Table 1.

Classification of COVID‐19 disease severity^†

Mild illness	Adults not presenting any clinical features suggestive of moderate or severe disease or a complicated course of illness. Characteristics: no symptoms or mild upper respiratory tract symptoms or cough, new myalgia or asthenia without new shortness of breath or a reduction in oxygen saturation
Moderate illness	Stable adult patient presenting with respiratory and/or systemic symptoms or signs. Able to maintain oxygen saturation above 92% (or above 90% for patients with chronic lung disease) with up to 4 L/min oxygen via nasal prongs. Characteristics: prostration, severe asthenia, fever> 38°C or persistent cough clinical or radiological signs of lung involvement no clinical or laboratory indicators of clinical severity or respiratory impairment
Severe illness	Adult patients meeting any of the following criteria: respiratory rate ≥ 30 breaths/min oxygen saturation ≤ 92% at a rest state arterial partial pressure of oxygen (PaO2)/ inspired oxygen fraction (FiO2) ≤300
Critical illness	Adult patient meeting any of the following criteria: Respiratory failure Occurrence of severe respiratory failure (PaO2/FiO2 < 200), respiratory distress or acute respiratory distress syndrome (ARDS). This includes patients deteriorating despite advanced forms of respiratory support (noninvasive ventilation, high‐flow nasal oxygen) OR patients requiring mechanical ventilation. OR other signs of significant deterioration hypotension or shock impairment of consciousness other organ failure

^†Recommendations were current at the time of writing. Please visit The National COVID‐19 Clinical Evidence Taskforce (https://covid19evidence.net.au/) for the latest updates to the recommendations.