We had a bad week

The number of confirmed cases and reported deaths over the last week has put South Africa back on the exponential growth curve for virus infections.  When re-calibrating the NMG model to fit the latest data, I needed to increase the transmission rate that caused the reproduction number implied by the model to increase from 1.28 to 2.00.  A reproduction number of 2.00 means that every one infectious person will infect two new people with the virus.  The re-calibrated model is available at https://nmg-covid-19.sctechnology.co.za/

 One week is a very short time period to be basing projections on, but then modelling this pandemic was never going to be easy.  If we wait for reliable data, the pandemic will have come and gone.  

 What I can say is that very few people that I have spoken to expected the lockdown to be effective in the poorer communities of South Africa.  We then need to be sensitive to data that confirms this so that Government does not persist with an intervention that is not working but that has many downsides.

 So we had a bad week!  What do we do now? Let's take another look at the worst-case deaths from COVID-19:
The worst-case scenario from the NMG model assuming no extension to the lockdown projects some 180900 deaths from COVID-19 in South Africa.  

 This is no doubt a scary number.

 What is less scary is the 5400 COVID-19 deaths expected in the 18 to 44 age group (if South Africa follows international patterns).




There are a number of commentators calling for Government to look beyond a generalised lockdown at other strategies for containing the pandemic.  One such commentator is Alex van den Heever, a professor at the Wits School of Governance.  You can access his paper at https://drive.google.com/AlexvdHeever

 I would like to suggest that our focus should be on how best to protect those most vulnerable to COVID-19.  This group, to my mind, is best protected by getting the economy back working and focusing our support efforts on the much smaller vulnerable group where resources and effort can be more effectively applied.
20 April 2020

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