Back to Search Start Over

SARS-CoV-2 cross-sectional seroprevalence study among public school staff in Metro Vancouver after the first Omicron wave in British Columbia, Canada.

Authors :
Watts AW
Mâsse LC
Goldfarb DM
Irvine MA
Hutchison SM
Muttucomaroe L
Poon B
Barakauskas VE
O'Reilly C
Bosman E
Reicherz F
Coombs D
Pitblado M
O'Brien SF
Lavoie PM
Source :
BMJ open [BMJ Open] 2023 Jun 12; Vol. 13 (6), pp. e071228. Date of Electronic Publication: 2023 Jun 12.
Publication Year :
2023

Abstract

Objective: To determine the SARS-CoV-2 seroprevalence among school workers within the Greater Vancouver area, British Columbia, Canada, after the first Omicron wave.<br />Design: Cross-sectional study by online questionnaire, with blood serology testing.<br />Setting: Three main school districts (Vancouver, Richmond and Delta) in the Vancouver metropolitan area.<br />Participants: Active school staff enrolled from January to April 2022, with serology testing between 27 January and 8 April 2022. Seroprevalence estimates were compared with data obtained from Canadian blood donors weighted over the same sampling period, age, sex and postal code distribution.<br />Primary and Secondary Outcomes: SARS-CoV-2 nucleocapsid antibody testing results adjusted for test sensitivity and specificity, and regional variation across school districts using Bayesian models.<br />Results: Of 1850 school staff enrolled, 65.8% (1214/1845) reported close contact with a COVID-19 case outside the household. Of those close contacts, 51.5% (625/1214) were a student and 54.9% (666/1214) were a coworker. Cumulative incidence of COVID-19 positive testing by self-reported nucleic acid or rapid antigen testing since the beginning of the pandemic was 15.8% (291/1845). In a representative sample of 1620 school staff who completed serology testing (87.6%), the adjusted seroprevalence was 26.5% (95% CrI 23.9% to 29.3%), compared with 32.4% (95% CrI 30.6% to 34.5%) among 7164 blood donors.<br />Conclusion: Despite frequent COVID-19 exposures reported, SARS-CoV-2 seroprevalence among school staff in this setting remained no greater than the community reference group. Results are consistent with the premise that many infections were acquired outside the school setting, even with Omicron.<br />Competing Interests: Competing interests: CO'R is an employee of the Vancouver School District, but the latter was not involved in the design, analysis, interpretation of data or the drafting of this manuscript. LifeLabs played no role in the study other than providing a service for the collection of blood samples.<br /> (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Details

Language :
English
ISSN :
2044-6055
Volume :
13
Issue :
6
Database :
MEDLINE
Journal :
BMJ open
Publication Type :
Academic Journal
Accession number :
37308276
Full Text :
https://doi.org/10.1136/bmjopen-2022-071228