Clinical Characteristics of the First 100 Patients of COVID-19 in Tobruk, Libya: A Brief Report From Low-Resource Settings.

OBJECTIVE: This study aims to report the clinical features of a cohort of patients with suspected coronavirus disease (COVID-19) from Tobruk, Libya, and reflect upon the diagnosis challenge in low-resource settings. METHODS: A descriptive report of the first 100 patients with suspected COVID-19 who have visited the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and COVID-19 screening clinic at the National Centre for Disease Control in Tobruk, Libya. RESULTS: The most common presenting symptoms were fever (90%), cough (89%), dyspnea (85%), sore throat (79%), fatigue (78%), headache (64%), loss of smell (52%), loss of taste (53%), loss of appetite (43%), nausea and vomiting (26%), diarrhea (22%), and rhinorrhea (16%); 51% of the patients had lymphocytopenia, whereas 13% had thrombocytopenia. Bilateral infiltrates were the most common radiologic finding on chest X-ray (76%), and COVID-19 IgM and/or IgG antibodies were detected in 80% of the patients, whereas only 37% of the patients were tested positive by the reverse transcriptase polymerase chain reaction (RT-PCR). CONCLUSIONS: The disease continued its spread across the region. Fever, cough, and dyspnea were the main symptoms; 21% of the patients did not have any chest X-ray abnormalities. Initial negative results for either antibody testing or RT-PCR-testing for COVID-19 do not rule out the infection.

Current insights and molecular docking studies of the drugs under clinical trial as rdrp inhibitors in COVID-19 treatment.

Study background & Objective: After the influenza pandemic (1918), COVID-19 was declared a Vth pandemic by the WHO in 2020. SARS-CoV-2 is an RNA-enveloped single-stranded virus. Based on the structure and life cycle, Protease (3CLpro), rdrp, ACE2, IL-6, and TMPRSS2 are the major targets for drug development against COVID-19. Pre-existing several drugs (FDA-approved) are used to inhibit the above targets in different diseases. In coronavirus treatment, these drugs are also in different clinical trial stages. Remdesivir (rdrp inhibitor) is the only FDA-approved medicine for coronavirus treatment. In the present study, by using the drug repurposing strategy, 70 preexisting clinical or under clinical trial molecules were used in scrutiny for rdrp inhibitor potent molecules in coronavirus treatment being surveyed via docking studies. Molecular simulation studies further confirmed the binding mechanism and stability of the most potent compounds. MATERIAL AND METHODS: Docking studies were performed using the Maestro 12.9 module of Schrodinger software over 70 molecules with rdrp as the target and remdesivir as the standard drug and further confirmed by simulation studies. RESULTS: The docking studies showed that many HIV protease inhibitors demonstrated remarkable binding interactions with the target rdrp. Protease inhibitors such as lopinavir and ritonavir are effective. Along with these, AT-527, ledipasvir, bicalutamide, and cobicistat showed improved docking scores. RMSD and RMSF were further analyzed for potent ledipasvir and ritonavir by simulation studies and were identified as potential candidates for corona disease. CONCLUSION: The drug repurposing approach provides a new avenue in COVID-19 treatment.

Emergence and Re-emergence of Human Coronaviruses: Spike Protein as the Potential Molecular Switch and Pharmaceutical Target.

BACKGROUND: Recent emergence of COVID-19 caused by a new human coronavirus (CoV) strain (SARS-CoV-2), which originated from China, poses the future emergence of additional CoVs. In most of the cases of emergence of human CoVs, bats, palm civets, raccoon dogs and camels have been identified as the sources of human infections and as reservoir hosts. A review of comparative genomic and phenotypic characteristics of human CoV strains vis-à-vis their comparison with the corresponding animal isolates shall provide clues regarding the potential genomic, phenotypic and molecular factors responsible for host-switching, which may lead to prospective emergence and re-emergence of human CoV outbreaks in the future. METHODS: The seven known human strains of CoV were analyzed for the host and viral factors responsible for human outbreaks. The molecular factors responsible for host-susceptibility, virulence and pathogenesis were reviewed to predict the emergence and re-emergence of additional human CoV strains. CoV spike protein was evaluated as a potential viral receptor for host switching and the target for pharmaceutical design. RESULTS: A review of the factors associated with host-susceptibility, virulence and pathogenesis of seven known human CoV strains presents significant possibilities for the emergence of new CoV strain(s), leading to more human outbreaks. Continuous exposure of animals' handlers to the infected animals, environmental changes, improper sanitations, non-disposal of the solid waste and resumption of exotic animals markets provides favorable conditions for "host switching" and the emergence of new and potentially more virulent human CoV strains. Mutations in target genes (like spike protein), which facilitate the viral entry into the host-cells, provide a potential "molecular switch" for preferences of new host-receptors, genetic diversity, genetic-recombination and high virulence. Additionally, the clinical and environmental factors, asymptomatic carriers, the paucity of efficacious vaccines & therapeutics, inefficient disease management and infection control measures, lack of public awareness, and effective communication of information about more virulent human-adapted virus isolates are critical for the emergence of new and virulent SARS-CoV strains with high mortality and varied incubation period in the near future. Small molecules binding with conserved druggable regions of the CoV spike proteins may be effective against multiple strains of CoVs. CONCLUSION: High propensity of mutations and "molecular adaptations" in coronaviruses creates the hot spots and high potential for "host switching", leading to the emergence of more virulent strains of human CoVs. The public/global health agencies, medical communities and research scientists should be prepared for the emergence and re-emergence of new human CoV strain(s) leading to potential disease outbreaks. The inhibitors binding with conserved druggable regions of spike proteins from multiple strains CoV may have utility as broad-spectrum antiviral drugs to combat future emergence of CoVs.

Natural Products Homoharringtonine and Emetine Alkaloids as SARS-CoV-2 Treatment Options.

BACKGROUND: Viruses are known as the major causative agents for infectious diseases globally. The coronaviruses are one of the serious pathogens to cause serious diseases in humans. Recently identified SARSCoV- 2 from Wuhan City, China, has emerged as a serious threat to human health and caused a global pandemic. Bats have been confirmed as a primary source of infection. The vaccination of the human population and animals serving as a potential reservoir is a straightforward strategy to control the transmission of any pathogen to humans. Natural products from many herbal plants are well known to have novel antiviral properties and evaluated against various viral diseases. There are many alkaloids that have shown to be effective against coronaviruses. METHODS: Recently, the antiviral efficacy of natural alkaloids known as Homoharringtonine (HTT) and Emetine has been evaluated and provided promising results against coronaviruses, including SARS-CoVs. These alkaloids may be very useful and can be used as antivirals against SARS-CoV-2 because they have already been reported to inhibit the replication of SASRS-CoV and other viruses in cell lines. CONCLUSION: This review specifically focuses on the recent findings of these alkaloids against coronaviruses and possible treatment options for SARS-CoV-2. It is expected that natural products as alkaloids from herbal plants could be considered as novel and valuable candidates for the new antiviral drugs against SARS-CoV-2.

Current Overviews on COVID-19 Management Strategies.

The coronavirus pandemic hit the world lately and caused acute respiratory syndrome in humans. The causative agent of the disease was soon identified by scientists as SARS-CoV-2 and later called a novel coronavirus by the general public. Due to the severity and rapid spread of the disease, WHO classifies the COVID-19 pandemic as the 6th public health emergency even after taking efforts like worldwide quarantine and restrictions. Since only symptomatic treatment is available, the best way to control the spread of the virus is by taking preventive measures. Various types of antigen/antibody detection kits and diagnostic methods are available for the diagnosis of COVID-19 patients. In recent years, various phytochemicals and repurposing drugs showing a broad range of anti-viral activities with different modes of actions have been identified. Repurposing drugs such as arbidol, hydroxychloroquine, chloroquine, lopinavir, favipiravir, remdesivir, hexamethylene amiloride, dexamethasone, tocilizumab, interferon-ß, and neutralizing antibodies exhibit in vitro anti-coronaviral properties by inhibiting multiple processes in the virus life cycle. Various research groups are involved in drug trials and vaccine development. Plant-based antiviral compounds such as baicalin, calanolides, curcumin, oxymatrine, matrine, and resveratrol exhibit different modes of action against a wide range of positive/negative sense-RNA/DNA virus, and future researches need to be conducted to ascertain their role and use in managing SARS-CoV-2. Thus this article is an attempt to review the current understanding of COVID- 19 acute respiratory disease and summarize its clinical features with their prospective control and various aspects of the therapeutic approach.

Comparative Study of Gene Expression Profiling Unravels Functions Associated with Pathogenesis of Dengue Infection.

BACKGROUND: Dengue virus is a potential source of propagating dengue hemorrhagic fever. This virus leads to dengue hemorrhagic fever/dengue shock syndrome, benign syndrome, and severe syndrome and due to its infection, there occurs alterations at multiple levels such as gene expression and pathway levels. So, it is critical to understand the pathogenesis of dengue infection in terms of gene expression and the associated functions. METHODS: For this purpose, here, we have analyzed the temporal gene expression profiling for the dengue hemorrhagic fever dataset at 12, 24, and 48 hours. RESULTS: The outcome appears that the dengue hemorrhagic fever evolves differently at different time periods or stages. CONCLUSION: The change in the gene expression pattern increases exponentially from 12 hours to 48 hours and the number of altered functions (pathways) also increases. Wnt, apoptosis, and transcription signaling are among the critical pathways which are dominantly altered. In the initial phase (first 12 hours), only two pathways are altered due to dengue infection, while in the next 12 hours, eight pathways are altered, and finally, in the next 24 hours, 11 pathways are altered and most of these 11 pathways are very critical in terms of biological pathways and functions.

The Emergence of Human Pathogenic Coronaviruses: Lectins as Antivirals for SARS-CoV-2.

BACKGROUND: Human coronaviruses (HCoV) are common viruses and known to be associated with respiratory diseases, including pneumonia. Currently, seven human coronaviruses have been identified and known to cause upper and lower respiratory infections as well as nosocomial viral infections in humans. The bats, palm civets, and camels are identified as the reservoir of human coronaviruses. In 2002-2003, the emergence of SARS-CoV resulted in an outbreak and led towards the more awareness and importance of scientific research and medical urgency. METHODS: The recently identified SARS-CoV-2 was identified from the seafood market of the city Wuhan, China, in December 2019 and caused a global pandemic. This virus has now spread to more than 213 countries. This is the third highly pathogenic human coronavirus after SARS and MERS-CoV. The coronaviruses have RNA as genetic material and are known to have frequent recombination and mutations in their genome, which lead to the emergence and re-emergence of new virus strains and isolates with novel properties and extended hosts. The genetic mutations and suitable environmental conditions result in the emergence and re-emergence of pathogenic coronaviruses and cause a serious issue to human health and the economy globally. Lectins are the ubiquitous group of proteins that bind to glycosylated molecules. CONCLUSION: The plant lectins are known to have significant antiviral activities against coronaviruses. Additionally, the plant lectins can be used as potential therapeutics against bacteria, fungus, yeast, and protozoa. In this review, we have discussed the current status of human pathogenic coronavirus emergence and the use of plant lectins as antivirals against SARS-CoV-2.

COVID-19 Outbreak and Emerging Management through Pharmaceutical Therapeutic Strategy.

The latest SARS COV2 coronavirus contributes to a pandemic of millions of COVID-19. As there is no defensive immunity in humans and a virus can overcome inborn immune reaction, it can propagate unhindered, mostly in tissues contaminated. No unique therapies for COVID-19 contaminated patients are available at this time. The insights learned from previous respiratory viral infection control have given guidance into COVID- 19 therapy. Several complementary treatments have been tentatively introduced in hospital environments such as immune-modulators, antiviral, convalescent plasma transfusions and natural products. In COVID-19 patients, some of these therapies have provided substantial curative benefits. Moreover, numerous studies and clinical trials are being carried out in order to determine the efficacy of current pharmaceutical and natural products to establish possible therapeutic strategies for producing novel COVID-19 medicines. We summarized and defined the modes of mechanism, protection and efficacy on the existing therapeutic strategies for diseases linked to COVID-19 infection.

The Computational Intervention of Macrolide Antibiotics in the Treatment of COVID-19.

BACKGROUND: The spike (S) glycoprotein of SARS corona virus (SARS-CoV-2) and human Angiotensin- converting enzyme 2 (ACE2), are both considered the key factors for the initiation of virus infection. The present work is an effort for computational target to block the spike proteins (S) and ACE2 receptor proteins with Macrolide antibiotics like Azithromycin, (AZM), Clarithromycin (CLAM) and Erythromycin (ERY) along with RNA-dependent RNA polymerase (RdRp). METHODS: Three-dimensional structure of the SARS-CoV-2RdRp was built by the SWISS-MODEL server, the generated structure showed 96.35% identity to the available structure of SARS-Coronavirus NSP12 (6NUR), for model validity, we utilized the SWISS-model server quality parameters and Ramachandran plots. RESULTS: These compounds were able to block the residues (Arg553, Arg555, and Ala558) surrounding the deep grove catalytic site (Val557) of RdRp and thus plays an important role in tight blocking of enzyme active site. Reference drug Remdesivir was used to compare the docking score of antibiotics with RdRp. Docking value exhibited good binding energy (-7.7 up to -8.2 kcal/mol) with RdRp, indicating their potential as a potent RdRp inhibitor. Interaction of CLAM and ERY presented low binding energy (-6.8 and -6.6) with the ACE2 receptor. At the same time, CLAM exhibited a good binding affinity of -6.4 kcal/mol, making it an excellent tool to block the attachment of spike protein to ACE2 receptors. Macrolides not only affected the attachment to ACE2 but also blocked the spike proteins further, consequently inhibiting the internalization in the host cell. Three Alkyl bonds between Arg555, Ala558, and Met542 by CLAM and two Alkyl bonds of Arg624 and Lys621 by ERY plays an important role for RdRp inactivation, that can prevent the rise of newly budded progeny virus. These macrolides interacted with the main protease protein in the pocket responsible for the dimerization and catalytic function of this protein. The interaction occurred with residue Glu166, along with the catalytic residues (Tyr343, and His235) of Endoribonuclease (NSP15) protein. CONCLUSION: The present study gives three-way options either by blocking S proteins or ACE2 receptor proteins or inhibiting RdRp to counter any effect of COVID-19 by macrolide and could be useful in the treatment of COVID-19 till some better option available.

A Direct Method for RT-PCR Detection of SARS-CoV-2 in Clinical Samples.

INTRODUCTION: the emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic of acute respiratory disease (COVID-19). SARS-CoV-2 is a positive-strand RNA virus and its genomic characterization has played a vital role in the design of appropriate diagnostics tests. The current RT-PCR protocol for SARS-CoV-2 detects two regions of the viral genome, requiring RNA extraction and several hours. There is a need for fast, simple, and cost-effective detection strategies. METHODS: we optimized a protocol for direct RT-PCR detection of SARS-CoV-2 without the need for nucleic acid extraction. Nasopharyngeal samples were diluted to 1:3 using diethyl pyrocarbonate (DEPC)-treated water. The diluted samples were incubated at 95 °C for 5 min in a thermal cycler, followed by a cooling step at 4 °C for 5 min. Samples then underwent reverse transcription real-time RT-PCR in the E and RdRp genes. RESULTS: our direct detection protocol showed 100% concordance with the standard protocol with an average Ct value difference of 4.38 for the E region and 3.85 for the RdRp region. CONCLUSION: the direct PCR technique was found to be a reliable and sensitive method that can be used to reduce the time and cost of the assay by removing the need for RNA extraction. It enables the use of the assay in research, diagnostics, and screening for COVID-19 in regions with fewer economic resources, where supplies are more limited allowing for wider use for screening.

Coronavirus Disease -2019 (COVID-19) in 2020: A Perspective Study of a Global Pandemic.

Severe acute respiratory syndrome coronavirus (SARS-CoV-2) is responsible for the coronavirus disease- 2019 (COVID-19) pandemic, which was first reported from Wuhan, China, in late 2019. This infection spread to thousands of people globally within a short span of time with a progressive trend to mortality of citizens. Posing a potential public health threat, SARS-CoV-2 progressed from animal-to-human to human-tohuman transmission with symptoms ranging from little or no illness to persons being severely ill and many deaths, confirming two criteria for declaring COVID-19 a pandemic. The disease shows a progressive trend in symptomology, ranging from mild to severe pneumoniae to respiratory and multi-visceral failure that often leads to the death of patients with comorbidity within a short span of time. Intensive research efforts on different aspects of this human pathogen are underway across the globe for elucidating viral transmission routes and the mechanisms employed to overcome host defense responses. Due to the massive infective potential, studies are being carried out to develop effective diagnostics and therapeutic interventions, including re-purposing antivirals and other potential inhibitors. Herein, we describe the taxonomic classification of 'SARS-CoV-2', the structural organization of its genome, its infectivity, transmission, and receptor interaction; and we summarize risk assessment and approaches used for prevention of the infection. Finally, we discuss important aspects of the development of diagnostic tools and therapeutic countermeasures that have the potential to help in controlling the COVID-19 pandemic.

Natural Products: A Rich Source of Antiviral Drug Lead Candidates for the Management of COVID-19.

Today, the world is suffering from the pandemic of a novel coronavirus disease (COVID-19), a respiratory illness caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This pandemic is the third fatal coronavirus outbreak that has already occurred in the 21st century. Even six months after its emergence, hundreds of thousands of people are still being infected with SARS-CoV-2, and thousands of lives are lost every day across the world. No effective therapy has been approved to date for the treatment of this disease, suggesting the need to broaden the scope in the search for effective treatments. Throughout history, folk medicine has been successfully used to treat various ailments in humans, and Traditional Chinese Medicine has been instrumental in the containment of a number of viral diseases. Owing to their high chemical diversity and safety profiles, natural products offer great promises as potentially effective antiviral drugs. In recent years, a large number of anti-coronaviral phytochemicals with different mechanisms of action have been identified. Among them, tetra-O-galloyl-ß-D-glucose, caffeic acid, and saikosaponin B2 block viral entry. A number of flavonoids inhibit viral proteases. Silvestrol inhibits protein synthesis. Myricetin and scutellarein inhibit viral replication. Emodin, luteolin, and quercetin demonstrate anti-coronaviral activity by inhibiting multiple processes in the virus life cycle. In this review, we critically evaluate the findings of the natural product-based anticoronaviral research that has been published during the last two decades, and attempt to provide a comprehensive description about their utility as potential broad-spectrum anti-coronaviral drugs, examining leads that may guide/facilitate anti-SARS-CoV-2 drug development studies.

Impact of Traditional Plants and their Secondary Metabolites in the Discovery of COVID-19 Treatment.

BACKGROUND: Coronavirus Disease-2019 belongs to the family of viruses which cause serious pneumonia along with fever, breathing issues and infection of lungs, and was first reported in China and later spread worldwide. OBJECTIVE: Several studies and clinical trials have been conducted to identify potential drugs and vaccines for Coronavirus Disease-2019. The present study listed natural secondary metabolites identified from plant sources with antiviral properties and could be a safer and tolerable treatment for Coronavirus Disease-2019. METHODS: A comprehensive search on the reported studies was conducted using different search engines such as Google Scholar, SciFinder, Sciencedirect, Medline PubMed, and Scopus for the collection of research articles based on plant-derived secondary metabolites, herbal extracts, and traditional medicine for coronavirus infections. RESULTS: Status of COVID-19 worldwide and information of important molecular targets involved in COVID- 19 are described, and through literature search, it is highlighted that numerous plant species and their extracts possess antiviral properties and are studied with respect to coronavirus treatments. Chemical information, plant source, test system type with a mechanism of action for each secondary metabolite are also mentioned in this review paper. CONCLUSION: The present review has listed plants that have presented antiviral potential in the previous coronavirus pandemics and their secondary metabolites, which could be significant for the development of novel and a safer drug which could prevent and cure coronavirus infection worldwide.