The objective of this multicenter observational study is to describe respiratory sequelae of COVID-19 patients hospitalized for severe pneumonia requiring oxygen supply.

Main objective To assess respiratory sequelae after SARS-CoV-2 infection in hospitalized patients with severe pneumonia requiring oxygen supply and followed up for 6 months after hospital discharge (see primary and secondary outcomes).

Secondary objectives

To describe pulmonary sequelae according to :

• the unit in which the patient was hospitalized,
• the maximum oxygen flow rate required during hospitalization,
• McCabe score,
• age,
• tobacco consumption,
• biological data (e.g. blood count, CRP, fibrinogen, LDH, albumin, D-dimer, ferritin),
• number of days from onset of symptoms to hospitalization,
• co-morbidities (e.g. diabetes, hypertension, coronary artery disease/heart failure, mild to moderate COPD/respiratory failure, overweight),
• concomitant treatments (e.g. non-steroidal anti-inflammatory drugs, corticosteroids, immunosuppressants, ACE inhibitors)
• specific drug treatments administered to treat COVID-19 infection,
• non-drug treatments (invasive ventilation, non-invasive ventilation, postural treatment) to manage respiratory disorders of COVID-19 infection.

To assess the impact of factors of social inequality on the severity of COVID-19 infection.

Conduct of research Patients who have been hospitalized for severe pneumonia due to CoV-2 SARS infection will be seen in consultation at approximately 3 and 6 months after hospital discharge, as per standard practice.

Inclusion criteria:

• Age ≥ 18 years old
• SARS-CoV-2 infection proven by RT-PCR and/or retrospective serology and/or a COVID-19 syndrome with evocative chest CT scan
• Hospitalized for severe pneumonia due to SARS-CoV-2 infection requiring oxygen supply

Exclusion criteria:

• Not hospitalized for a severe COVID-19 infection
• Absence of respiratory symptoms at V1 (3 months after hospital discharge), defined as: absence of residual exertional dyspnea and persistent pulmonary infiltrates on follow-up chest radiography at 1 month (if available), transcutaneous oxyhemoglobin saturation >94% and normal pulmonary auscultation
• Patient with pre-existing chronic lung disease prior to the first episode of COVID-19: chronic obstructive pulmonary disease confirmed by respiratory function testing with a forced expiratory volume in one second (FEV1) < 50% and/or a diffusing capacity for carbon monoxide (DLCO) < 60%, fibrotic lung disease or chronic respiratory failure (on long-term oxygen therapy)
• Opposition to participation in the study
• Patient under legal protection
• Patient not affiliated to/beneficiary of a social security scheme

Patients who have been hospitalized for severe pneumonia due to SARS-CoV-2 infection will be seen in consultation at approximately 3 and 6 months after hospital discharge, as per standard practice.