COVID-19: A review of newly formed viral clades, pathophysiology, therapeutic strategies and current vaccination tasks

Abstract

Today, the world population is facing an existential threat by an invisible enemy known as severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) or COVID-19. It is highly contagious and has infected a larger fraction of human population across the globe on various routes of transmission. The detailed knowledge of the SARS-CoV-2 structure and clinical aspects offers an important insight into the evolution of infection, disease progression and helps in executing the different therapies effectively. Herein, we have discussed in detail about the genome structure of SARS-CoV-2 and its role in the proteomic rational spread of different muted species and pathogenesis in infecting the host cells. The mechanisms behind the viral outbreak and its immune response, the availability of existing diagnostics techniques, the treatment efficacy of repurposed drugs and the emerging vaccine trials for the SARS-CoV-2 outbreak also have been highlighted. Furthermore, the possible antiviral effects of various herbal products and their extracted molecules in inhibiting SARS-CoV-2 replication and cellular entry are also reported. Finally, we conclude our opinion on current challenges involved in the drug development, bulk production of drug/vaccines and their storage requirements, logistical procedures and limitations related to dosage trials for larger population.

SARS-CoV-2: Recent Variants and Clinical Efficacy of Antibody-Based Therapy

“…Interferon’s approach to storming our bodies, enthused researchers to see whether an improvement in interferon might help in the early-stage infection of patients with SARS-CoV-2 ( Della-Torre et al., 2020 ). Preliminary investigations in cells and mice have yielded reassuring results that have led to clinical trials ( Murugan et al., 2021 ). On October 20, 2021, Synairgen proclaimed that the drug was moving forward into a Phase III clinical trial in mild- to -moderate SARS-CoV-2 patients.…”

Chitosan and its derivatives as polymeric anti-viral therapeutics and potential anti-SARS-CoV-2 nanomedicine

“…The COVID-19 pandemic is marked by a widespread Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. Infected individuals may develop serious medical complications such as acute respiratory distress syndrome or even face death, especially patients with cancer, immunosuppression or comorbidities who may experience increased risks of cardiovascular disorders, thromboembolic stroke, Guillain-Barre syndrome, rhabdomyolysis, brain, hepatic and acute kidney injury ( Bourgonje et al, 2020 ; Murugan et al, 2021 ; Sanyaolu et al, 2020 ). With lockdown and safety measures for the prevention of virus spread ( Donthu & Gustafsson, 2020 ), the summative incidences of SARS-CoV-2 infection have a great impact on lives and livelihoods, which warrants the advancement of anti-SARS-CoV-2 therapeutics.…”

“…SARS-CoV-2 is a spherical virus classified under the order of Nidovirales , which has a diameter of 100 nm (60–140 nm) and a mass of 1000 MDa ( Bar-On, Flamholz, Phillips, & Milo, 2020 ; Hu, Frieman, & Wolfram, 2020 ; Murugan et al, 2021 ). Its transmembrane spike glycoprotein (S protein) presents 10 nm-long trimers.…”

“…Chloroquine phosphate also stimulates the host immune system to defend against viral infection by inhibiting pro-inflammatory cytokine activity and synthesis, or by inducing anti-SARS-CoV-2 cytotoxic T lymphocytes ( Devaux et al, 2020 ). Many phytochemicals and natural products, such as luteolin, myricetin, quercetin and kaempferol, have been shown to exhibit a broad-spectrum anti-viral activity and suppress the hyperinflammatory response linked to SARS-CoV-2 infection ( McKee et al, 2020 ; Murugan et al, 2021 ). However, their mechanism of action is not fully understood ( McKee et al, 2020 ).…”

Insights into the structure and dynamics of SARS-CoV-2 spike glycoprotein double mutant L452R-E484Q

“…The SARS-CoV-2 genome is the largest among all RNA-viruses, packed with a helical capsid, formed by a nucleocapsid protein and RNA surrounded by an envelope. There are three structural proteins, namely membrane protein (M), an envelope protein (E), and the spike protein (S), associated with the envelope that is mainly involved in replication, assembly and cell fusion (Murugan et al 2021;Arya et al 2021). The S protein facilitates the entry of the virus into the host cells with the help of the angiotensin-converting enzyme 2 (ACE2) receptor (Fig.…”