General Inclusion Criteria:  Eastern Cooperative Oncology Group < 3 Vaccination with 2 doses of Coronavac vaccine  General Exclusion Criteria:  Previous SARS-CoV-2 infection Vaccination with Coronavac more than 12 weeks before informed consent Intravenous immunoglobulin therapy 60 days before informed consent Any condition, that could interfere with the participant's participation during the study in the opinion of the treating investigator.  Cancer Cohort  Inclusion Criteria:  Diagnosis of cancer in the previous 5 years (consistent biopsy is required). Life expectancy more than 12 weeks  Exclusion Criteria:  Bone marrow transplant, solid organ recipient, HIV, immunosuppressant treatment for other condition.  Bone Marrow Transplant Cohort  Inclusion Criteria:  Bone marrow transplant between January 2019 and December 2020  Exclusion Criteria:  Other cancer diagnosis during the last 5 years, solid organ recipient, HIV, immunosuppressant treatment for other condition.  Solid Organ Recipient Cohort:  Inclusion Criteria:  Liver, kidney or heart transplant between January 2019 and December 2020 Active immunosuppressant treatment  Exclusion Criteria:  - Cancer diagnosis during the last 5 years, bone marrow transplant, immunosuppressant treatment for other condition, HIV  HIV Cohort:  Inclusion Criteria:  CD4 <= 500 cels/mm3 documented one year before study enrollment Active antiretroviral therapy Viral load < 200 copies/ml  Exclusion Criteria:  Cancer diagnosis during the last 5 years, bone marrow transplant or solid organ recipient, immunosuppressant treatment.  Rheumatic Disease Cohort  Inclusion Criteria:  Diagnosis of rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, relapsing polychondritis, Behcet disease or juvenile idiopathic arthritis Chronic immunomodulatory treatment with anti-TNF, anti-IL6 or anti-IL17 agents  Exclusion Criteria:  Treatment with more than one biological agent. Cancer diagnosis during the last 5 years, bone marrow transplant or solid organ recipient, HIV diagnosis.