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Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant lineage replacement over the first 6 months of the pandemic. The proportion of variant lineages identified over half-month periods from the earliest available sequence to June 2020 is shown at (A) global and (B) continental levels. Jan, the complete genomes isolated on January 2020 and before. ‘1’ and ‘2’ represent the first and second half of the month, respectively.
