The possible immunopathogenesis of SARS-Cov-2 Infection - A review of immune changes in patients with COVID-19

Abstract

A highly infectious outbreak of Coronavirus disease (COVID-19) caused by a new coronavirus - Severe Acute Respiratory Syndrome coronavirus 2 (SARS-CoV-2) was first officially reported in December 2019 in Wuhan, China which spread rapidly worldwide infecting millions of people in many countries. Although most of infected patients are asymptomatic or develop mild symptoms that usually recover with good prognosis, 10-20% of infected people especially old age and those with underlying medical co-morbidity conditions, develops severe disease with multiple organ failure, primarily respiratory failure and death. SARS-CoV-2 infection shares similar genetics, pathogenic, epidemiological and clinical features with two other viruses belonging to same coronavirus family that have caused serious infections over the last two decades i.e SARS-CoV (Severe Acute Respiratory Syndrome Coronavirus) and MERS-CoV (Middle East Respiratory Syndrome Coronavirus) and pathogenesis and immune changes observed in these infections can be applied to this new pandemic in order to learn the imperative role of the immune system during the course of coronavirus infections and possible use of immunomodulatory intervention and immunosuppressive drugs in management of severe patients. As the immunopathogenesis of SARS-CoV-2 infection is still not clear and understanding this underlying mechanism which leads to severe form of disease is important for identifying effective treatment for critically ill patients, this article reviews the immunopathogenic changes observed in SARS-CoV-2 infection and identify the possible mechanisms by which it induces immune changes including cytokine storm, in order to provide a reference for the early clinical identification and management of severe form of COVID-19 infection.