inclusion criteria: * patients ≥18 years old. * laboratory-confirmed sars-cov-2 infection: infection confirmed with nasopharyngeal swab by positive rt pcr in the last 48 hours. * hospital admission for covid-19 in the previous 48 hours. * clinical stage 3 (no supplemental oxygen requirement) or 4 (supplemental oxygen requirement for nasal contact lenses or mask) of the who classification (see annex 2). * the patient must be able and willing to provide informed written consent before performing study procedures. * patient confirmed to covid19 as positive by positive pcr test

inclusion criteria: * patients ≥18 years old. * laboratory-confirmed sars-cov-2 infection: infection confirmed with nasopharyngeal swab by positive rt pcr in the last 48 hours. * hospital admission for covid-19 in the previous 48 hours. * clinical stage 3 (no supplemental oxygen requirement) or 4 (supplemental oxygen requirement for nasal contact lenses or mask) of the who classification (see annex 2). * the patient must be able and willing to provide informed written consent before performing study procedures. * patient confirmed to covid19 as positive by positive pcr test

inclusion criteria: - patients ≥18 years old. - laboratory-confirmed sars-cov-2 infection: infection confirmed with nasopharyngeal swab by positive rt pcr in the last 48 hours. - hospital admission for covid-19 in the previous 48 hours. - clinical stage 3 (no supplemental oxygen requirement) or 4 (supplemental oxygen requirement for nasal contact lenses or mask) of the who classification (see annex 2). - the patient must be able and willing to provide informed written consent before performing study procedures. - patient confirmed to covid19 as positive by positive pcr test

inclusion criteria: - patients ≥18 years old. - laboratory-confirmed sars-cov-2 infection: infection confirmed with nasopharyngeal swab by positive rt pcr in the last 48 hours. - hospital admission for covid-19 in the previous 48 hours. - clinical stage 3 (no supplemental oxygen requirement) or 4 (supplemental oxygen requirement for nasal contact lenses or mask) of the who classification (see annex 2). - the patient must be able and willing to provide informed written consent before performing study procedures. - patient confirmed to covid19 as positive by positive pcr test