a, Daily case number and time-varying reproduction number (Rt) during the period of 1 March 2021 to 30 June 2021 (ref. 5). Plot shows reproduction numbers from Southeast Asia (SEA), Indonesia (the country with the highest case number) and Myanmar. On the basis of existing data from Myanmar, the reproduction number has already exceeded 1.0. b, Proportion of SARS-CoV-2 variants during the period of March 2021 to June 2021, presented as pie charts with colors according to Pango lineages (https://cov-lineages.org/index.html; database version 2021-06-15) and World Health Organization classification. Lines linking the pie charts indicate putative connections of viral populations (same Pango color code) between countries. The regional analysis was based on the sequencing data from COVID-19 Network Investigations and from other countries in Southeast Asia deposited at the GISAID database (https://www.epicov.org/epi3/; database version 2021-06-28) with genomes associated with Cambodia (300), Indonesia (831), Malaysia (486), Myanmar (10), Philippines (1,290), Singapore (769), Thailand (872) and Vietnam (86). Detailed data visualization is available in the Nextstrain format at https://coni.team/resource/. Publ. note: Springer Nature is neutral about jurisdictional claims in maps.