Genomic epidemiology of early SARS-CoV-2 transmission dynamics in Bangladesh

Abstract Background Genomic epidemiology has helped reconstruct the global and regional movement of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, there is still a lack of understanding of SARS-CoV-2 spread in some of the world’s least developed countries (LDCs). Methods To begin to address this disparity, we studied the transmission dynamics of the virus in Bangladesh during the country’s first COVID-19 wave by analysing case reports and whole-genome sequences from all eight divisions of the country. Results We detected > 50 virus introductions to the country during the period, including during a period of national lockdown. Additionally, through discrete phylogeographic analyses, we identified that geographical distance and population -density and/or -size influenced virus spatial dispersal in Bangladesh. Conclusions Overall, this study expands our knowledge of SARS-CoV-2 genomic epidemiology in Bangladesh, shedding light on crucial transmission characteristics within the country, while also acknowledging resemblances and differences to patterns observed in other nations.