Acta Scientific Microbiology (ISSN: 2581-3226)

Review Article Volume 4 Issue 8

Coronavirus Disease 2019: A Review of Risk Factors, Severity, and Complications

Sabah Mohamed Alharazy*

Independent Researcher, Malaysia

*Corresponding Author: Sabah Mohamed Alharazy, Independent Researcher, Malaysia.

Received: June 15, 2021; Published: July 13, 2021


  The world is still facing the coronavirus disease 2019 (COVID-19) pandemic caused by coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), since it first appeared in Wuhan, China, in December 2019. The virus primarily affects the respiratory system, but increasing evidence indicates that SARS-CoV-2 can affect multiple organ systems and causes several complications. The risk factors for disease severity and complications of COVID-19 include cancer, cerebrovascular disease, chronic kidney disease, chronic obstructive pulmonary disease (COPD), and other lung diseases, diabetes mellitus, down syndrome, heart conditions, human immunodeficiency virus (HIV) infection, neurologic conditions, obesity, pregnancy, smoking, sickle cell disease, solid organ or blood stem cell transplantation, substance use disorders, use of corticosteroids or other immunosuppressive medications. Since older people have one or more coexisting medical conditions, they are probably at the highest risk for fatal COVID-19 infections. COVID-19 disease severity can range from mild to critical, with the majority having only mild disease. The most common complication of this disease is acute respiratory distress syndrome (ARDS). Other complications include cardiovascular, renal, neurologic, thrombotic complications, liver injury, as well as bacterial, viral, and fungal coinfections. This review summarizes the current understanding of the risk factors, the severity of COVID-19 infection, and the most common complications of this disease.

Keywords: Coronavirus Disease 2019 (COVID-19); Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2); Risk Factors; Severity; Complications; Severe Acute Respiratory Distress Syndrome


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Citation: Sabah Mohamed Alharazy. “Coronavirus Disease 2019: A Review of Risk Factors, Severity, and Complications”. Acta Scientific Microbiology 4.8 (2021): 41-52.


Copyright: © 2021 Sabah Mohamed Alharazy. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.


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