COVID-19 is an emerging and rapidly evolving pandemic around the world, which causes severe acute respiratory syndrome and results in substantial morbidity and mortality. To examine the transmission dynamics of COVID-19, we investigate the spread of this pandemic using Malaysia as a case study and scrutinise its interactions with some exogenous factors such as limited medical resources and false detection problems. To do this, we employ a simple epidemiological model and analyse this system using modelling and dynamical systems techniques. We discover some contrasting findings with respect to the observations of basic reproduction number: while it is observed that R₀ seems to provide a good description of transmission dynamics in simple outbreak scenarios, this quantity might mislead the assessment on the severity of pandemic when certain complexities such as limited medical resources and false detection problems are incorporated into the model. In particular, we observe the possibility of a COVID-19 outbreak through bistable behaviour, even when the basic reproduction number is less than unity. Based on these findings, we caution policy makers not to make their decisions solely based on the guidance of the basic reproduction number only, which clearly could cause trouble.

COVID-19是世界范围内正在兴起且发展迅速的大流行病，它引起严重的急性呼吸综合症，并导致大量的发病和死亡。为了检查COVID-19的传播动态，我们以马来西亚为例，调查了这种大流行的传播情况，并仔细研究了其与某些外在因素（例如有限的医疗资源和错误的检测问题）之间的相互作用。为此，我们采用一个简单的流行病学模型，并使用建模和动态系统技术对该系统进行分析。我们发现关于基本繁殖数的观察结果有一些相反的发现：观察到R ₀似乎可以很好地描述简单暴发情况下的传播动态，当将某些复杂性（例如有限的医疗资源和错误的检测问题）纳入模型时，此数量可能会误导对大流行的严重性的评估。特别是，我们观察到即使基本复制数小于1时，也可能通过双稳态行为爆发COVID-19。基于这些发现，我们提醒政策制定者不要仅根据基本繁殖数量的指导做出决定，这显然会造成麻烦。