inclusion criteria: * age ≥ 18 years; * informed consent form signed by the patient or guardian or by audio with the guardian; * positive result for covid-19 in pcr (polymerase chain reaction) in nasopharyngeal swab or tracheal secretion up to 10 days before the inclusion and radiological evidence of covid-19, by chest radiography or chest computed tomography; * need for ≥ 4 l of supplemental oxygen to maintain peripheral oxygen saturation equal to or greater than 93% or need for invasive mechanical ventilation.

inclusion criteria: * age ≥ 18 years; * informed consent form signed by the patient or guardian or by audio with the guardian; * positive result for covid-19 in pcr (polymerase chain reaction) in nasopharyngeal swab or tracheal secretion up to 10 days before the inclusion and radiological evidence of covid-19, by chest radiography or chest computed tomography; * need for ≥ 4 l of supplemental oxygen to maintain peripheral oxygen saturation equal to or greater than 93% or need for invasive mechanical ventilation.

inclusion criteria: - age ≥ 18 years; - informed consent form signed by the patient or guardian or by audio with the guardian; - positive result for covid-19 in pcr (polymerase chain reaction) in nasopharyngeal swab or tracheal secretion up to 10 days before the inclusion and radiological evidence of covid-19, by chest radiography or chest computed tomography; - need for ≥ 4 l of supplemental oxygen to maintain peripheral oxygen saturation equal to or greater than 93% or need for invasive mechanical ventilation.

inclusion criteria: - age ≥ 18 years; - informed consent form signed by the patient or guardian or by audio with the guardian; - positive result for covid-19 in pcr (polymerase chain reaction) in nasopharyngeal swab or tracheal secretion up to 10 days before the inclusion and radiological evidence of covid-19, by chest radiography or chest computed tomography; - need for ≥ 4 l of supplemental oxygen to maintain peripheral oxygen saturation equal to or greater than 93% or need for invasive mechanical ventilation.