Fascinating study shows that removing homogeneity assumptions from population models, and replacing it with variations in virus susceptibility, returns data that better fits the actual impact of Covid19.
The results imply that most of the slowing and reversal of COVID-19 mortality is explained by the build-up of herd immunity.
The estimate of the herd immunity threshold depends on the value specified for the infection fatality ratio (IFR): a value of 0.3% for the IFR gives 15% for the average herd immunity threshold.
Now, compare this to the simplistic exponential models provided to governments across the world, and here in NZ.
https://www.medrxiv.org/conte…/10.1101/2020.09.26.20202267v1