**1. Introduction**

To date (August 2022), over 600,114,721 have been detected worldwide as positive COVID-19 cases with more than ~6,470,118 deaths in 228 countries [1]. In 2002–2003, the globe was first exposed to coronavirus through severe acute respiratory syndrome (SARS), and in 2011, it was first exposed to middle east respiratory syndrome (MERS) [2]. Then, toward the end of 2019, the current coronavirus (SARS-CoV-2) COVID-19 emerged in Wuhan, China [3]. COVID-19 is a contagious respiratory disease caused by the coronavirus 2 (SARS-CoV-2) that causes severe acute respiratory syndrome [4]. The virus is mostly transmitted by droplets and direct contact [5].

The disease's clinical symptoms are diverse, ranging from asymptomatic to severe illness, up to 20% of symptomatic individuals facing a high risk of mortality [6].

Critical illnesses include acute respiratory distress syndrome, septic shock, coagulopathies, refractory metabolic acidosis, and multi-organ dysfunction [7, 8]. Worse clinical outcomes have been linked to older age, male sex, and comorbidities [9]. To date, the factors associated with the disease severity of COVID-19 have not been clearly identified. It was demonstrated that both viral and host factors are implicated in treatment outcomes [10]. However, the pathogenesis of COVID-19 is closely associated with host factors, particularly cellular immunity in patients [11].
