inclusion criteria: * subject male or female age ≥ 75, or ≥ 60 if dementia * subject infected with covid 19 (confirmed by rt-pcr sars-cov-2 detectable less than 5 days old and clinical picture) * clinical manifestation of covid 19 requiring hospitalization: pneumopathy and/or upper airway infection and/or respiratory distress, confusion and/or encephalopathy and/or signs of encephalitis, walking disorders with ataxia and/or falls, digestive problem (diarrhea and/or vomiting) * subject affiliated to a social health insurance scheme * subject capable of understanding the objectives and risks of the research and of giving dated and signed informed consent, or agreement given by a trusted person, guardian or trustee. * subject who has been informed of the results of the prior medical examination

inclusion criteria: * subject male or female age ≥ 75, or ≥ 60 if dementia * subject infected with covid 19 (confirmed by rt-pcr sars-cov-2 detectable less than 5 days old and clinical picture) * clinical manifestation of covid 19 requiring hospitalization: pneumopathy and/or upper airway infection and/or respiratory distress, confusion and/or encephalopathy and/or signs of encephalitis, walking disorders with ataxia and/or falls, digestive problem (diarrhea and/or vomiting) * subject affiliated to a social health insurance scheme * subject capable of understanding the objectives and risks of the research and of giving dated and signed informed consent, or agreement given by a trusted person, guardian or trustee. * subject who has been informed of the results of the prior medical examination

inclusion criteria: - subject male or female age ≥ 75, or ≥ 60 if dementia - subject infected with covid 19 (confirmed by rt-pcr sars-cov-2 detectable less than 5 days old and clinical picture) - clinical manifestation of covid 19 requiring hospitalization: pneumopathy and/or upper airway infection and/or respiratory distress, confusion and/or encephalopathy and/or signs of encephalitis, walking disorders with ataxia and/or falls, digestive problem (diarrhea and/or vomiting) - subject affiliated to a social health insurance scheme - subject capable of understanding the objectives and risks of the research and of giving dated and signed informed consent, or agreement given by a trusted person, guardian or trustee. - subject who has been informed of the results of the prior medical examination

inclusion criteria: - subject male or female age ≥ 75, or ≥ 60 if dementia - subject infected with covid 19 (confirmed by rt-pcr sars-cov-2 detectable less than 5 days old and clinical picture) - clinical manifestation of covid 19 requiring hospitalization: pneumopathy and/or upper airway infection and/or respiratory distress, confusion and/or encephalopathy and/or signs of encephalitis, walking disorders with ataxia and/or falls, digestive problem (diarrhea and/or vomiting) - subject affiliated to a social health insurance scheme - subject capable of understanding the objectives and risks of the research and of giving dated and signed informed consent, or agreement given by a trusted person, guardian or trustee. - subject who has been informed of the results of the prior medical examination