Review Article
Volume 10 Issue 4 - 2021
Understanding the Pathophysiology of COVID-19: A Review of Emerging Concepts
Oliver Ombeva Malande1,2,3*, Andrew M Musyoki4, Johanna Catharina Meyer3, Brian Godman3,5,6 and Jacob Masika7
1Department of Pediatrics and Child Health, Faculty of Health Sciences, Egerton University, Nakuru, Kenya
2Department of Pediatrics and Child Health, School of Medicine, Makerere University, Kampala, Uganda
3Division of Public Health Pharmacy and Management, School of Pharmacy, Sefako Makgatho Health Sciences University, Pretoria, South Africa
4Department of Microbiological Pathology, School of Medicine, Sefako Makgatho Health Sciences University, Pretoria, South Africa
5Division of Clinical Pharmacology, Karolinska Institute, Karolinska University Hospital Huddinge, Stockholm, Sweden
6Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, United Kingdom
7Department of Medical Physiology, School of Medicine, Kenyatta University, Kenya
*Corresponding Author: Oliver Ombeva Malande, Department of Pediatrics and Child Health, Faculty of Health Sciences, Egerton University, Nakuru, Kenya.
Received: February 18, 2021; Published: March 29, 2021


Coronavirus disease 2019 (COVID-19) was first described in the Chinese city of Wuhan in December 2019. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was identified as the causative agent. It was quickly established that SARS-CoV-2 is transmitted through respiratory droplets when individuals are in close contact with asymptomatic or symptomatic carriers. The incubation period is around 5 days, and it is estimated in up to 97% of infected individuals symptoms will present within 14 days. To date, new presentations are being described. COVID-19 presentation spans from asymptomatic, mild disease to severe systemic disease. The most commonly described symptoms include pneumonia, dyspnea, dry cough, headache and fever. Various technologists have developed quantitative polymerase chain reaction (PCR) assays for the detection of SARS-CoV-2 from mainly nasopharyngeal or throat swabs. Several serological tests have also now been approved for use. Whilist a lot has been learnt of the laboratory and clinical charac-teristics of this disease, questions still remain as to the actual pathophysiology leading to either asymptomatic, mild or severe disease. However, despite this, the disease carries the risk of sepsis and acute respiratory failure with increased number of deaths, forced social distance and lockdowns in many countries. This review highlights key mechanisms that have been proposed to contribute to COVID-19 progression from viral entry to multisystem organ failure, as well as the central role of the immune response in successful viral clearance or progression to death. With the exception of when there is a pre-existing comorbidity, most reports indicate severe disease occurring in the older population and mild disease or asymptomatic infection in children. Over 120 SARSCoV- 2 vaccines are at various stages of development. As the roll-out of approved vaccines is happening at different rates globally, the prescribed methods to reduce transmission remain facemasks, social distancing, and contact tracing.

Keywords: SARS-CoV-2; COVID-19; Pathophysiology; Cytokine Release Syndrome; Multisystem Organ Failure; Respiratory Failure


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Citation: Oliver Ombeva Malande., et al. “Understanding the Pathophysiology of COVID-19: A Review of Emerging Concepts”. EC Paediatrics 10.4 (2021): 22-30.

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