Fig. 4.

The sample frequency of non-B.1.1.7 lineages in Greater London in community testing (n = 2957 sequenced samples). (A) Bar charts show the sample proportion of lineages with at least 20 samples after 31 March 2021. Error bars show 95% confidence intervals based on binomial sampling. (B) Stacked area charts show estimates over time of the frequency of lineages in the period 1 March to 29 May. Colour-code is identical to panel A). While a variety of non-B.1.1.7 variants (all S+) are in circulation in March and the beginning of April, by May B.1.617.2 predominates. A of this figure, displaying data that was available until mid-April, can be found in the Supplement (Supplementary Fig. 6).