The proportion of subjects admitted to the intensive care unit from day 1 to day 30; based on at least one of the following criteria1. rapid progression over hours2. lack of improvement in oxygen with high flow >40L/min or non-invasive ventilation with a proportion of inhaled oxygen (FiO2) > 0.63. developing hypercapnea or increased work of breathing that does not respond to increased oxygen despite maximum standard therapy available outside the ICU4. haemodynamic instability or multi-organ failure with maximum standard care available outside the ICU

The proportion of subjects admitted to the intensive care unit from day 1 to day 30; based on at least one of the following criteria1. rapid progression over hours2. lack of improvement in oxygen with high flow >40L/min or non-invasive ventilation with a proportion of inhaled oxygen (FiO2) > 0.63. developing hypercapnea or increased work of breathing that does not respond to increased oxygen despite maximum standard therapy available outside the ICU4. haemodynamic instability or multi-organ failure with maximum standard care available outside the ICU