Abbreviations
SARS-CoV-2: Severe acute respiratory syndrome coronavirus 2; ARDS: Acute respiratory distress syndrome; COVID-19: Coronavirus disease 2019; RT-qPCR: Quantitative reverse transcription polymerase chain reaction; anti-NP: Anti-nucleocapsid protein; anti-S-RBD: Anti-spike protein receptor binding domain; OD- olfactory dysfunction, VL: viral load; hCOV- human coronaviruses; TDI: threshold (T), discrimination (D) and identification (I); MFI: mean fluorescence intensity, -ve: negative, +ve: positive, Ct -cycle threshold