Ebola virus disease (EVD) is a rare but fatal disease of humans and other primates caused by Ebola viruses. Study shows that the 2014-2015 EVD outbreak causes more than 10,000 deaths. In this paper, we propose and analyze a deterministic model to study the transmission dynamics of EVD in Sierra Leone, Guinea, and Liberia. Our analyses show that the model has two equilibria: (1) the disease-free equilibrium (DFE) which is locally asymptotically stable when the basic reproduction number ([Formula: see text]) is less than unity and unstable if it is greater than one, and (2) an endemic equilibrium (EE) which is globally asymptotically stable when [Formula: see text] is greater than unity. Furthermore, the backward bifurcation occurs, a coexistence between a stale DFE and a stable EE even if the [Formula: see text] is less than unity, which makes the disease control more strenuous and would depend on the initial size of subpopulation. By fitting to reported Ebola cases from Sierra Leone, Guinea, and Liberia in 2014-2015, our model has captured the epidemic patterns in all three countries and shed light on future Ebola control and prevention strategies.

中文翻译：

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对 2014-2015 年塞拉利昂、几内亚和利比里亚埃博拉病毒病爆发的高危和低危易感个体的影响进行建模

埃博拉病毒病 (EVD) 是一种由埃博拉病毒引起的人类和其他灵长类动物罕见但致命的疾病。研究表明，2014-2015 年埃博拉病毒病爆发导致 10,000 多人死亡。在本文中，我们提出并分析了一个确定性模型来研究塞拉利昂、几内亚和利比里亚的埃博拉病毒病传播动态。我们的分析表明该模型有两个平衡：（1）无病平衡（DFE），当基本再生数（[公式：见正文]）小于统一时局部渐近稳定，如果大于一，以及 (2) 当 [公式：见正文] 大于 1 时全局渐近稳定的地方性均衡 (EE)。此外，即使[公式：见正文]小于统一，也会发生后向分叉，陈旧的 DFE 和稳定的 EE 共存，这使得疾病控制更加费力，并且将取决于亚群的初始规模。通过拟合塞拉利昂、几内亚和利比里亚 2014-2015 年报告的埃博拉病例，我们的模型捕捉到了这三个国家的流行模式，并阐明了未来的埃博拉控制和预防策略。