Are we seeing the start of a third wave?

An analysis of the reported COVID-19 infections by province shows an uptick in infections in a number of provinces, most notably Gauteng. This uptick is, however, not yet mirrored in the data on COVID-19 hospital admissions as reported to the National Institute for Communicable Diseases (NICD) as can be seen in the second graph below.


The hospital admission data taken from the NICD web site shows a level of COVID-19 activity in Gauteng but nothing that can be regarded as evidence of the start of a third wave. The evidence does show that the virus remains active in the population even when the speed of propagation is below the level required for a third wave.


The SEIR modelling logic tells us that the virus should die out in a population when the speed of propagation falls below a critical level.  According to this logic, viral activity is either increasing or reducing in a population but cannot maintain itself at the low levels as we are seeing in the South African population. This is yet another feature of this pandemic we need to better understand as it may well be our new normal.

11 May 2021




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