Goldfarb DM, Mâsse LC, Watts AW, Hutchison SM, Muttucomaroe L, Bosman ES, Barakauskas VE, Choi A, Dhillon N, Irvine MA, Reicherz F, O’Reilly C, Sediqi S, Xu RY, Razzaghian HR, Sadarangani M, Coombs D, O’Brien SF, Lavoie PM. SARS-CoV-2 seroprevalence among Vancouver public school staff in British Columbia, Canada: a cross-sectional study. BMJ Open. 2022 Apr 5. doi: 10.1136/bmjopen-2021-057846.
The results and/or conclusions contained in the research do not necessarily reflect the views of all CITF members.
In a study now published in BMJ Open, Drs. Pascal Lavoie and Louise Mâsse and their team at the University of British Columbia found that school staff were not at increased risk of SARS-CoV-2 infection at school, compared to the local community, in the 2020-2021 academic school year. The authors attribute this, in part, to the appropriate public health measures being in place. This study predates the emergence of most variants of concern in Canada, including Delta and Omicron. Participants in the serosurvey were employed with the Vancouver School Board, which maintained in-person schooling during the period in question.
- Of the 1,556 participants tested (92.1% of total cohort of 1,689), 35 showed evidence of a past infection with SARS-CoV-2. This resulting rate of seropositivity of 2.3% was in line with the rate found in the reference group (people from the community not working in schools with a similar profile of age, sex, and area of residence).
- Although as many as 278 school staff reported a close contact with a COVID-19 case, only 24 (incidence rate of 1.4%) tested positive for the virus through PCR testing, of which five (21%) believed they had acquired the infection at school.
- Seven of the 24 (29%) who tested positive reported a close contact with a friend or family member with COVID-19 and one (4%) reported close contact with both a co-worker and a family member with COVID-19. The remaining 11 (46%) were not aware of any close contact with a COVID-19 case or the source of infection.
The study enrolled 1,689 participants between February and May 2021 who completed a questionnaire and provided a dried blood spot sample. Many participants worked in classrooms (78.2%) and, of these, most worked exclusively in elementary schools (64%) or secondary schools (28%), with a few working with several grade levels or at the school board office (8.3%).
The study team concluded that despite a high perception of potential exposure in school settings, the percentage of infected individuals within Vancouver public schools was similar to that of the local community at the time of the study.