The emergence of highly contagious Alpha, Beta, Gamma and Delta variants and strains of COVID-19 put healthy people on high risk of contracting the infection. In addition to the vaccination strategies, the nonpharmaceutical intervention use of face mask gives protection against the contraction of the virus. To understand the efficacy of such, we present a Caputo type fractional dynamical model to assess the efficacy of facemask to the community transmission of COVID-19. The existence and uniqueness of the solution was established, and subsequently, with the use of the generalized mean value theorem, the positivity and boundedness of the solutions were established. The disease free equilibrium (DFE) was found to be asymptotically stable when the basic reproduction number By constructing quadratic Lyapunov function, the equilibria (DFE and Endemic) were found to be globally asymptotically stable.
Keywords: COVID-19; Caputo; boundedness and stability; existence and uniqueness; positivity.