No naive resident had detectable neutralizing Ab to the B.1.351 variant. These poor responses involved lower levels of IgG to all domains of the vaccine antigen, lower avidity of RBD IgG, and lower levels of Ab neutralizing the vaccine strain. ResultsSARS-CoV-2 naive residents had lower Ab responses to BNT162b2 mRNA vaccination than naive staff. Binding antibodies (Ab) to SARS-CoV-2 receptor binding domain (RBD), spike domains S1 and S2, RBD Ab avidity, and neutralizing Ab against SARS-CoV-2 wild type and B.1.351 variant were assessed at days 0, 21, 28, and 49. MethodsForty residents and forty staff members either naive or previously infected with SARS-CoV-2 were recruited in two NH in Belgium before immunization with two doses of 30g BNT162b2 mRNA vaccine at day 0 and day 21.
Ariën Virology Unit, Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium Department of Biomedical Sciences, University of Antwerp, An Maria E Goossens SD Epidemiology and Public Health, Sciensano, Anderlecht, Belgium.Stanislas Goriely Institute for Medical Immunology and ULB Center for Research in Immunology (U-CRI), Université libre de Bruxelles (ULB), Gosselies, Belgium.Margaret E Ackerman Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 USA.Joshua Alex Weiner Thayer School of Engineering, Dartmouth College, Hanover, NH 03755 USA.Katelijne Dierick SD Infectious Diseases in Humans, Sciensano, Ukkel, Belgium.Isabelle Thomas SD Infectious Diseases in Humans, Sciensano, Ukkel, Belgium.André Matagne Institute for Medical Immunology and ULB Center for Research in Immunology (U-CRI), Université libre de Bruxelles (ULB), Gosselies, Belgium.Mathieu Verbrugghe Mensura EDPB, Occupational Health Service, Antwerp, Belgium.Marie-Noëlle Schmickler Mensura EDPB, Occupational Health Service, Antwerp, Belgium.Steven Van Gucht SD Infectious Diseases in Humans, Sciensano, Ukkel, Belgium.Maan Zrein InfYnity Biomarkers, Lyon, France.
Marc Van Den Bulcke SD Epidemiology and Public Health, Sciensano, Anderlecht, Belgium.Antoine Francotte SD Infectious Diseases in Humans, Sciensano, Ukkel, Belgium.Johan Michiels Virology Unit, Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.Daphnée Georges Institute for Medical Immunology and ULB Center for Research in Immunology (U-CRI), Université libre de Bruxelles (ULB), Gosselies, Belgium.Sara Vande Kerckhove SD Infectious Diseases in Humans, Sciensano, Ukkel, Belgium.Leo Heyndrickx Virology Unit, Department of Biomedical Sciences, Institute of Tropical Medicine, Antwerp, Belgium.Stéphane De Craeye SD Infectious Diseases in Humans, Sciensano, Ukkel, Belgium.Kristof Y Neven SD Epidemiology and Public Health, Sciensano, Anderlecht, Belgium.Pieter Pannus SD Epidemiology and Public Health, Sciensano, Anderlecht, Belgium.