THE INITIAL AND DAILY COVID-19 EFFECTIVE REPRODUCTIVE NUMBER IN SOUTH AFRICA
This report summarises national laboratory testing for SARS-CoV-2, the virus causing COVID-19, in South Africa. This report is based on data collected up to 20 February 2021 (week 7 of 2021).
- From August 2020 through February 2021, estimates of R using three different data sources, daily numbers of laboratory-confirmed COVID-19 cases, hospital admissions, and deaths were generally similar.
- Nationally, during stage 2 lockdown, the daily R remained initially constant, then increased slightly, with an average value near 1 at the end of this period. During stage 1 lockdown, the daily R increased steadily until the second week of December, when it peaked and then decreased until the end of this period. The average R at the end of stage 1 lockdown was between 1 and 1.5. During the adjusted stage 3 lockdown, the daily R remained initially steady, then dropped sharply for the remainder of January.
- In the provincial level analysis trends were generally similar to the national picture except for differences in timing related to differences in the timing of the first and second COVID-19 waves.
The increase in R towards the end of stage one may have resulted from a combination of relaxation of implementation of controls to prevent the spread of COVID-19 at the end of the year as well as possible effects of the new lineage SARS-CoV-2 501Y.V2. Reductions in R during stage 3 could be as a result of increased measures to control COVID-19 as well as increasing population immunity.