학술논문
A 2-month field cohort study of SARS-CoV-2 in saliva of BNT162b2 vaccinated nursing home workers
Document Type
Original Paper
Author
Saegerman, Claude; Diep, Anh Nguyet; Renault, Véronique; Donneau, Anne-Françoise; Stamatakis, Lambert; Coppieters, Wouter; Michel, Fabienne; Breuer, Christophe; Dandoy, Margaux; Ek, Olivier; Gourzones, Claire; Schyns, Joey; Goffin, Emeline; Minner, Frédéric; Durkin, Keith; Artesi, Maria; Bours, Vincent; Bureau, Fabrice; Gillet, Laurent
Source
Communications Medicine. 2(1)
Subject
Language
English
ISSN
2730-664X
Abstract
Background: Nursing home (NH) residents have been severely affected during the COVID-19 pandemic because of their age and underlying comorbidities. Infection and outbreaks in NHs are most likely triggered by infected workers. Screening for asymptomatic NH workers can prevent risky contact and viral transmission to the residents. This study examined the effect of the BNT162b2 mRNA COVID‑19 (Comirnaty® ; BioNTech and Pfizer) vaccination on the saliva excretion of SARS-CoV-2 among NH workers, through weekly saliva RT-qPCR testing.Methods: A 2-month cohort study was conducted among 99 NHs in the Walloon region (Belgium), at the start of February 2021. Three groups of workers, i.e., non-vaccinated (n = 1618), one-dosed vaccinated (n = 1454), and two-dosed vaccinated (n = 2379) of BNT162b2 mRNA COVID‑19 vaccine, were followed-up weekly. Their saliva samples were used to monitor the shedding of SARS-CoV-2. All positive samples were sequenced and genotyped to identify the circulating wild-type virus or variants of concern.Results: The protection fraction against the excretion of the SARS-CoV-2 in the saliva samples of the workers after the second dose is estimated at 0.90 (95% CI: 0.18; 0.99) at 1 week and 0.83 (95% CI: 0.54; 0.95) at 8 weeks. We observe more circulating SARS-CoV-2 and a greater variability of viral loads in the unvaccinated group compared to those of the vaccinated group.Conclusions: This field cohort study advances our knowledge of the efficacy of the mRNA BNT162b2 COVID-19 vaccine on the viral shedding in the saliva specimens of vaccinated NH workers, contributing to better decision-making in public health interventions and management.
Plain language summary: Nursing homes have been particularly affected by COVID-19 outbreaks with devastating consequences. Screening for SARS-CoV-2 infection in nursing home workers is therefore helpful to prevent transmission of the virus. It is also helpful in determining whether vaccination, which has been widely implemented in this population, is effective at reducing the number of SARS-CoV-2 infections. To this end, we tested saliva samples from workers from 99 nursing homes in the Walloon region of Belgium over a two-month period. Some workers had not been vaccinated and others had received one or two doses of the Pfizer-BioNTech BNT162b2 vaccine. We find that fully vaccinated individuals are significantly protected against SARS-CoV-2 infection compared to non-vaccinated individuals. These findings help to provide evidence that BNT162b2 vaccination is an effective measure to limit the infection of nursing home workers.
Saegerman et al. perform saliva SARS-CoV-2 testing in a cohort of nursing home workers in Belgium who are either unvaccinated or have received one or two doses of the BNT162b2 mRNA vaccine. The authors show that vaccination protects against shedding of SARS-CoV-2 into saliva and observe greater variability in viral load in the unvaccinated group.
Plain language summary: Nursing homes have been particularly affected by COVID-19 outbreaks with devastating consequences. Screening for SARS-CoV-2 infection in nursing home workers is therefore helpful to prevent transmission of the virus. It is also helpful in determining whether vaccination, which has been widely implemented in this population, is effective at reducing the number of SARS-CoV-2 infections. To this end, we tested saliva samples from workers from 99 nursing homes in the Walloon region of Belgium over a two-month period. Some workers had not been vaccinated and others had received one or two doses of the Pfizer-BioNTech BNT162b2 vaccine. We find that fully vaccinated individuals are significantly protected against SARS-CoV-2 infection compared to non-vaccinated individuals. These findings help to provide evidence that BNT162b2 vaccination is an effective measure to limit the infection of nursing home workers.
Saegerman et al. perform saliva SARS-CoV-2 testing in a cohort of nursing home workers in Belgium who are either unvaccinated or have received one or two doses of the BNT162b2 mRNA vaccine. The authors show that vaccination protects against shedding of SARS-CoV-2 into saliva and observe greater variability in viral load in the unvaccinated group.