inclusion criteria: 1. age ≥ 18 years 2. having received a first dose of one of the two mrna vaccines (pfizer-biontech or moderna) as recommended. 3. for whom a 2nd dose of mrna vaccine is planned within 4 to 6 weeks (according to the recommendations of the has and the ansm). 4. without a history of sars-cov-2 infection (negative pcr, negative antigen test or negative chest ct or sars-cov-2 serology) 5. healthy or in stable health if pre-existing medical history. stable health is defined as an existing disease that has not required a significant change in treatment or hospitalisation for worsening in the 3 months prior to inclusion, and for which neither a significant change in treatment or hospitalisation for worsening of the disease is envisaged in the near future 6. able to understand and comply with the research procedures as judged by the investigator 7. informed consent signed by the participant and the investigator. 8. person affiliated to a social security scheme.

inclusion criteria: 1. age ≥ 18 years 2. having received a first dose of one of the two mrna vaccines (pfizer-biontech or moderna) as recommended. 3. for whom a 2nd dose of mrna vaccine is planned within 4 to 6 weeks (according to the recommendations of the has and the ansm). 4. without a history of sars-cov-2 infection (negative pcr, negative antigen test or negative chest ct or sars-cov-2 serology) 5. healthy or in stable health if pre-existing medical history. stable health is defined as an existing disease that has not required a significant change in treatment or hospitalisation for worsening in the 3 months prior to inclusion, and for which neither a significant change in treatment or hospitalisation for worsening of the disease is envisaged in the near future 6. able to understand and comply with the research procedures as judged by the investigator 7. informed consent signed by the participant and the investigator. 8. person affiliated to a social security scheme.

inclusion criteria: age ≥ 18 years having received a first dose of one of the two mrna vaccines (pfizer-biontech or moderna) as recommended. for whom a 2nd dose of mrna vaccine is planned within 4 to 6 weeks (according to the recommendations of the has and the ansm). without a history of sars-cov-2 infection (negative pcr, negative antigen test or negative chest ct or sars-cov-2 serology) healthy or in stable health if pre-existing medical history. stable health is defined as an existing disease that has not required a significant change in treatment or hospitalisation for worsening in the 3 months prior to inclusion, and for which neither a significant change in treatment or hospitalisation for worsening of the disease is envisaged in the near future able to understand and comply with the research procedures as judged by the investigator informed consent signed by the participant and the investigator. person affiliated to a social security scheme.

inclusion criteria: age ≥ 18 years having received a first dose of one of the two mrna vaccines (pfizer-biontech or moderna) as recommended. for whom a 2nd dose of mrna vaccine is planned within 4 to 6 weeks (according to the recommendations of the has and the ansm). without a history of sars-cov-2 infection (negative pcr, negative antigen test or negative chest ct or sars-cov-2 serology) healthy or in stable health if pre-existing medical history. stable health is defined as an existing disease that has not required a significant change in treatment or hospitalisation for worsening in the 3 months prior to inclusion, and for which neither a significant change in treatment or hospitalisation for worsening of the disease is envisaged in the near future able to understand and comply with the research procedures as judged by the investigator informed consent signed by the participant and the investigator. person affiliated to a social security scheme.

inclusion criteria: 1. age ≥ 18 years 2. having received a first dose of one of the two mrna vaccines (pfizer-biontech or moderna) as recommended. 3. for whom a 2nd dose of mrna vaccine is planned within 4 to 6 weeks (according to the recommendations of the has and the ansm). 4. without a history of sars-cov-2 infection (negative pcr, negative antigen test or negative chest ct or sars-cov-2 serology) 5. healthy or in stable health if pre-existing medical history. stable health is defined as an existing disease that has not required a significant change in treatment or hospitalisation for worsening in the 3 months prior to inclusion, and for which neither a significant change in treatment or hospitalisation for worsening of the disease is envisaged in the near future 6. able to understand and comply with the research procedures as judged by the investigator 7. informed consent signed by the participant and the investigator. 8. person affiliated to a social security scheme.

inclusion criteria: 1. age ≥ 18 years 2. having received a first dose of one of the two mrna vaccines (pfizer-biontech or moderna) as recommended. 3. for whom a 2nd dose of mrna vaccine is planned within 4 to 6 weeks (according to the recommendations of the has and the ansm). 4. without a history of sars-cov-2 infection (negative pcr, negative antigen test or negative chest ct or sars-cov-2 serology) 5. healthy or in stable health if pre-existing medical history. stable health is defined as an existing disease that has not required a significant change in treatment or hospitalisation for worsening in the 3 months prior to inclusion, and for which neither a significant change in treatment or hospitalisation for worsening of the disease is envisaged in the near future 6. able to understand and comply with the research procedures as judged by the investigator 7. informed consent signed by the participant and the investigator. 8. person affiliated to a social security scheme.