COVID-19(5) multiplex(5) Nursing(4) antibody(4) Vaccine(4) Human(3) pertussis(3) coronavirus(3) serology(3) memory response(2) Specific antibody concentrations(2) conducted(2) Whole blood(2) Tetanus(2) Nurse(2) antigenicity(2) Pneumococcal polysaccharide antigens(2) Streptococcus pneumoniae(2) Vaccines(2) Healthcare professional(2) education(2) COVID-19 pandemic(2) mass cytometry(2) Microfluidic Evalution platform(2) DTaP(2) Antigen(2) cross-sectional(2) immunomodulation(2) resource(2) Diphtheria(2)