Epidemiological Update: Variants of SARS-CoV-2 in the Americas (24 March 2021)

ABSTRACT

At the global level, a constant change is observed in the proportion of predominant clades since the start of the pandemic to date. As of 5 July 2020, 49% of the samples available through GISAID were associated with the GR clade and by 22 August 2020 it had increased to 53%, whereas by 7 November 2020 the proportion had decreased to 37% and by 22 March 2021 it decreased further to 18% of the proportion of samples. In contrast, there has been a relatively stable trend in proportion of the GH clade, contributing 35% to the total of samples available in GISAID sequenced as of 6 December 2020 and 30% as of 22 March 2021. Regarding the GRY clade, there has been an increase in proportion from 5% as of 6 December 2020 to 39% as of 22 March 2021.