Review of Burden, Clinical Definitions, and Management of COVID-19 Cases

Abstract

Our understanding of SARS-CoV-2, the virus responsible for coronavirus disease 2019 (COVID-19), its clinical manifestations, and treatment options continues to evolve at an unparalleled pace. This review sought to summarize the key literature regarding transmission, case definitions, clinical management, and the burden of COVID-19. Our review of the literature showed that SARS-CoV-2 was mainly transmitted via inhalation of respiratory droplets containing the virus and had a mean incubation period of 4-6 days. The commonly reported symptoms were fever (75.3% ± 18.7%) and cough (62.6% ± 17.7%) across the spectrum of clinical disease-mild, moderate, severe, and critical, but with the disease phenotype varying with severity. Categorization of these cases for home care or hospital management needs to be defined, with risk stratification accounting for the age of the patient and the presence of underlying comorbidities. The case definitions varied among countries, which could have contributed to the differences in the case fatality rates among affected countries. The severity and risk of death due to COVID-19 was associated with age and underlying comorbidities. Asymptomatic cases, which constitute 40-80% of COVID-19 cases are a considerable threat to control efforts. The presence of fever and cough may be sufficient to warrant COVID-19 testing, but using these symptoms in isolation will miss a proportion of cases. A clear definition of a COVID-19 case is essential for the management, treatment, and tracking of clinical illness, and to inform the quarantine measures and social distancing that can help control the spread of SARS-CoV-2.

Overweight/obesity as the potentially most important lifestyle factor associated with signs of pneumonia in COVID-19

“…What determines whether or not pneumonia develops in the course of COVID-19 remains to be fully understood (2). Several risk factors for COVID-19 related death have already been identified, such as older age, male sex and preexisting comorbidities (3).…”

Genomic Cues From Beta-Coronaviruses and Mammalian Hosts Sheds Light on Probable Origins and Infectivity of SARS-CoV-2 Causing COVID-19

“…Integrins are ubiquitous and located on nucleated cells (Lowell and Mayadas, 2012), which may explain why SARS-CoV-2 can establish extrapulmonary, enteric and possibly, systemic infections (Wang W. et al, 2020;Zang et al, 2020). This extensive cellular tropism may explain its higher infectivity compared to SARS-CoV and likely play a role in the pathogenesis and the typical spectrum of clinical disease associated with COVID-19 (Mcarthur et al, 2020). Phylogenetic relatedness of coronaviruses causing infections in mammals.…”

“…SARS-CoV-2, a beta-coronavirus ( Figure 1A ), causes coronavirus disease 2019, simply called COVID-19 (Chan et al, 2020 ; Zhu et al, 2020 ). The pathogenesis and clinical outcome of SARS-CoV-2 infection is similar to SARS with fever, cough, and shortness of breath being the most commonly reported symptoms (Mcarthur et al, 2020 ). SARS-CoV-2 is now pandemic and has infected more than 12 million people and caused more than half a million deaths globally.…”

General characteristics of the Human Coronavirus (HCoVs) and the new coronavirus (SARS-CoV-2) that produces COVID-19 illness.

“…Patients with diabetes mellitus, hypertension, chronic diseases or kidney problems should be carefully monitored for any organic deterioration and have care that patients do not acquire opportunistic infections. 16,52 There is not specific antiviral drugs against COVID-19, however some treatment with antivirals and adjunctive therapies as convalescent plasma, tocilizumab, azithromycin and corticosteroids are used as supportive care for COVID-19 patients with promising results as described below:…”