The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has cost over 2.2 million lives, among the more than 103 million cases. The only definitive control method is the production of herd immunity via vaccination, and the earliest vaccines to receive emergency use approval are now being rolled out. However, many public health authorities project a gap of more than one year before global vaccination can be achieved.
