inclusion criteria: the following patients will be enrolled in the study under group 1: - age greater than and equal to 18 years - evidence of liver cirrhosis established during the clinical investigations and/or hospital stay, as evidenced by clinical, endoscopic, radiological and/or histological criteria. - baseline negative sars-cov19 igg neutralizing antibodies the following patients (healthy controls) will be enrolled in the study: - age greater than and equal to 18 years - baseline negative sars-cov19 igg neutralizing antibodies - no previous covid-19 infection - no major respiratory, cardiac comorbid illnesses or malignancy or immunosuppressed state

inclusion criteria: the following patients will be enrolled in the study under group 1: - age greater than and equal to 18 years - evidence of liver cirrhosis established during the clinical investigations and/or hospital stay, as evidenced by clinical, endoscopic, radiological and/or histological criteria. - baseline negative sars-cov19 igg neutralizing antibodies the following patients (healthy controls) will be enrolled in the study: - age greater than and equal to 18 years - baseline negative sars-cov19 igg neutralizing antibodies - no previous covid-19 infection - no major respiratory, cardiac comorbid illnesses or malignancy or immunosuppressed state

inclusion criteria: the following patients will be enrolled in the study under group 1: - age 18 to 60 years - evidence of liver cirrhosis established during the clinical investigations and/or hospital stay, as evidenced by clinical, endoscopic, radiological and/or histological criteria. - baseline negative sars-cov19 igg neutralizing antibodies the following patients (healthy controls) will be enrolled in the study: - age 18 to 60 years - baseline negative sars-cov19 igg neutralizing antibodies - no previous covid-19 infection - no major respiratory, cardiac comorbid illnesses or malignancy or immunosuppressed state

inclusion criteria: the following patients will be enrolled in the study under group 1: - age 18 to 60 years - evidence of liver cirrhosis established during the clinical investigations and/or hospital stay, as evidenced by clinical, endoscopic, radiological and/or histological criteria. - baseline negative sars-cov19 igg neutralizing antibodies the following patients (healthy controls) will be enrolled in the study: - age 18 to 60 years - baseline negative sars-cov19 igg neutralizing antibodies - no previous covid-19 infection - no major respiratory, cardiac comorbid illnesses or malignancy or immunosuppressed state