Spike Antibody Levels of Nursing Home Residents With or Without Prior COVID-19 3 Weeks After a Single BNT162b2 Vaccine Dose

Abstract

Recent studies have suggested that, to reach immunity, immunocompetent SARS-CoV-2 seropositive adults may only require 1 dose rather than 2 doses of a messenger RNA vaccine 1,2 ; however, these studies did not include older adults. Older adults living in nursing homes are at higher risk for severe COVID-19, and the immune response to the vaccine may differ from that of younger, healthier adults.We compared IgG antibody levels after a single dose of BNT162b2 (Pfizer-BioNTech) vaccine in nursing home residents with or without prior COVID-19.Methods | Between March and June 2020, we studied residents from nursing homes in Montpellier, France, facing a COVID-19 outbreak. 3 As soon as a resident developed COVID-19, the testing recommendations from the European Geriatric Medicine Society were followed 4 in that all residents were repeatedly tested using reverse transcriptase-polymerase chain reaction (RT-PCR) on nasopharyngeal swabs until no new cases were diagnosed. Participants provided written informed consent and the study was approved by the Montpellier University hospital institutional review board.Six weeks after the end of the outbreak, all residents underwent blood testing for levels of IgG antibody against the SARS-CoV-2 nucleocapsid (N) protein. 3 All residents from 6 nursing homes were offered a first vaccine dose in January 2021. Three weeks later, all residents underwent blood testing to quantitatively assess IgG antibody levels against the SARS-CoV-2 spike (S) protein and N protein. Levels of IgG antibody against the SARS-CoV-2 receptor-binding domain were quantified using the SARS-CoV-2 IgG II Quant assay (Abbott Diagnostics). The results were expressed as arbitrary units (AU)

High levels of anti–SARS-CoV-2 IgG antibodies in previously infected patients with cancer after a single dose of BNT 162b2 vaccine

“…Our results demonstrate that a single dose of mRNA vaccine induce high level of S-IgG in the majority of cancer patients with prior SARS-CoV-2 infection. These data are in line with two recent reports among nursing home residents and health care workers previously infected with SARS-CoV-2 [4,5]. However, immunogenicity in cancer patients without previous infection was lower after one dose, but significantly increased within 3 weeks of a BNT162b2 vaccine boost at day 21 after the first dose.…”

Differences in the Concentration of Anti-SARS-CoV-2 IgG Antibodies Post-COVID-19 Recovery or Post-Vaccination

“…Hence the need to conduct special serological surveillance in people aged 65+ or with coexisting chronic diseases, and perhaps to consider the need to take further doses to ensure protective properties. Blain et al [34] focused on a group of nursing home residents and confirmed that one dose of an mRNA vaccine may also be sufficient. At the same time, they pointed out that testing the level of antibodies with neutralizing properties should be carried out for these patients, especially for those with an unknown history of infection.…”

Study of neutralizing [anti-RBD] antibody responses induced by COVID-19 vaccines in healthcare professionals in a diagnostic centre of Central India

“…13 In a study on 102 residents of a nursing home in France, 36 residents with history of previous Covid infection were found to be positive for S protein IgG while 49.2% showed good immune response after vaccination. 14 In a study by Bradley et al, 15 the level of blocking antibodies were shown to be higher in recently infected group as compared to sero negative individuals. Our study correlates with this study.…”