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During the COVID-19 pandemic, one of the biggest challenges was the continuous evolution of SARS-CoV-2 through various mutations. This has resulted in the emergence of several variants and subvariants. The escape mutations are reported as significant mutations in several variants and subvariants responsible for immune, antibody, and nAb escape. It has been reported that FLip mutations (L455F and F456L) in the spike RBD are responsible for immune evasion and antibody escape. Recently, WHO has included a new SARS-CoV-2 VOI, JN.1 lineage, a descendent of BA.2.86. The variant is reported from more than 41 countries, including France, the USA, Canada, the UK, Singapore, Sweden, and India. It contains FLip mutations in the spike protein in RBD (L455F and F456L). The risk assessment of the variant by WHO shows it has increased transmission, immune escape, and antibody escape due to the mutations. The article illustrated that FLip mutations in RBD (L455F and F456L) are responsible for augmented transmission and immune and antibody escape. [ABSTRACT FROM AUTHOR]

Several clinical trials started during the COVID-19 pandemic to discover effective therapeutics led to identify a few candidates from the major clinical trials. However, in the past several months, quite a few SARS-CoV-2 variants have emerged with significant mutations. Major mutations in the S-glycoprotein and other parts of the genome have led to the antibody's escape to small molecule-based therapeutic resistance. The mutations in S-glycoprotein trigger the antibody escape/resistance, and mutations in RdRp might cause remdesivir resistance. The article illustrates emerging mutations that have resulted in antibody escape to therapeutics resistance. In this direction, the article illustrates presently developed neutralizing antibodies (with their preclinical, clinical stages) and antibody escapes and associated mutations. Finally, owing to the RdRp mutations, the antiviral small molecules resistance is illustrated. [ABSTRACT FROM AUTHOR]

Recently, India is at risk due to the exponential rising of COVID-19 infection, which generated a second wave. This infection rise may affect the vaccination program in India, and it can also affect vaccine production. In this manuscript, we have discussed the psychosocial and political factors that have driven the current wave of India. We have also tried to depict the psychosocial and political obstacles that are impairing the vaccination program. [ABSTRACT FROM AUTHOR]

The COVID-19 outbreak is a disaster now throughout the world. To stop this outbreak, we appeal through the paper for extensive partnership, collaboration and teamwork among the all levels of workers such as scientist, doctors, medical professionals, social workers, policy makers, governments, pharmaceutical firms, funding aid agencies to stop the pandemic immediately. [ABSTRACT FROM AUTHOR]

The massive increase in COVID-19 infection had generated a second wave in India during May–June 2021 with a critical pandemic situation. The Delta variant (B.1.617.2) was a significant factor during the second wave. Conversely, the UK had passed through the crucial phase of the pandemic from November to December 2020 due to B.1.1.7. The study tried to comprehend the pandemic response in the UK and India to the spread of the B.1.1.7 (Alpha, UK) variant and B.1.617.2 (Delta, India) variant. This study was performed in three directions to understand the pandemic response of the two emerging variants. First, we served comparative genomics, such as genome sequence submission patterns, mutational landscapes, and structural landscapes of significant mutations (N501Y, D614G, L452R, E484Q, and P681R). Second, we performed evolutionary epidemiology using molecular phylogenetics, scatter plots of the cluster evaluation, country-wise transmission pattern, and frequency pattern. Third, the receptor binding pattern was analyzed using the Wuhan reference strain and the other two variants. The study analyzed the country-wise and region-wise genome sequences and their submission pattern, molecular phylogenetics, scatter plot of the cluster evaluation, country-wise geographical distribution and transmission pattern, frequency pattern, entropy diversity, and mutational landscape of the two variants. The structural pattern was analyzed in the N501Y, D614G L452R, E484Q, and P681R mutations. The study found increased molecular interactivity between hACE2-RBD binding of B.1.1.7 and B.1.617.2 compared to the Wuhan reference strain. Our receptor binding analysis showed a similar indication pattern for hACE2-RBD of these two variants. However, B.1.617.2 offers slightly better stability in the hACE2-RBD binding pattern through MD simulation than B.1.1.7. The increased hACE2-RBD binding pattern of B.1.1.7 and B.1.617.2 might help to increase the infectivity compared to the Wuhan reference strain. [Display omitted] • Comparative genomics of two emerging SARS-CoV-2 variants (B.1.1.7 and B. 1.617.2). • Evolutionary epidemiology, geographical distribution and country-wise transmission patterns of study of Alpha.1.1.7 and Delta. 1.617.2. • Landscape of significant mutations such as L452R, E484Q, N501Y, D614G and P681R. • RBD-hACE2 receptor binding pattern analysis in B.1.1.7 and B. 1.617.2 compare to Wuhan reference strain. [ABSTRACT FROM AUTHOR]

In the last two years, the world encountered the SARS-CoV-2 virus, which is still dominating the population due to the absence of a viable treatment. To eradicate the global pandemic, scientists, doctors, and researchers took an exceptionally significant initiative towards the development of effective therapeutics to save many lifes. This review discusses about the single-domain antibodies (sdAbs), also called nanobodies, their structure, and their types against the infections of dreadful SARS-CoV-2 virus. A precise description highlights the nanobodies and their therapeutic application against the other selected viruses. It aims to focus on the extraordinary features of these antibodies compared to the conventional therapeutics like mAbs, convalescent plasma therapy, and vaccines. The stable structure of these nanobodies along with the suitable mechanism of action also confers greater resistance to the evolving variants with numerous mutations. The nanobodies developed against SARS-CoV-2 and its mutant variants have shown the greater neutralization potential than the primitive ones. Engineering of these specialized antibodies by modern biotechnological approaches will surely be more beneficial in treating this COVID-19 pandemic along with certain other viral infections. [ABSTRACT FROM AUTHOR]

The progression of the COVID-19 pandemic has generated numerous emerging variants of SARS-CoV-2 on a global scale. These variants have gained evolutionary advantages, comprising high virulence and serious infectivity due to multiple spike glycoprotein mutations. As a reason, variants are demonstrating significant abilities to escape the immune responses of the host. The D614G mutation in the S-glycoprotein of SARS-CoV-2 variants has shown the most efficient interaction with the ACE2 receptor of the cells. This explicit mutation at amino acid position 614 (aspartic acid-to-glycine substitution) is the prime cause of infection and re-infection. It changes the conformation of RBD and cleavage patterns S-glycoprotein with higher stability, replication fitness, and fusion efficiencies. Therefore, this review aims to provide several crucial pieces of information associated with the D614 mutational occurrence of SARS-CoV-2 variants and their infectivity patterns. This review will also effectively emphasize the mechanism of action of D614G mutant variants, immune escape, and partial vaccine escape of this virus. Furthermore, the viral characteristic changes leading to the current global pandemic condition have been highlighted. Here, we have tried to illustrate a novel direction for future researchers to develop effective therapeutic approaches and counterweight strategies to minimize the spread of COVID-19. Key points • D614G mutation arises within the S-glycoprotein of significant SARS-CoV-2 variants. • The D614G mutation affects infection, re-infection, cleavage patterns of S-glycoprotein, and replication fitness of SARS-CoV-2 variants. • The D614G mutation influences the immunity and partial vaccine escape. [ABSTRACT FROM AUTHOR]

Presently, we need more therapeutic molecules for this COVID-19 outbreak. The severity and mortality of the disease is associated with a high level of release of cytokine in the patients which is known as CRS (cytokine release syndrome) or cytokine storm syndrome. IL-6 is a type of pro-inflammatory cytokine which release in the severe COVID-19 patients. This cytokine initiates CRS the JAK-STAT or MAPK/NF-κB-IL-6 pathway. Tocilizumab, a humanized monoclonal antibody, is designed to bind both mIL-6R (membrane bound receptor for IL-6) and sIL-6R (soluble receptor for IL-6) and inhibit the JAK-STAT or MAPK/NF-κB-IL-6 signaling pathway. It finally stops the cytokine storm syndrome. However, we need to understand that how tocilizumab is bound with mIL-6R or sIL-6R. Similarly, we also need to understand more about the real molecular mechanism of activity of tocilizumab. [ABSTRACT FROM AUTHOR]