Low But Recoverable Markers of Humoral Immune Response to BNT162b2 in Elderly LTCF Residents Five to Seven Months After Two-Dose Vaccination

Abstract

The immune response is known to wane after vaccination with BNT162b2, but the role of age, morbidity and body composition is not well understood. We conducted a cross-sectional study in long-term care facilities (LTCFs) for the elderly. All study participants had completed two-dose vaccination with BNT162b2 five to 7 months before sample collection. In 298 residents (median age 86 years, range 75–101), anti-SARS-CoV-2 rector binding IgG antibody (anti-RBD-IgG) concentrations were low and inversely correlated with age (mean 51.60 BAU/ml). We compared the results to Health Care Workers (HCW) aged 18–70 years (n = 114, median age: 53 years), who had a higher mean anti-RBD-IgG concentration of 156.99 BAU/ml. Neutralization against the Delta variant was low in both groups (9.5% in LTCF residents and 31.6% in HCWs). The Charlson Comorbidity Index was inversely correlated with anti-RBD-IgG, but not the body mass index (BMI). A control group of 14 LTCF residents with known breakthrough infection had significant higher antibody concentrations (mean 3,199.65 BAU/ml), and 85.7% had detectable neutralization against the Delta variant. Our results demonstrate low but recoverable markers of immunity in LTCF residents five to 7 months after vaccination.

Retrospective Cohort Study of the Effectiveness of the Sputnik V and EpiVacCorona Vaccines against the SARS-CoV-2 Delta Variant in Moscow (June–July 2021)

“…The protective effect of the vaccine may thus be shorter. These hypotheses are partially supported by the literature [ 43 , 44 , 45 , 57 ].…”

Limited neutralisation of the SARS-CoV-2 Omicron subvariants BA.1 and BA.2 by convalescent and vaccine serum and monoclonal antibodies

“…In our study, the cohorts of BNT162b2 double-vaccinated and double-vaccinated individuals with a breakthrough infection had a significant ( p < 0.0001) higher age (85.5 mean years, SD: 6.9) compared to the boosted groups (40.8 mean years, SD: 12.1 and 43.6 mean years, SD: 11.3, respectively), as these samples derived from a study (No 20-864) conducted in long-term care facilities for the elderly. 29 The mean age of all other groups was comparable ( Table 1 , Figure 2 b).…”

“…Samples from double BNT162b2-vaccinated (2xBNT 6m ) and sera from double BNT162b2-vaccinated and SARS-CoV-2 infected individuals (2xBNT/SARS-CoV-2 infection 4m ) were obtained from the Impfcare study. 29 Sera from triple BNT162b2-vaccinated individuals (2xBNT/BNT 0.5m and 2xBNT/BNT 3m ) and sera from double mRNA-1273 vaccinated and additionally BNT162b2-boosted (2xMOD/BNT 0.5m ) individuals were obtained from an internal study at the University Hospital Frankfurt (Frankfurt am Main, Germany). Sera from double mRNA-1273 vaccinated (2xMOD 6m ) individuals were obtained from an internal study at the University Hospital Frankfurt (Frankfurt am Main, Germany) and a heterologous vaccination study (unpublished).…”

Characterization of the Antibody and Interferon-Gamma Release Response after a Second COVID-19 Booster Vaccination

“…However, the protection against in vitro infections, as measured with neutralization assays, is limited against immune-escape-associated VOCs such as Omicron BA.1 and BA.2 [ 6 , 32 ]. In consequence, the finding that booster vaccinations led to increased but low levels of nABs suggests that at-risk individuals such as the elderly who show prominent immune waning could benefit from regular vaccine doses [ 35 ]. The positive effect of regular vaccination of the healthy population might be restricted, as currently, the infection rate of Omicron remains high and the burden of disease lower than in previous variants.…”