inclusion criteria: * adult patients ≥ 18 years old, * hospitalized with a proven diagnosis of covid-19 (sars-cov-2 positive in rtpcr), in medicine or in intensive care. * with a need for oxygen therapy ≥ 2 l / min to maintain a sp02\> 92% or a need for oxygen therapy to maintain a pao2 / fio2\> 300 mmhg (for intubated patients). * with a chest scanner at least 7 days after the onset of symptoms, and whose centralized interpretation shows a ct scan aspect suggestive of intense and predominant dad which can explain the patient's oxygen dependence. * signature of a free, written and informed consent by the patient, or the person of trust * affiliate or beneficiary of a social security scheme.

inclusion criteria: * adult patients ≥ 18 years old, * hospitalized with a proven diagnosis of covid-19 (sars-cov-2 positive in rtpcr), in medicine or in intensive care. * with a need for oxygen therapy ≥ 2 l / min to maintain a sp02\> 92% or a need for oxygen therapy to maintain a pao2 / fio2\> 300 mmhg (for intubated patients). * with a chest scanner at least 7 days after the onset of symptoms, and whose centralized interpretation shows a ct scan aspect suggestive of intense and predominant dad which can explain the patient's oxygen dependence. * signature of a free, written and informed consent by the patient, or the person of trust * affiliate or beneficiary of a social security scheme.

inclusion criteria: - adult patients ≥ 18 years old, - hospitalized with a proven diagnosis of covid-19 (sars-cov-2 positive in rtpcr), in medicine or in intensive care. - with a need for oxygen therapy ≥ 2 l / min to maintain a sp02> 92% or a need for oxygen therapy to maintain a pao2 / fio2> 300 mmhg (for intubated patients). - with a chest scanner at least 7 days after the onset of symptoms, and whose centralized interpretation shows a ct scan aspect suggestive of intense and predominant dad which can explain the patient's oxygen dependence. - signature of a free, written and informed consent by the patient, or the person of trust - affiliate or beneficiary of a social security scheme.

inclusion criteria: - adult patients ≥ 18 years old, - hospitalized with a proven diagnosis of covid-19 (sars-cov-2 positive in rtpcr), in medicine or in intensive care. - with a need for oxygen therapy ≥ 2 l / min to maintain a sp02> 92% or a need for oxygen therapy to maintain a pao2 / fio2> 300 mmhg (for intubated patients). - with a chest scanner at least 7 days after the onset of symptoms, and whose centralized interpretation shows a ct scan aspect suggestive of intense and predominant dad which can explain the patient's oxygen dependence. - signature of a free, written and informed consent by the patient, or the person of trust - affiliate or beneficiary of a social security scheme.