participants will not be included in the study if they present (reported by the research participants): * known allergy to components of influenza and mmr vaccines or serious adverse events to previous administration. * fever (\> 38 degrees celsius) in the last 24 hours. * pregnancy. note: pregnancy should be avoided for one month after vaccination. * symptoms of active viral or bacterial infection. * documented diagnosis of covid-19. * vaccination in the last 4 weeks against sars-cov-2. * immunocompromised participants. this exclusion category includes: a) infection with the human immunodeficiency virus (hiv-1); b) neutropenic participant with less than 500 neutrophils/mm3; c) participant with organ transplantation; d) participants with bone marrow transplantation; e) participants in chemotherapy treatment; f) participants with primary immunodeficiency; g) participants with severe lymphopenia with less than 400 lymphocytes/mm3; h) treatment with any anti-cytokine medication; i) treatment with oral or intravenous steroids, for example, daily doses of prednisone or equivalent for more than 3 months, or probable use of oral or intravenous steroids within next four weeks. * some type of lymphoma or malignancy in the previous two years. * direct involvement in the design or execution of the study. * absence from work for more than 4 weeks within the next 12 weeks after study admission (vacation, maternity leave, retirement, planned surgery, etc.)

participants will not be included in the study if they present (reported by the research participants): * known allergy to components of influenza and mmr vaccines or serious adverse events to previous administration. * fever (\> 38 degrees celsius) in the last 24 hours. * pregnancy. note: pregnancy should be avoided for one month after vaccination. * symptoms of active viral or bacterial infection. * documented diagnosis of covid-19. * vaccination in the last 4 weeks against sars-cov-2. * immunocompromised participants. this exclusion category includes: a) infection with the human immunodeficiency virus (hiv-1); b) neutropenic participant with less than 500 neutrophils/mm3; c) participant with organ transplantation; d) participants with bone marrow transplantation; e) participants in chemotherapy treatment; f) participants with primary immunodeficiency; g) participants with severe lymphopenia with less than 400 lymphocytes/mm3; h) treatment with any anti-cytokine medication; i) treatment with oral or intravenous steroids, for example, daily doses of prednisone or equivalent for more than 3 months, or probable use of oral or intravenous steroids within next four weeks. * some type of lymphoma or malignancy in the previous two years. * direct involvement in the design or execution of the study. * absence from work for more than 4 weeks within the next 12 weeks after study admission (vacation, maternity leave, retirement, planned surgery, etc.)

participants will not be included in the study if they present (reported by the research participants): known allergy to components of influenza and mmr vaccines or serious adverse events to previous administration. fever (> 38 degrees celsius) in the last 24 hours. pregnancy. note: pregnancy should be avoided for one month after vaccination. symptoms of active viral or bacterial infection. documented diagnosis of covid-19. vaccination in the last 4 weeks against sars-cov-2. immunocompromised participants. this exclusion category includes: a) infection with the human immunodeficiency virus (hiv-1); b) neutropenic participant with less than 500 neutrophils/mm3; c) participant with organ transplantation; d) participants with bone marrow transplantation; e) participants in chemotherapy treatment; f) participants with primary immunodeficiency; g) participants with severe lymphopenia with less than 400 lymphocytes/mm3; h) treatment with any anti-cytokine medication; i) treatment with oral or intravenous steroids, for example, daily doses of prednisone or equivalent for more than 3 months, or probable use of oral or intravenous steroids within next four weeks. some type of lymphoma or malignancy in the previous two years. direct involvement in the design or execution of the study. absence from work for more than 4 weeks within the next 12 weeks after study admission (vacation, maternity leave, retirement, planned surgery, etc.)

participants will not be included in the study if they present (reported by the research participants): known allergy to components of influenza and mmr vaccines or serious adverse events to previous administration. fever (> 38 degrees celsius) in the last 24 hours. pregnancy. note: pregnancy should be avoided for one month after vaccination. symptoms of active viral or bacterial infection. documented diagnosis of covid-19. vaccination in the last 4 weeks against sars-cov-2. immunocompromised participants. this exclusion category includes: a) infection with the human immunodeficiency virus (hiv-1); b) neutropenic participant with less than 500 neutrophils/mm3; c) participant with organ transplantation; d) participants with bone marrow transplantation; e) participants in chemotherapy treatment; f) participants with primary immunodeficiency; g) participants with severe lymphopenia with less than 400 lymphocytes/mm3; h) treatment with any anti-cytokine medication; i) treatment with oral or intravenous steroids, for example, daily doses of prednisone or equivalent for more than 3 months, or probable use of oral or intravenous steroids within next four weeks. some type of lymphoma or malignancy in the previous two years. direct involvement in the design or execution of the study. absence from work for more than 4 weeks within the next 12 weeks after study admission (vacation, maternity leave, retirement, planned surgery, etc.)