On the fractional-order mathematical model of COVID-19 with the effects of multiple non-pharmaceutical interventions

In this article, the Caputo fractional derivative operator of different orders $0<\alpha \le 1$ is applied to formulate the fractional-order model of the COVID-19 pandemic. The existence and boundedness of the solutions of the model are investigated by using the Gronwall-Bellman inequality. Further, the uniqueness of the model solutions is established by using the fixed-point theory. The Laplace Adomian decomposition method is used to obtain an approximate solution of the nonlinear system of fractional-order differential equations of the model with a different fractional-order $\alpha$ for every compartment in the model. Finally, graphical presentations are presented to show the effects of other fractional parameters $\alpha$ on the obtained approximate solutions.