A deterministic mathematical model for the transmission dynamics of COVID-19 is formulated, analysed and validated with real data.
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It is shown that model exhibit a backward bifurcation phenomenon if people recover without permanent immunity.
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Recent history of similar outbreaks plays an important role in delaying the outbreak at the initial stage provided the average effectiveness of self-protection measures is high enough.
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It is necessary to detect and isolate at least 30% of the asymptomatic cases and 50% of the symptomatic individuals if the disease is to be contained.
Abstract
In this article, a mathematical model for the transmission of COVID-19 disease is formulated and analysed. It is shown that the model exhibits a backward bifurcation at when recovered individuals do not develop a permanent immunity for the disease. In the absence of reinfection, it is proved that the model is without backward bifurcation and the disease free equilibrium is globally asymptotically stable for . By using available data, the model is validated and parameter values are estimated. The sensitivity of the value of to changes in any of the parameter values involved in its formula is analysed. Moreover, various mitigation strategies are investigated using the proposed model and it is observed that the asymptomatic infectious group of individuals may play the major role in the re-emergence of the disease in the future. Therefore, it is recommended that in the absence of vaccination, countries need to develop capacities to detect and isolate at least 30% of the asymptomatic infectious group of individuals while treating in isolation at least 50% of symptomatic patients to control the disease.