Dynamics of simultaneous propagation of two COVID-19 strains

In this work, we present a mathematical framework that captures the dynamic behavior of the simultaneous propagation of two strains of COVID-19. We apply the next-generation matrix method to compute the basic reproduction ratio $\mathscr{R}_{0}$ . We investigate the stability of the model at each of the feasible equilibria. To validate our theoretical results, we have conducted numerical simulations. It is observed that if $\mathscr{R}_{0} \leq 1$ , eventually there will be no disease. However, if $\mathscr{R}_{0} > 1$ , a competition between the two COVID-19 strains will occur, and the more infectious variant will survive while the other disappears.