Cohort 1 Percentage of patients with COVID-19 associated mild disease/moderate pneumonia progressing within 14 days after recruitment into severe pneumonia; defined as per most recent adapted WHO definition15 as follows : Clinical signs of pneumonia plus: • Oxygen saturation (SpO2) <90% on room air OR • Respiratory rate > 30 breaths/min Note: if WHO definitions change over the course of the recruitment phase of the trial; the trial definitions will be adapted accordingly. 2. Cohort 1 HH contacts - % of HH members that get infected with COVID19 during the 14 days following recruitment (defined as those RT-PCR and IgM/IgG negative at day 1 who become positive either by RT-PCR or IgM/IgG by day 14) 3. Cohort 2 - Percentage of COVID-19 associated severe pneumonia patients meeting the criteria of failure defined as worsening their condition over a 24h period (Increase by 1 point from baseline on a 7-point ordinal scale) or who die during hospitalization. The 7-point ordinal scale consists of: 1) Not hospitalised 2) Hospitalised – not on oxygen; no longer needs medical care 3) Hospitalised – not on oxygen; needs ongoing medical care 4) Hospitalised – on or requiring supplemental oxygen given by nasal cannula or face mask to maintain SpO2 and/or respiratory rate within normal range for age 5) Hospitalised – on or requiring non-invasive ventilation or high-flow oxygen devices to maintain SpO2 and/or respiratory rate within normal range for age 6) Hospitalised – on or requiring invasive ventilation OR failure of NIV/high flow oxygen devices to maintain SpO2 and/or respiratory rate within normal range for age 7) Death

Cohort 1 Percentage of patients with COVID-19 associated mild disease/moderate pneumonia progressing within 14 days after recruitment into severe pneumonia; defined as per most recent adapted WHO definition15 as follows : Clinical signs of pneumonia plus: • Oxygen saturation (SpO2) <90% on room air OR • Respiratory rate > 30 breaths/min Note: if WHO definitions change over the course of the recruitment phase of the trial; the trial definitions will be adapted accordingly. 2. Cohort 1 HH contacts - % of HH members that get infected with COVID19 during the 14 days following recruitment (defined as those RT-PCR and IgM/IgG negative at day 1 who become positive either by RT-PCR or IgM/IgG by day 14) 3. Cohort 2 - Percentage of COVID-19 associated severe pneumonia patients meeting the criteria of failure defined as worsening their condition over a 24h period (Increase by 1 point from baseline on a 7-point ordinal scale) or who die during hospitalization. The 7-point ordinal scale consists of: 1) Not hospitalised 2) Hospitalised – not on oxygen; no longer needs medical care 3) Hospitalised – not on oxygen; needs ongoing medical care 4) Hospitalised – on or requiring supplemental oxygen given by nasal cannula or face mask to maintain SpO2 and/or respiratory rate within normal range for age 5) Hospitalised – on or requiring non-invasive ventilation or high-flow oxygen devices to maintain SpO2 and/or respiratory rate within normal range for age 6) Hospitalised – on or requiring invasive ventilation OR failure of NIV/high flow oxygen devices to maintain SpO2 and/or respiratory rate within normal range for age 7) Death