Will Africa be spared the worst of COVID-19

COVID-19 appears to be extremely dangerous if you are old but not so risky if you are young.  Given the average age of most African nations, will we be spared the worst excesses of the pandemic that we see playing out in Europe and America?

There is an article in the latest issue of The Economist that suggests that the pattern exhibited by COVID-19 (that the young live while the old die) is not the norm for flu pandemics.  They go on to report on a theory why COVID-19 might be different.  Much of the damage caused by the virus is not down to the virus itself, but from an overreaction of the immune system to the virus.  The theory suggests that the inappropriate immune response might be caused from exposure to earlier flu infections that the youth were not exposed to.

There are also suggestions that a warmer climate might retard the spread of the virus or that BCG inoculations might somehow protect us from the disease severity.  

Let's continue to hope that this time the African poor will not be the ones hit hardest by a global disaster.  While we hope, we should continue to monitor the data!  Here we must be sensitive to changes in the age patterns of the reported deaths.  The warning flags should go up if more deaths (than the international experience suggests) are being reported in the age band 20 to 59.

The latest version of the NMG model was calibrated to 26 April 2020 and can be found at https://nmg-covid-19.sctechnology.co.za/ The model has been adapted in two ways to assist with monitoring the progression of COVID-19 in South Africa:

• The Infected Fatality Ratio parameter that is used to estimate the unreported lives infected by the virus is adjusted in the model for the age pattern of reported deaths.  This adjusts the model forecast for any increases in deaths (above that expected) in the 20 to 59 age band;
• The model allows the user to obtain projections for individual provinces as well as for South Africa as a whole.

An analysis of the reported deaths by province shows that the pattern cannot be explained by the different demographics alone.  Some other factors appear to be at play.  

Most lives over age 60 live in  Gauteng (1270 000) and KwaZulu Natal (930 000).

There are a similar number of lives over age 60 living in the Eastern Cape (760 000) and the Western Cape (690 000).  

The reported deaths are, however, highest for the Western Cape and KwaZulu Natal, and lowest for Gauteng.

If we move onto different lockdown severity levels in the different provinces, the experience across the provinces may become even more diverse.

29 April 2020