Decreased antibody response after SARS-CoV-2 vaccination in patients with Down Syndrome

Abstract The risk of a severe course of SARS-CoV-2 infection in adults with Down syndrome is increased, resulting in an up to 10-fold increase in mortality, in particular in those over 40 years of age. After primary SARS-CoV-2 vaccination the higher risks remain. In this prospective observational cohort study, SARS-CoV-2 spike S1-specific antibody responses after routine SARS-CoV-2 vaccination (BNT162b2, mRNA-1273 or ChAdOx1) in adults with Down syndrome and healthy controls were compared. Adults with Down syndrome showed lower antibody concentrations after two mRNA vaccinations or after two ChAdOx1 vaccinations. After two mRNA vaccinations lower antibody concentrations were seen with increasing age.