1. Subjects with acute febrile or infectious disease at the time of the vaccine application or in the 7 days prior to its administration. 2. Subjects that meet any of the following criteria: a) Previous or current history of SARS-CoV 2 infection. b) SARS-CoV 2 PCR positive. c) Be declared in the category of contact or suspect at the time of inclusion. 3. Subjects with a history of hypersensitivity to Thiomersal or any of the components of the formulations. 4. Subjects with a history of having been immunized with a SARS-CoV 2 vaccine. 5. Subjects with a history of having received a vaccine from the Cuban immunization scheme, in a period of less than 30 days prior to the administration of the product under investigation. 6. Use of any investigational product in the 30 days prior to immunization. 7. Application of vaccines containing tetanus toxoid in the last 3 months. 8. History of chronic diseases. 9. Subjects with a history of major congenital malformations (defects that have a significant functional compromise for the individual's life, have medical consequences and require early, sometimes urgent, care). 10. Primary or secondary immune system disease. 11. History of neoplastic disease. 12. History of severe allergic reactions. 13. Treatment with immunomodulators in the last 30 days (eg steroids (except topical and inhaled), Interferon, Immunoferon, Nasalferon, Transfer Factor, monoclonal antibody, Biomodulin T, any ganmaglobulin, Heberferon, Thymosin, Levamisole). 14. Subjects with a history of Convulsive Disease. 15. History of treatment with blood products such as blood cell, plasma, whole blood or platelet concentrate transfusions in the last 4 months. 16. Splenectomy or splenic dysfunction. 17. Child with a minor or mentally disabled mother or father. 18. Pregnancy or lactation (a pregnancy test will be carried out before inclusion and administration of each dose to all girls and adolescents who menstruate). 19. Subjects with tattoos in the deltoid region of both arms. 20. Subjects with a history or positive results for: antibodies against HIV1 + 2, antibodies against hepatitis C, surface antigen of the hepatitis B virus or VDRL serology. 21. History of psychoactive substance use in the last 6 months. Exclusion criteria to be considered for the evaluation of the duration of the response and the safety and immunogenicity of the booster dose: 1. Subject who has caused interruption in the SOBERANA PEDIATRIA study 2. Subjects with a history of having received any vaccine against SARS-CoV 2 in addition to the heterologous schedule applied in the clinical trial. 3. Subject with a positive SARS-CoV-2 antigen test at the time prior to the administration of the booster dose or convalescent (diagnosis made by PCR) 4. Subjects with febrile or acute infectious disease at the time of vaccine application or in the 7 days prior to its administration 5. Subjects with a history of having received any vaccine from the Cuban immunization schedule, in a period of less than 30 days prior to the administration of the booster dose 6. Use of any investigational product in the 30 days prior to the administration of the booster dose 7. Treatment with immunomodulators in the last 30 days (e.g. steroids (except topical and inhaled), Interferon, Immunoferon, Nasalferon, Transfer Factor, monoclonal antibody, Biomodulin T, any ganmaglobulin, Heberferon, Thymosin, Levamisole). (3rd stage) 8. History of treatment with blood products such as transfusions of red blood cells, plasma, whole blood or platelet concentrate in the 4 months prior to the administration of the booster dose 9. Pregnancy or breastfeeding at the time of the booster vaccine application 10. Subjects with tattoos in the deltoid region of both arms. 11. History of consumption of psychoactive substances in the last 6 months.