https://www.gov.uk/government/groups/scientific-advisory-group-for-emergencies-sage-coronavirus-covid-19-response

From that site:
https://www.medrxiv.org/content/10.1101/2020.01.31.20019901v2.full.pdf+html

Referencing
"Capturing the time-varying drivers of an epidemic using stochastic dynamical systems."
https://academic.oup.com/biostatistics/article/14/3/541/259859

Looking as if the dispersive approach in [comment #11](https://forum.azimuthproject.org/discussion/comment/21938/#Comment_21938) is describing the current situation

![](https://imagizer.imageshack.com/img924/6510/SwnRIJ.png)

As these dispersive waves that hit a (perhaps temporary) herd immunity/quarantine ceiling aggregate, they create an envelope that continues to grow. So each of the subvolume curves shown in the figure above may represent a country, with a large country such as the USA with an initially slow growth adding a lagged response. The Maximum Entropy dispersion formulation of the logistic function sigmoid is simply a mechanism to provide variability to the mix, which thus emulates a global spread of growth.