COVID-19: Diagnosis and Management-Part II

The entire world has slowed down since the outbreak of a highly contagious virus, i.e., Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Extensive efforts are being made to reduce disease transmission, optimize the management strategy to reduce deaths and to come up with a vaccine as a preventive measure. Though several scientists across the globe are working tirelessly for developing an effective vaccine, it may still take several months to launch it successfully in the market. The behavioural interventions like maintenance of physical distancing (at least one meter), hand hygiene and cough etiquette, and use of personal protective equipment (PPE) are the currently available effective strategies to break the chain of disease transmission. All these interventions have been implemented at the population and individual level with or without linking with regulations. Based on the risk of exposure, provision and use of appropriate PPE is the need of the hour. The healthcare professionals working in COVID-19 areas have been recommended to use full PPE, which includes gloves, N-95 face masks, face shields, goggles, full-body gowns, and shoe covers. The general population has been asked to use homemade or triple-layered surgical masks in addition to the maintenance of physical distancing and hand hygiene. There are other additional strategies or measures which may or may not prevent the COVID-19 transmission. This chapter attempts to clarify the important and effective measures for the prevention of COVID-19 at the individual and community levels. It also tried to demystify the myths related to COVID-19.

The coronavirus disease (COVID-19) pandemic outbreak has created health havoc all over the world. Till now, no definite treatment has been found to combat the COVID-19 outbreak, probably due to a poor understanding of the molecular mechanism of this infection. As it’s a health devastating situation, so due to lack of proper time for research, clinicians all over the world are exploring the already approved drug such as lopinavir, ritonavir, chloroquine (CQ), hydroxychloroquine (HCQ), azithromycin (AZ), remdesivir, favipiravir, ribavirin, nitozoxanide, interferon- α (IFN), arbidol, corticosteroids, ivermectin, teicoplanin, herbal drugs, etc. for antiviral activity. Previous studies suggest that these drugs act by different mechanisms such as prevention of entry and fusion of the virus with host cell by blocking angiotensin-converting enzyme-2 (ACE-2) receptor and increasing endosomal pH respectively, inhibition of RNA polymerase and protease enzyme, inhibition of inflammatory pathway by blocking toll-like receptors (TLR’s), inhibition of RNA synthesis, interference of glycosylation of cellular receptor, suppression of immune response, etc. Besides these drugs, few humanized monoclonal antibodies such as tocilizumab and sarilumab are also shown to be effective against COVID-19 by blocking interleukin-6 (IL-6) receptors. In addition to these drugs, convalescent plasma therapy is also being used to treat COVID-19 patients. Focus is on the development of a vaccine for COVID-19 at the earliest and indeed, many vaccines are in various stages of the development process, with some under clinical trials. This review gives an exhaustive view of current therapeutic strategies for the management of COVID-19.

The novel coronavirus disease (COVID-19) has scourged the world ever since its outbreak in December 2019 in Wuhan, China. The disease tends to be asymptomatic or mild in nearly 80% of the patients. However, around 5% of the patients tend to have critical disease complicated by acute respiratory distress syndrome (ARDS), shock and multiple organ failure. Mortality in COVID-19, as represented by the case-fatality rate (CFR), is around 6% (as of June 4, 2020). The CFR of COVID-19 is lower as compared to other coronavirus-related diseases like the Severe Acute Respiratory Syndrome (SARS) and the Middle East Respiratory Syndrome (MERS), however, it is likely to increase as we reach the end of the pandemic. The CFR also varies widely from one nation to another with the maximum mortality being hitherto reported from the European nations and the least from Singapore, Cambodia, Vietnam and Iceland. The common causes of death in COVID- 19 include respiratory failure, consequently leading to ARDS, pulmonary thromboembolism, shock and multiple organ failure. Advancing age and presence of comorbid illness are consistently associated with an increased risk of death, while certain biochemical and hematological parameters, notably C-reactive protein, IL-6, cardiac troponin, D-dimer and absolute count can also help predict mortality in patients with COVID-19.

Coronavirus disease 2019 (COVID-19) is an acute respiratory illness. It is caused by a novel coronavirus (SARS-CoV-2). It has gained widespread recognition after it originated from China. The World Health Organisation (WHO) declared the outbreak of COVID-19 as an international public health emergency. Patients of COVID-19 develop long-time complications along with severe health problems as it majorly affects the respiratory system, utilizing angiotensin-converting enzyme 2. Characteristic symptoms include fever, cough, and dyspnea, although some patients may be asymptomatic. People need extensive care to be protected from anxiety and depression. This outbreak harmed various organ systems and led to the development of long-term complications such as respiratory failure, pneumonia, pancreatic complications, cardiac injury, secondary infections, renal disorders, disseminated intravascular coagulation, and rhabdomyolysis. Individuals with comorbidities are at higher risk of illness and mortality. The risk is also increasing in older people, especially people the age of 60-80 years or more. The most prevalent comorbidities are asthma, neurologic disorders, diabetes, obesity, cardiovascular disease, and malignancy/hematologic conditions. As there is no specific treatment available so far, therefore complications of this disease are also increased by the use of non-specific drugs. The recovery of these patients is another major challenge for health care professionals. So in this chapter, we will discuss long-term complications associated with COVID-19.

The current COVID-19 pandemic is a wake-up call pointing towards the vulnerability of humankind as it has outstretched its arms to almost all the continents, sparing few socially isolated ones. The highly contagious nature, ultra-stable genetic makeup, novel modifications in open reading frame (ORF) region, air-born route of transmission, and ability to cross the species barrier prove the potential of COVID-19 to elicit the global pandemic situation. In current times, when even known antibiotics for combating several diseases are being rendered inefficacious owing to the rising multidrug resistance among pathogenic strains, the panacea to a wide array of diseases can be vaccination. A prominent characteristic for COVID-19 vaccine development is that numerous technologies from lipid nanoparticle (LNP)-encapsulation, dendritic cells (DCs)-based vaccines, antigen-presenting cells (artificial-APCs)-based vaccines, and DNA plasmid-based platforms to viral vector approaches are being evaluated for the cause. Certain vaccine development technologies may be better suited for some parts of the global population, while others may prove to be more efficacious for the other population subtypes. This may not only be arising due to geographical or ethnic distinctions, but also physiological differences such as the presence of comorbidities, immune profile of subjects, etc. In this chapter, we attempt to bring forth the various approaches or molecular platforms that have been taken up or proposed for the development of a vaccine against coronavirus disease. We also attempt to elaborate on the pros and cons associated with each of the approaches that may be feasible due to the distinctions in the various population subtypes.

Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) or coronavirus disease or COVID-19 is a disease that has led to colossal mortality worldwide. The fast spread of this disease has caused havoc and panic among individuals, which has further worsened with the unavailability of vaccines or some proven drug regime. To date, only 12 new antiviral drugs have been approved by the FDA (8 against hepatitis C virus (2 in combinations for HIV). Thus, it becomes of utmost importance to identify drugs for new and re-emerging viruses, including the coronavirus. Considering the quest, we have put forth this book chapter to update readers about current repurposed and experimental drugs for this novel coronavirus. The viral lifecycle assisted in providing vital potential targets for drug therapy. The present chapter also deals with the existing mechanism of action of the drugs, their category, and clinical data reported.