Sars Cov-2 Variants – Meta – Analysis
TL;DR
COVID-19, a novel coronavirus first detected in Wuhan in December 2019, caused a global pandemic and prompted widespread public-health measures and vaccine development and stronger ACE2 binding that may help explain faster spread.
Abstract
Background of the Study: SARS-COV-2 refers to severe acute respiratory syndrome coronavirus 2. It belongs to family Coronaviridae, subfamily Coronavirinae and β genera. Coronaviruses are crown-shaped particles with spikes protruding from their surface. The SARS-CoV-2 genome is a 29.9 kb positive-sense single-stranded RNA molecule containing 14 ORFs encoding four structural and 16 non-structural ones. Proteins (nsp 1-16). Structural proteins include spike protein (S), envelope protein (E), membrane protein (M) and nucleoprotein (N). Non-structural proteins are involved in viral RNA replication and gene expression, forming an RNA synthesis complex in which nsp12 functions as an RNA-dependent RNA polymerase. Unlike other RNA viruses, coronaviruses have RNA proofreading machinery to correct genetic mutations due to nsp14 3′-5′ exonuclease activity. However, it has been estimated that SARS-CoV-2 undergoes 3 × 10–6 mutations per nucleotide per replication cycle Aims & Objective: The aim of this study is to review the spread of current variants of SARS-CoV-viruses. 1. To look at the disease profile of different variants of SARS CoV-2 Virus. 2. To look at the current variants of SARS CoV-2 Virus prevalent in different parts of the world. Methods: A Meta analysis method is used to study about corona virus and its variants. Data was collected from various publications in indexed journals, recent editions of textbooks, website of CDC, NCDC, WHO. Follow by Prisma, at first stage of the search, 280 articles were found, and after reviewing the titles of the articles, 120 duplicate and overlapping articles were deleted and 160 articles remained. In total, 60 articles were removed due to noncompliance with the criteria, the extract of 40 potentially related articles were reviewed, and 50 articles were excluded due to lack of access to the full text articles. Finally, 10 appropriate papers were selected to enter the meta-analysis stage. Results: SARS-CoV-2 spike mutations can increase transmissibility and immune escape, while some recurrent mutations may reduce disease severity. It also finds limited cross-protection across related coronaviruses, evidence of recombination in SARS-CoV, and stronger ACE2 binding that may help explain faster spread. SARS-CoV was detected in 329 of 436 patients, or 75%, and human metapneumovirus in 41 of 335 patients, or 12%; other respiratory pathogens were rare. The macaque experiment further showed all 4 infected macaques shed virus, and 3 of 4 developed lung damage similar to human SARS. Conclusion: COVID-19, a novel coronavirus first detected in Wuhan in December 2019, caused a global pandemic and prompted widespread public-health measures and vaccine development. The outbreak reduced active cases through vaccination but exposed major gaps in pandemic preparedness, prompting calls for stronger long-term readiness.