  The COVID-19 pandemic had profoundly changed the way we lived and perceived
our lives. The successful delivery of vaccines together with relentless effort
from all stakeholders helped us to ``reclaim our normal way life''. In this
article, we propose a mathematical model that incorporates most features of
COVID-19 transmission dynamics to investigate the contribution of vaccines to
control the pandemic. The basic reproduction number of the model, denoted by
$\mathcal{R}_0$ is calculated. During imperfect vaccination and recovery does
not lead into permanent immunity, we have shown that the model could exhibit a
backward bifurcation when $\mathcal{R}_0<1$. With perfect vaccination and
recovery guarantees permanent immunity, the disease-free equilibrium is
globally asymptotically stable for $\mathcal{R}_0<1$ and unstable for
$\mathcal{R}_0>1$. Numerical experiments are also conducted to support the
theoretical analysis. The model is fitted into a real data from open sources
and the sensitivity analysis of the basic reproduction number with respect to
involved parameters is done to identify the most sensitive parameters for
control intervention. Finally, we conclude from the numerical experiments that
vaccines have significantly improved the recovery rate from COVID-19 infection
but do not offer complete protection protection.
