Diverse Manifestations of COVID-19: Some Suggested Mechanisms.

Md S Zaman,Robert C Sizemore

doi:10.3390/ijerph18189785

Abstract

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the cause of the novel respiratory disease COVID-19, has reached pandemic status and presents a wide range of manifestations of diverse magnitude, including fever, cough, shortness of breath, and damage to vital organs, such as the heart, lung, kidney, and brain. Normally, older individuals and those with underlying health issues are more at risk. However, about 40% of COVID-19 positive individuals are asymptomatic. This review aims to identify suggested mechanisms of diverse manifestations of COVID-19. Studies suggest that T cell-mediated immunity and specific and/or nonspecific immunity from other vaccines could protect against SARS-CoV-2. The potential role of cross-reacting antibodies to coronaviruses that cause the common cold, mumps virus, polio virus, and pneumococcal bacteria are also suggested to help protect against COVID-19. Decreased production of Type I interferons (IFN-α and IFN-β) could also be linked to COVID-19 manifestations. Several studies suggest that ACE2 cell membrane receptors are involved in SARS-CoV-2 infection. However, the relationship between an abundance of ACE2 receptors and the infectivity of the virus is unknown. Unlocking these manifestation mysteries could be crucial as this could help researchers better understand the virulence, pathology, and immune responses associated with SARS-CoV-2, leading to the development of effective therapies and treatment plans.

Highlights

Coronaviruses are a large family of viruses that are common in humans and several animals, such as cattle, camels, cats, and bats
From the very beginning of the coronavirus pandemic, scientists and health care workers were baffled about why some SARS-CoV-2 positive patients present mild-to-severe symptoms of COVID-19 infection, yet a significant segment of the infected population remains asymptomatic
Patients with COVID-19 have presented a wide range of symptoms and sequela [4,5,6]

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Coronaviruses that infect animals can evolve and cause human infections Common examples of such cases are two earlier viruses, SARS-CoV (Severe Acute Respiratory Syndrome) and MERS-CoV (Middle East Respiratory Syndrome), followed by the current virus SARS-CoV2. From the very beginning of the coronavirus pandemic, scientists and health care workers were baffled about why some SARS-CoV-2 positive patients present mild-to-severe symptoms of COVID-19 infection, yet a significant segment of the infected population remains asymptomatic. These silent spreaders can effectively transmit the virus and make the epidemic further difficult to control [10]. This paper will focus on what could be the explanation behind a large segment of the SARS-CoV-2 positive population not showing manifestations of the disease and how to comprehend the disproportionate infection and mortality rates among various world populations

COVID-19 Immunity from Other Unrelated Vaccinations

Memory T Cell-Mediated Immunity

Cross-Reacting Antibodies to Other Coronaviruses

Differences Due to Age

Findings

Discussion and Conclusions