  This paper considers an explicit numerical scheme for solving the
mathematical model of the propagation of Covid-19 epidemic with undetected
infectious cases. We analyze the stability and convergence rate of the new
approach in $L^{\infty}$-norm. The proposed method is less time consuming.
Furthermore, the method is stable, at least second-order convergent and can
serve as a robust tool for the integration of general systems of ordinary
differential equations. A wide set of numerical evidences which consider the
case of Cameroon are presented and discussed.
