Declining Prevalence of SARS-CoV-2 Antibodies among Vaccinated Nursing Home Residents and Staff Six Months after the Primary BNT162b2 Vaccination Campaign in Belgium: A Prospective Cohort Study, Meyers, Eline, Deschepper Ellen, Duysburgh Els, De Rop Liselore, De Burghgraeve Tine, Van Ngoc Pauline, Digregorio Marina, Delogne Simon, Coen Anja, De Clercq Nele, et al. , Viruses, Jan-11-2022, Volume 14, Issue 11, (2022)