A very simple model to account for the rapid rise of the British variant of SARS-CoV-2 in several countries and the world

Since its first detection in the UK in September 2020, a highly contagious version of the coronavirus, called the British variant or B.1.1.7 SARS-CoV-2 virus lineage, is rapidly spreading across several countries and becoming the dominant strain in the outbreak.

Here it is shown that a very simple evolutionary model, when including the latest available data from March 2021, can fit the observed change in frequency of B.1.1.7 for several countries, regions of countries and the whole world with a single parameter which is almost universal.