl 7):S465-S473. doi: 10.1093/infdis/jiad352.
The origins of Ebola disease outbreaks remain enigmatic. Historically outbreaks have been attributed to spillover events from wildlife. However, recent data suggest that some outbreaks may originate from human-to-human transmission of prior outbreak strains instead of spillover. Clarifying the origins of Ebola disease outbreaks could improve detection and mitigation of future outbreaks.
We reviewed the origins of all Ebola disease outbreaks from 1976 to 2022 to analyze the earliest cases and characteristics of each outbreak. The epidemiology and phylogenetic relationships of outbreak strains were used to further identify the likely source of each outbreak.
From 1976 to 2022 there were 35 Ebola disease outbreaks with 48 primary/index cases. While the majority of outbreaks were associated with wildlife spillover, resurgence of human-to-human transmission could account for roughly a quarter of outbreaks caused by Ebola virus. Larger outbreaks were more likely to lead to possible resurgence, and nosocomial transmission was associated with the majority of outbreaks.
While spillover from wildlife has been a source for many Ebola disease outbreaks, multiple outbreaks may have originated from flare-ups of prior outbreak strains. Improving access to diagnostics as well as identifying groups at risk for resurgence of ebolaviruses will be crucial to preventing future outbreaks.
埃博拉疾病暴发的起源仍然是个谜。历史上的暴发事件被归因于野生动物的溢出。然而，最近的数据表明，一些暴发可能源自先前暴发株的人与人之间传播，而不是溢出。澄清埃博拉疾病暴发的起源可以提高对未来暴发的检测和缓解能力。
我们回顾了 1976 年至 2022 年所有埃博拉疾病暴发的起源，以分析每个暴发的最早病例和特征。暴发株的流行病学和系统发育关系用于进一步确定每个暴发的可能来源。
从 1976 年至 2022 年，有 35 次埃博拉疾病暴发，有 48 例原发性/索引病例。虽然大多数暴发与野生动物溢出有关，但人与人之间传播的死灰复燃可能导致约四分之一的埃博拉病毒引起的暴发。较大的暴发更有可能导致可能的死灰复燃，医院内传播与大多数暴发有关。
虽然野生动物溢出是许多埃博拉疾病暴发的来源，但多次暴发可能源自先前暴发株的爆发。改善诊断的获取以及识别埃博拉病毒死灰复燃的风险群体对于预防未来的暴发至关重要。
