Coronaviruses

Coronavirus disease 2019 (COVID-19) has been a major global health crisis since the influenza pandemic of 1918. Based on data from in vitro studies, traditional antimalarial agents, chloroquine and hydroxychloroquine, have been proposed as potential treatment options for patients with COVID-19. Both these medications have also been noted to prolong the QT interval, which increases the risk of drug-induced torsade de pointes (TdP) or sudden cardiac death (SCD) when used in non-COVID-19 patients. We reviewed the published clinical studies evaluating the QT interval in COVID-19 patients treated with chloroquine/hydroxychloroquine with or without azithromycin. A literature search using Google Scholar, and PubMed was done for studies published from December 2019 to September 2020. Studies with no specific description of the QT interval were excluded from this review. We identified twelve studies that qualified our criteria, which included 2595 patients. This review addresses the pathophysiology of QT prolongation and the incidence of the magnitude of QT prolongation associated with these medications when used in the treatment of patients admitted with COVID-19. Although most incidences of QT prolongation occurred two or more days after the initiation of these medications, early events of QT prolongation on the first day of therapy have also been reported. Notably, the combination of chloroquine/hydroxychloroquine with azithromycin was associated with a higher incidence of QT prolongation. Although QT prolongation is evident in all the described studies, none of these studies were designed to address the risk of QT prolongation associated with these medications in the outpatient setting or when used as prophylaxis against COVID-19. With the currently available literature, caution with close monitoring of the QT interval is advised when using these antimalarial agents in patients hospitalized with COVID-19 infection.

The recent outbreak of Severe Acute Respiratory Syndrome CoronaVirus 2 (SARS-CoV-2), from Wuhan, China, has turned out to be a global pandemic after sustained human to human transmission. While developed nations like the USA, Spain, Italy, Germany, and so forth have not been able to handle the episode, the situation at the moment is devastating in the South Asian Association for Regional Cooperation Countries, popularly known as SAARC countries. The present report is an attempt to understand the measurable correlation of the coronavirus cases, casualties, and mortality rates in the SAARC nations. It also analyses the drugs being tested in these countries to battle against the deadly virus. Moreover, the response of SAARC nations against COVID-19 and the effect of lockdown on daily life, economy, environment, and education have been discussed. Finally, to mitigate the COVID-19 pandemic, a strategy has been chalked down based on the knowledge obtained from the rest of the world.

The novel coronavirus infection (COVID-19) that emerged from Wuhan, China in December 2019 caused a global health crisis. With confirmed cases worldwide exceeding 40 million and continuing to grow, many research groups have been working to develop therapeutics and vaccines against COVID-19. In fact, some vaccine candidates are currently being tested in the clinical phase. The primary target of most of the studies is the spike glycoprotein of the SARS-CoV-2 virus, which binds to ACE2 receptors and allowing the virus entry to the host cells for the initiation of infection. Drugs such as Hydroxychloroquine and Favipiravir only aim to minimize symptoms but cause severe side effects in patients. On the other hand, neutralizing antibodies represents an important strategy for the treatment of COVID-19. Therapeutic neutralizing antibodies against SARS-CoV-2 spike protein can induce antibodies to block virus binding and fusion, thus inhibiting viral infection. Clinical studies show that antibodies obtained from plasma of recovered patients can improve prognosis and increase the survival rate. However, obtaining a high amount of plasmabased antibodies is a major problem in practice, therefore there is an urgent need to develop and produce reliable, high-yield, and specific antibodies against COVID-19. Instead of convalescent plasma therapy, monoclonal antibodies, and other antibodybased therapies such as IgY antibodies, camelid antibodies/nanobodies offer a promising alternative. In this chapter, a perspective on antibody-based approaches currently developed against SARS-CoV-2 by given some fundamental knowledge about these neutralizing antibodies and their potential for the treatment of COVID-19 is presented.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) belongs to the coronavirus family and is responsible for coronavirus disease 2019 (Covid-19 is a new animal origin communicate or infectious disease). The first case of Covid19 was reported in Wuhan, China, in December 2019, and due to its rapid increase and high incidence rate, it has become a pandemic health problem worldwide. It mainly attacks the host's immune system and impairs the regulation system, playing a significant role in its pathogenesis, causing covid-19 disease. Still, we are waiting for such molecules that can act as immunomodulators and enhance the body's immune system against the disease. This literature-based chapter was prepared by searching numerous relevant SCI and SCOPUS articles on the SARS-CoV-2 and COVID-19, herbal formulation and its active molecules from different databases like- Google Scholar, PubMed, and ResearchGate. Here, we were trying to highlight or repurpose several Immunomodulators (Alkaloids, Glycosides, Flavonoids, Sapogenins, and Curcumin) of plant origin. Plant-derived Immunomodulators are capable of stimulating/suppressing the components of the host immune system and both innate and adaptive immune responses. However, in this present review, we will discuss some phytoactive chemicals, which act as immunomodulators, and their immunomodulation mechanism in the host. Hopefully, this work shall encourage the researcher community to undertake further work on plant-based antiviral therapy with potential immunomodulatory activity, which might be responsible for modulating the host immune system to cure Covid-19. Besides, we discuss the further prospect of this study.

The outbreak of COVID-19 in China and its gradual spread over the entire globe, irrespective of age, sex or origin, has posed a major threat to the health of the entire human population. Investigations subsequent to the virus outbreak revealed that the unknown etiology was a novel coronavirus, later referred to as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The treatment and survival of patients have been largely dependent on an accurate diagnosis of this infection, both in symptomatic and asymptomatic individuals. Thus, highly sensitive and specific laboratory diagnostic methods are imperative for the accurate diagnosis of this condition. This manuscript focuses on various molecular and diagnostic imaging tools for reliable diagnosis of COVID-19 and the correlation of their outcomes with those from previous coronavirus epidemics. The molecular diagnostic tools include real-time reverse transcription polymerase chain reaction (rRT-PCR), ELISA based detection of early humoral response and DNA sequencing. The manuscript will also focus on national and international policies of testing, additional developments, issues and challenges faced in the diagnosis of COVID-19. The chapter will, therefore, highlight the current regime followed, developments and the probable lacunae that, if overcome, could improve the diagnostic schema of this disease.

COVID-19 is an infectious as well as contagious disease caused by severe acute respiratory syndrome (SARS) - Cov2 virus. As of date there is no specific treatment for coronavirus infection. Only symptomatic treatment is given to corona positive patients. Herd immunity is a natural phenomenon providing indirect protection against infectious diseases that are contagious. The principle behind herd immunity is that if enough immune persons are present in a community, then that will interrupt the transmission of an infectious agent and provide indirect protection for susceptible or unimmunized individuals. There are two ways to achieve herd immunity, either by mass vaccination or by allowing the disease to make its round through the population. Since vaccine development is a time taking process, herd immunity can be achieved by unleashing the virus in a controlled way. Sweden is the world leader of herd immunity in the fight against the corona virus. However, there are limitations to using herd immunity worldwide to stop the spread of this novel corona virus.