Fitting of the COVID-19 vaccination data for South Africa.

Fitting of the model to the death data (top plot) and active data (bottom plot) with extrapolation into the period of the vaccination campaign in South Africa for a period of 2 years, March 2020—March 2022. The vertical dotted line indicates the start of the COVID-19 vaccination campaign around day 350 of the pandemic. Assuming that on day 350, the virus mutations stopped and the social measures were still in place and fully adhered to, then the dynamics of the active cases would follow the dotted blue line, which shows that the number of active cases would decrease with vaccination. Similarly, the number of deaths would be expected to decrease with vaccination as highlighted by the dotted grey line. However, due to new variants and changes in social and COVID-19 measures, the number of active and death cases continued to increase even with vaccination in place, as shown by the solid line.