ABSTRACT
Since its emergence, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread worldwide, and led to ever-increasing mortality. SARS-CoV-2 infection perturbs the function of the body's vital organs, making patients of all ages susceptible to the disease. Nevertheless, individuals developing critical illness with poor outcomes were mostly the elderly and people with co-morbid conditions, who constituted the vast majority of coronavirus disease 2019 (COVID-19) fatalities. Complications of COVID-19 mostly involve the respiratory, renal and cardiovascular systems, and in severe cases secondary infections leading to pneumonia and acute respiratory distress syndrome, which may precede the death of the patient. Multi-organ failure in individuals with COVID-19 could be a consequence of their co-morbidities. A patient's pre-existing conditions may affect the disease prognosis, requiring immediate attention to accurately detect and evaluate them in SARS-CoV-2-infected individuals. This review addresses several issues in relation to manifestations of the body's vital organs along with potential diagnostic blood factors in SARS-CoV-2 infection. It is hoped that the review will lead to more comprehensive understanding of this complex disease.