“…The above-listed works perform experiments under a wide range of scenarios in which a single parameter is varied. Other work investigate the vulnerability of variation among population subgroups and aim to find a decent balance between diversity and fairness measures [20] . However, the essential and conclusive epidemiological characteristics of the SARS-CoV-2 virus, vaccine efficacy, vaccine-induced, and natural immunity remains under study, and their variations coexist [21] .…”