Global emerging Omicron variant of SARS-CoV-2: Impacts, challenges and strategies.

Newly emerging variants of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are continuously posing high global public health concerns and panic resulting in waves of coronavirus disease 2019 (COVID-19) pandemic. Depending on the extent of genomic variations, mutations and adaptation, few of the variants gain the ability to spread quickly across many countries, acquire higher virulency and ability to cause severe disease, morbidity and mortality. These variants have been implicated in lessening the efficacy of the current COVID-19 vaccines and immunotherapies resulting in break-through viral infections in vaccinated individuals and recovered patients. Altogether, these could hinder the protective herd immunity to be achieved through the ongoing progressive COVID-19 vaccination. Currently, the only variant of interest of SARS-CoV-2 is Omicron that was first identified in South Africa. In this review, we present the overview on the emerging SARS-CoV-2 variants with a special focus on the Omicron variant, its lineages and hybrid variants. We discuss the hypotheses of the origin, genetic change and underlying molecular mechanism behind higher transmissibility and immune escape of Omicron variant. Major concerns related to Omicron including the efficacy of the current available immunotherapeutics and vaccines, transmissibility, disease severity, and mortality are discussed. In the last part, challenges and strategies to counter Omicron variant, its lineages and hybrid variants amid the ongoing COVID-19 pandemic are presented.

The role of disinfectants and sanitizers during COVID-19 pandemic: advantages and deleterious effects on humans and the environment.

Disinfectants and sanitizers are essential preventive agents against the coronavirus disease 2019 (COVID-19) pandemic; however, the pandemic crisis was marred by undue hype, which led to the indiscriminate use of disinfectants and sanitizers. Despite demonstrating a beneficial role in the control and prevention of COVID-19, there are crucial concerns regarding the large-scale use of disinfectants and sanitizers, including the side effects on human and animal health along with harmful impacts exerted on the environment and ecological balance. This article discusses the roles of disinfectants and sanitizers in the control and prevention of the current pandemic and highlights updated disinfection techniques against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This article provides evidence of the deleterious effects of disinfectants and sanitizers exerted on humans, animals, and the environment as well as suggests mitigation strategies to reduce these effects. Additionally, potential technologies and approaches for the reduction of these effects and the development of safe, affordable, and effective disinfectants are discussed, particularly, eco-friendly technologies using nanotechnology and nanomedicine.

SARS-CoV-2 infection during pregnancy and pregnancy-related conditions: Concerns, challenges, management and mitigation strategies-a narrative review.

The ongoing coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is a global public health problem. The SARS-CoV-2 triggers hyper-activation of inflammatory and immune responses resulting in cytokine storm and increased inflammatory responses on several organs like lungs, kidneys, intestine, and placenta. Although SARS-CoV-2 affects individuals of all age groups and physiological statuses, immune-compromised individuals such as pregnant women are considered as a highly vulnerable group. This review aims to raise the concerns of high risk of infection, morbidity and mortality of COVID-19 in pregnant women and provides critical reviews of pathophysiology and pathobiology of how SARS-CoV-2 infection potentially increases the severity and fatality during pregnancy. This article also provides a discussion of current evidence on vertical transmission of SARS-CoV-2 during pregnancy and breastfeeding. Lastly, guidelines on management, treatment, preventive, and mitigation strategies of SARS-CoV-2 infection during pregnancy and pregnancy-related conditions such as delivery and breastfeeding are discussed.

MERS-CoV: epidemiology, molecular dynamics, therapeutics, and future challenges.

The Severe Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has gained research attention worldwide, given the current pandemic. Nevertheless, a previous zoonotic and highly pathogenic coronavirus, the Middle East Respiratory Syndrome coronavirus (MERS-CoV), is still causing concern, especially in Saudi Arabia and neighbour countries. The MERS-CoV has been reported from respiratory samples in more than 27 countries, and around 2500 cases have been reported with an approximate fatality rate of 35%. After its emergence in 2012 intermittent, sporadic cases, nosocomial infections and many community clusters of MERS continued to occur in many countries. Human-to-human transmission resulted in the large outbreaks in Saudi Arabia. The inherent genetic variability among various clads of the MERS-CoV might have probably paved the events of cross-species transmission along with changes in the inter-species and intra-species tropism. The current review is drafted using an extensive review of literature on various databases, selecting of publications irrespective of favouring or opposing, assessing the merit of study, the abstraction of data and analysing data. The genome of MERS-CoV contains around thirty thousand nucleotides having seven predicted open reading frames. Spike (S), envelope (E), membrane (M), and nucleocapsid (N) proteins are the four main structural proteins. The surface located spike protein (S) of betacoronaviruses has been established to be one of the significant factors in their zoonotic transmission through virus-receptor recognition mediation and subsequent initiation of viral infection. Three regions in Saudi Arabia (KSA), Eastern Province, Riyadh and Makkah were affected severely. The epidemic progression had been the highest in 2014 in Makkah and Riyadh and Eastern Province in 2013. With a lurking epidemic scare, there is a crucial need for effective therapeutic and immunological remedies constructed on sound molecular investigations.

SARS-CoV-2 existence in sewage and wastewater: A global public health concern?

The SARS-CoV-2/COVID-19 pandemic has spread across the globe and affected millions of individuals as of the efficient virus transmission potential mediated via multiple virus shedding routes. The presence of SARS-CoV-2 in the stool samples and its prolonged shedding in environmental compartments like sewage and wastewater signifies a potential threat adding to the transmission cycle of this novel virus. The potential role played by the asymptomatic COVID-19 patients in transmitting the disease via the fecal-oral route is now under investigation. Hence, in the present scenario, wastewater-based epidemiology, and sewage surveillance may provide valuable insights into the prevalence of SARS-CoV-2 among the human population and could serve as a sensitive surveillance system and a crucial early warning tool. Further studies are required to determine the survival of SARS-CoV-2 in the environment, transmissibility through wastewater, and the potential to infect humans via the fecal-oral route. Appropriate frameworks with regards to evaluation and analysis of SARS-CoV-2 will help implement appropriate intervention strategies and necessary sanitation practices to ensure virus free clean water supply to have a check on the further spread of this pandemic virus.

CRISPR-Cas System: An Approach With Potentials for COVID-19 Diagnosis and Therapeutics.

COVID-19, the human coronavirus disease caused by SARS-CoV-2, was reported for the first time in Wuhan, China in late 2019. COVID-19 has no preventive vaccine or proven standard pharmacological treatment, and consequently, the outbreak swiftly became a pandemic affecting more than 215 countries around the world. For the diagnosis of COVID-19, the only reliable diagnostics is a qPCR assay. Among other diagnostic tools, the CRISPR-Cas system is being investigated for rapid and specific diagnosis of COVID-19. The CRISPR-Cas-based methods diagnose the SARS-CoV-2 infections within an hour. Apart from its diagnostic ability, CRISPR-Cas system is also being assessed for antiviral therapy development; however, till date, no CRISPR-based therapy has been approved for human use. The Prophylactic Antiviral CRISPR in huMAN cells (PAC-MAN), which is Cas 13 based strategy, has been developed against coronavirus. Although this strategy has the potential to be developed as a therapeutic modality, it may face significant challenges for approval in human clinical trials. This review is focused on describing potential use and challenges of CRISPR-Cas based approaches for the development of rapid and accurate diagnostic technique and/or a possible therapeutic alternative for combating COVID-19. The assessment of potential risks associated with use of CRISPR will be important for future clinical advancements.

Geriatric Population During the COVID-19 Pandemic: Problems, Considerations, Exigencies, and Beyond.

The coronavirus disease 2019 (COVID-19) pandemic wreaked havoc worldwide, with more than 20 million confirmed cases and nearly 0. 75 million deaths as of 10th August 2020. Various factors determine the severity and symptoms of this infection. Older age and underlying diseases are the challenges being faced in controlling and treating COVID-19. In 2019, 703 million of the global population was older than 65 years of age. The estimated mortality due to COVID-19 in people older than 76 years of age is reportedly 18%. Frequent infections in older people, higher disease severity, and increased mortality are major challenges in the implementation of appropriate preventive measures and future strategies to protect against this disease in geriatric population. Poor health status, weak immune function, lowered organ function, increased probability of multiple underlying diseases, and poor attention to personal health can increase the susceptibility to various diseases in the geriatric population. Concerning inadequate immunity, the decrease expression of receptors and exaggerated pathophysiologic responses can be debilitating. However, future studies will reveal the hidden facets in these aspects in this COVID-19 catastrophe. In this article, we reviewed the main concerns of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in the geriatric population, including the risk of acquiring severe COVID-19 resulting in mortality, variation in clinical manifestations, and other pandemic-related concerns. We also discussed the need for increasing attention toward the elderly, taking appropriate prevention and control measures, and considering geriatric-related adjustments in vaccine design and development.

SARS-CoV-2/COVID-19 and advances in developing potential therapeutics and vaccines to counter this emerging pandemic.

A novel coronavirus (SARS-CoV-2), causing an emerging coronavirus disease (COVID-19), first detected in Wuhan City, Hubei Province, China, which has taken a catastrophic turn with high toll rates in China and subsequently spreading across the globe. The rapid spread of this virus to more than 210 countries while affecting more than 25 million people and causing more than 843,000 human deaths, it has resulted in a pandemic situation in the world. The SARS-CoV-2 virus belongs to the genus Betacoronavirus, like MERS-CoV and SARS-CoV, all of which originated in bats. It is highly contagious, causing symptoms like fever, dyspnea, asthenia and pneumonia, thrombocytopenia, and the severely infected patients succumb to the disease. Coronaviruses (CoVs) among all known RNA viruses have the largest genomes ranging from 26 to 32 kb in length. Extensive research has been conducted to understand the molecular basis of the SARS-CoV-2 infection and evolution, develop effective therapeutics, antiviral drugs, and vaccines, and to design rapid and confirmatory viral diagnostics as well as adopt appropriate prevention and control strategies. To date, August 30, 2020, no effective, proven therapeutic antibodies or specific drugs, and vaccines have turned up. In this review article, we describe the underlying molecular organization and phylogenetic analysis of the coronaviruses, including the SARS-CoV-2, and recent advances in diagnosis and vaccine development in brief and focusing mainly on developing potential therapeutic options that can be explored to manage this pandemic virus infection, which would help in valid countering of COVID-19.

SARS-CoV-2 jumping the species barrier: Zoonotic lessons from SARS, MERS and recent advances to combat this pandemic virus.

Coronavirus Disease 2019 (COVID-19), caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome - Coronavirus-2) of the family Coronaviridae, appeared in China in December 2019. This disease was declared as posing Public Health International Emergency by World Health Organization on January 30, 2020, attained the status of a very high-risk category on February 29, and now having a pandemic status (March 11). COVID-19 has presently spread to more than 215 countries/territories while killing nearly 0.75 million humans out of cumulative confirmed infected asymptomatic or symptomatic cases accounting to almost 20.5 million as of August 12, 2020, within a short period of just a few months. Researchers worldwide are pacing with high efforts to counter the spread of this virus and to design effective vaccines and therapeutics/drugs. Few of the studies have shown the potential of the animal-human interface and zoonotic links in the origin of SARS-CoV-2. Exploring the possible zoonosis and revealing the factors responsible for its initial transmission from animals to humans will pave ways to design and implement effective preventive and control strategies to counter the COVID-19. The present review presents a comprehensive overview of COVID-19 and SARS-CoV-2, with emphasis on the role of animals and their jumping the cross-species barriers, experiences learned from SARS- and MERS-CoVs, zoonotic links, and spillover events, transmission to humans and rapid spread, and highlights the new advances in diagnosis, vaccine and therapies, preventive and control measures, one health concept along with recent research developments to counter this pandemic disease.

Coronavirus Disease Pandemic (COVID-19): Challenges and a Global Perspective.

The technology-driven world of the 21st century is currently confronted with a major threat to humankind, represented by the coronavirus disease (COVID-19) pandemic, caused by the severe acute respiratory syndrome, coronavirus-2 (SARS-CoV-2). As of now, COVID-19 has affected more than 6 million confirmed cases and took 0.39 million human lives. SARS-CoV-2 spreads much faster than its two ancestors, SARS-CoV and Middle East respiratory syndrome-CoV (MERS-CoV), but has low fatality rates. Our analyses speculate that the efficient replication and transmission of SARS-CoV-2 might be due to the high-density basic amino acid residues, preferably positioned in close proximity at both the furin-like cleavage sites (S1/S2 and S2') within the spike protein. Given the high genomic similarities of SARS-CoV-2 to bat SARS-like CoVs, it is likely that bats serve as a reservoir host for its progenitor. Women and children are less susceptible to SARS-CoV-2 infection, while the elderly and people with comorbidities are more prone to serious clinical outcomes, which may be associated with acute respiratory distress syndrome (ARDS) and cytokine storm. The cohesive approach amongst researchers across the globe has delivered high-end viral diagnostics. However, home-based point-of-care diagnostics are still under development, which may prove transformative in current COVID-19 pandemic containment. Similarly, vaccines and therapeutics against COVID-19 are currently in the pipeline for clinical trials. In this review, we discuss the noteworthy advancements, focusing on the etiological viral agent, comparative genomic analysis, population susceptibility, disease epidemiology and diagnosis, animal reservoirs, laboratory animal models, disease transmission, therapeutics, vaccine challenges, and disease mitigation measures.

An update on SARS-CoV-2/COVID-19 with particular reference to its clinical pathology, pathogenesis, immunopathology and mitigation strategies.

Coronavirus Disease 2019 (COVID-19), emerged in early December 2019 in China and became a pandemic situation worldwide by its rapid spread to more than 200 countries or territories. Bats are considered as the reservoir host, and the search of a probable intermediate host is still going on. The severe form of the infection is associated with death is mainly reported in older and immune-compromised patients with pre-existing disease history. Death in severe cases is attributed to respiratory failure associated with hyperinflammation. Cytokine storm syndrome associated with inflammation in response to SARS-CoV-2 infection is considered as the leading cause of mortality in COVID-19 patients. COVID-19 patients have thus higher levels of many proinflammatory cytokines and chemokines. The blood laboratory profile of the COVID-19 patients exhibits lymphopenia, leukopenia, thrombocytopenia, and RNAaemia, along with increased levels of aspartate aminotransferase. SARS-CoV-2 infection in pregnant women does not lead to fetus mortality, unlike other zoonotic coronaviruses such as SARS-CoV and MERS-CoV, and there is, to date, no evidence of intrauterine transmission to neonates. Rapid diagnostics have been developed, and significant efforts are being made to develop effective vaccines and therapeutics. In the absence of any virus-specific therapy, internationally, health care authorities are recommending the adoption of effective community mitigation measures to counter and contain this pandemic virus. This paper is an overview of this virus and the disease with a particular focus on SARS-CoV-2/COVID-19 clinical pathology, pathogenesis, and immunopathology, along with recent research developments.