Table 1.

Clinical disease spectrum in patients with COVID-19.

Illness severity	Clinical signs or symptoms
Asymptomatic or pre-symptomatic patients	Viral positive (RT-PCR or NAAT) without any symptoms
Mild illness	Patients with COVID-19 symptoms, without dyspnea, shortness of breath
Moderate illness *	Clinical or imaging assessment showing COVID-19 pneumonia with oxygen saturation (SpO2) >94% at room air or sea level
Severe illness *	Respiratory rate >30 per minute, SpO2 < 94% on room air or at sea level, ratio of arterial partial pressure of oxygen to fraction of inspired oxygen (PaO2/FiO2) < 300, or chest X-ray showing lung infiltrates with >50% involvement
Critical illness *	Patients with respiratory failure, septic shock, or multiorgan dysfunction

COVID-19-corona virus disease 2019; NAAT- nucleic acid amplification test, RT-PCR- reverse transcriptase polymerase chain reaction.* Disease severity that might require an imaging with chest X-ray, CT chest, or CT pulmonary angiogram depending on the clinical assessment and disease status