Receptor binding domain‐IgG levels correlate with protection in residents facing SARS‐CoV‐2 B.1.1.7 outbreaks. Issue 6 (29th October 2021)

• Record Type: Journal Article
• Authors: Blain, Hubert; Tuaillon, Edouard; Gamon, Lucie; Pisoni, Amandine; Miot, Stéphanie; Delpui, Valentin; Si‐Mohamed, Nejm; Niel, Clémence; Rolland, Yves; Montes, Brigitte; Groc, Soraya; Rafasse, Sophia; Dupuy, Anne‐Marie; Gros, Nathalie; Muriaux, Delphine; Picot, Marie‐Christine; Bousquet, Jean
• Is Part Of: Allergy. Volume 77:Issue 6(2022)
• Page Start: 1885
• Page End: 1894
• Publication Date: 2021-10-29
• Subjects: antibody response -- BNT162b2 vaccine -- COVID‐19 -- efficacy -- neutralizing antibodies -- nucleocapsid antigenemia -- nursing homes -- residents -- SARS‐CoV‐2 -- symptoms; Allergy -- Periodicals; 616.97
• DOI: 10.1111/all.15142
• Languages: English
• ISSNs: 0105-4538

Abstract

Abstract: Background: Limited information exists on nursing home (NH) residents regarding BNT162b2 vaccine efficacy in preventing SARS‐CoV‐2 and severe COVID‐19, and its association with post‐vaccine humoral response. Methods: 396 residents from seven NHs suffering a SARS‐CoV‐2 B.1.1.7 (VOC‐α) outbreak at least 14 days after a vaccine campaign were repeatedly tested using SARS‐CoV‐2 real‐time reverse‐transcriptase polymerase chain reaction on nasopharyngeal swab test (RT‐qPCR). SARS‐CoV‐2 receptor‐binding domain (RBD) of the S1 subunit (RBD‐IgG) was measured in all residents. Nucleocapsid antigenemia (N‐Ag) was measured in RT‐qPCR‐positive residents and serum neutralizing antibodies in vaccinated residents from one NH. Results: The incidence of positive RT‐qPCR was lower in residents vaccinated by two doses (72/317; 22.7%) vs one dose (10/31; 32.3%) or non‐vaccinated residents (21/48; 43.7%; p < .01). COVID‐19–induced deaths were observed in 5 of the 48 non‐vaccinated residents (10.4%), in 2 of the 31 who had received one dose (6.4%), and in 3 of the 317 (0.9%) who had received two doses ( p = .0007). Severe symptoms were more common in infected non‐vaccinated residents (10/21; 47.6%) than in infected vaccinated residents (15/72; 21.0%; p = .002). Higher levels of RBD‐IgG ( n = 325) were associated with a lower SARS‐CoV‐2 incidence. No in vitro serum neutralization activity was found for RBD‐IgG levels below 1050 AU/ml. RBD‐IgG levels were inversely associated with N‐Ag levels, found as a risk factor of severe COVID‐19. Conclusions: Two BNT162b2 doses are associated with a 48% reduction of SARS‐CoV‐2 incidence and a 91.3% reduction of death risk in residents from NHs facing a VOC‐α outbreak. Post‐vaccine RBD‐IgG levels correlate with BNT162b2 protection against SARS‐CoV‐2 B.1.1.7. Abstract : This study assesses the incidence of positive SARS‐CoV‐2 B.1.1.7 by RT‐qPCR results according to the vaccination status in nursing home residents facing a VOC‐α outbreak. Two BNT162b2 doses are associated with a major reduction of SARS‐CoV‐2 B.1.1.7 incidence and COVID‐19. Post‐vaccine RBD‐IgG levels correlate with protection in this population.Abbreviations: AU/ml, arbitrary units per milliliter; AU/ml, arbitrary units per milliliter; COVID‐19, coronavirus disease 2019; RBD, receptor‐binding domain; RT‐qPCR, real‐time reverse‐transcriptase polymerase chain reaction; SARS‐CoV‐2, severe respiratory syndrome coronavirus 2; VOC, variant of concern