How the novel coronavirus has evolved by Reuters

As Covid-19 swept across the world, it mutated into several major groups, or strains, as it adapted to its human hosts. Mapping and understanding those changes to the virus is crucial to developing strategies to combat the COVID-19 disease it causes.

Reuters analysed over 185,000 genome samples from the Global Initiative on Sharing All influenza Data (GISAID), the largest database of novel coronavirus genome sequences in the world, to show how the global dominance of major strains has shifted over time.