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Since its emergence as a pneumonia-like outbreak in the Chinese city of Wuhan in late 2019, the novel coronavirus disease COVID-19 has spread widely to become a global pandemic. The first case of COVID-19 in India was reported on 30 January 2020 and since then it has affected more than ten million people and resulted in around 150,000 deaths in the country. Over time, the viral genome has accumulated mutations as it passes through its human hosts, a common evolutionary mechanism found in all microorganisms. This has implications for disease surveillance and management, vaccines and therapeutics, and the emergence of reinfections. Sequencing the viral genome can help monitor these changes and provides an extraordinary opportunity to understand the genetic epidemiology and evolution of the virus as well as tracking its spread in a population. Here we review the past year in the context of the phylogenetic analysis of variants isolated over the course of the pandemic in India and highlight the importance of continued sequencing-based surveillance in the country. [ABSTRACT FROM AUTHOR]

The present study aims to investigate the genomic variability and epidemiology of SARS-CoV-2 in Pakistan along with its role in the spread and severity of infection during the three waves of COVID-19. A total of 453 genomic sequences of Pakistani SARS-CoV-2 were retrieved from GISAID and subjected to MAFFT-based alignment and QC check which resulted in removal of 53 samples. The remaining 400 samples were subjected to Pangolin-based genomic lineage identification. And to infer our SARS-CoV-2 time-scaled and divergence phylogenetic trees, 3804 selected global reference sequences plus 400 Pakistani samples were used for the Nextstrain analysis with Wuhan/Hu-1/2019, as reference genome. Finally, maximum likelihood based phylogenetic tree was built by using the Nextstrain and coverage map was created by employing Nextclade. By using the amino acid substitutions, the maximum likelihood phylogenetic trees were developed for each wave, separately. Our results reveal the circulation of 29 lineages, belonging to following seven clades G, GH, GR, GRY, L, O, and S in the three waves. From first wave, 16 genomic lineages of SARS-CoV-2 were identified with B.1(24.7%), B.1.36(18.8%), and B.1.471(18.8%) as the most prevalent lineages respectively. The second wave data showed 18 lineages, 10 of which were overlapping with the first wave suggesting that those variants could not be contained during the first wave. In this wave, a new lineage, AE.4, was reported from Pakistan for the very first time in the world. However, B.1.36 (17.8%), B.1.36.31 (11.9%), B.1.1.7 (8.5%), and B.1.1.1 (5.9%) were the major lineages in second wave. Third wave data showed the presence of nine lineages with Alpha/B.1.1.7 (72.7%), Beta/B.1.351 (12.99%), and Delta/B.1.617.2 (10.39%) as the most predominant variants. It is suggested that these VOCs should be contained at the earliest in order to prevent any devastating outbreak of SARS-CoV-2 in the country. [ABSTRACT FROM AUTHOR]

Clades are monophyletic groups composed of a common ancestor and all its lineal descendants. As the propensity of virulence of a disease depends upon the type of clade the virus belongs to and it causes different fatality rates of disease in different countries, so the clade-wise analysis of SARS-CoV-2 isolates collected from different countries can illuminate the actual evolutionary relationships between them. In this study, 1566 SARS-CoV-2 genome sequences across ten Asian countries are collected, clustered, and characterized based on the clade they belong to. The isolates are compared to the Wuhan reference sequence" hCoV-19/Wuhan/WIV04/19″ to identify the mutations that occurred at different protein regions. Structural changes in amino acids due to mutations lead to functional instability of the proteins. Detailed clade-wise functional assessments are carried out to quantify the stability and vulnerability of the mutations occurring in SARS-CoV-2 genomes which can shade light on personalized prevention and treatment of the disease and encourage towards the invention of clade-specific vaccines. • SARS-CoV-2 Isolates of ten different countries of the Asian continent are analysed. • Seven clades G, GH, GR, L, S, O, and V are circulated over those ten countries. • It is found that Isolates of clade GR and clade GH have highest amount of SNPs. • Most of the deleterious mutations occurred in the isolates those belong to clade GH. [ABSTRACT FROM AUTHOR]