Current inclusion criteria as of 29/07/2021: 1. Patient informed consent form (ICF) signed 2. Aged =18 and =64 years at the time of the signature of ICF 3. Subjects who are willing to comply with the requirements of the study protocol, attend scheduled visits and calls for the duration of the study by telephone contact 4. Mild Symptomatic Individuals with COVID-19 confirmed by polymerase chain reaction (PCR) based on WHO guideline (version as of 27/05/2020). In the study will be enrolled COVID-19 patient with RT-PCR Ct value =30 for =2 genes out of 4, at the first swab. The enrollment of COVID-19 vaccinated patients will be allowed if they will present a “clinical vaccination failure”, defined according to the indications reported in the “Global Manual on Surveillance of AE Following Immunization” (WHO guidelines) 5. Onset of symptoms from not more than 2/3 days Previous inclusion criteria: 1. Patient informed consent form (ICF) signed 2. Aged =18 and <64 years at the time of the signature of ICF 3. Subjects who are willing to comply with the requirements of the study protocol, attend scheduled visits and calls for the duration of the study by telephone contact 4. Mild Symptomatic Individuals with COVID-19 confirmed by polymerase chain reaction (PCR) based on WHO guideline (version as of 27/05/2020). In the study will be enrolled COVID-19 patient with RT-PCR Ct value <30 for =2 genes out of 4, at the first swab. 5. Onset of symptoms from not more than 2/3 days

Current inclusion criteria as of 29/07/2021: 1. Patient informed consent form (ICF) signed 2. Aged =18 and =64 years at the time of the signature of ICF 3. Subjects who are willing to comply with the requirements of the study protocol, attend scheduled visits and calls for the duration of the study by telephone contact 4. Mild Symptomatic Individuals with COVID-19 confirmed by polymerase chain reaction (PCR) based on WHO guideline (version as of 27/05/2020). In the study will be enrolled COVID-19 patient with RT-PCR Ct value =30 for =2 genes out of 4, at the first swab. The enrollment of COVID-19 vaccinated patients will be allowed if they will present a “clinical vaccination failure”, defined according to the indications reported in the “Global Manual on Surveillance of AE Following Immunization” (WHO guidelines) 5. Onset of symptoms from not more than 2/3 days Previous inclusion criteria: 1. Patient informed consent form (ICF) signed 2. Aged =18 and <64 years at the time of the signature of ICF 3. Subjects who are willing to comply with the requirements of the study protocol, attend scheduled visits and calls for the duration of the study by telephone contact 4. Mild Symptomatic Individuals with COVID-19 confirmed by polymerase chain reaction (PCR) based on WHO guideline (version as of 27/05/2020). In the study will be enrolled COVID-19 patient with RT-PCR Ct value <30 for =2 genes out of 4, at the first swab. 5. Onset of symptoms from not more than 2/3 days

1. Patient informed consent form (ICF) signed 2. Aged =18 and <64 years at the time of the signature of ICF 3. Subjects who are willing to comply with the requirements of the study protocol, attend scheduled visits and calls for the duration of the study by telephone contact 4. Mild Symptomatic Individuals with COVID-19 confirmed by polymerase chain reaction (PCR) based on WHO guideline (version as of 27/05/2020). In the study will be enrolled COVID-19 patient with RT-PCR Ct value <30 for =2 genes out of 4, at the first swab. 5. Onset of symptoms from not more than 2/3 days

1. Patient informed consent form (ICF) signed 2. Aged =18 and <64 years at the time of the signature of ICF 3. Subjects who are willing to comply with the requirements of the study protocol, attend scheduled visits and calls for the duration of the study by telephone contact 4. Mild Symptomatic Individuals with COVID-19 confirmed by polymerase chain reaction (PCR) based on WHO guideline (version as of 27/05/2020). In the study will be enrolled COVID-19 patient with RT-PCR Ct value <30 for =2 genes out of 4, at the first swab. 5. Onset of symptoms from not more than 2/3 days