The risk of staff acquiring SARS-CoV-2 in schools is no greater than their risk of acquiring the virus in day-to-day life in the community, according to a new study led by researchers from UBC, BC Children’s Hospital, and Vancouver Coastal Health. The findings have been published as a pre-print ahead of peer review.
“These findings show that, with appropriate mitigation strategies in place, in-person schooling is not associated with significantly increased risk of SARS-CoV-2 transmission for classroom-based staff compared to members of the general population,” says the study’s principal investigator Dr. Pascal Lavoie, associate professor in the faculty of medicine’s department of pediatrics and an investigator at BC Children’s Hospital.
Researchers tested Vancouver School District staff during the 2020-2021 school year for SARS-CoV-2 antibodies – a sign of prior infection – to determine how many had been infected with the virus, whether or not they had felt symptoms.
Of the 1,556 school staff who had their blood sample tested, 2.3 per cent tested positive for antibodies. This percentage was similar to the number of infections in a reference group of blood donors matched by age, sex and area of residence. The results confirm the low prevalence of SARS-CoV-2 infection among staff in the school setting.
“Even when we account for asymptomatic infection using sensitive blood tests, the risk of SARS-CoV-2 being transmitted in schools overall remains very low,” says study co-investigator and the article’s lead author Dr. David Goldfarb, clinical associate professor in the faculty of medicine’s department of pathology and laboratory medicine andinvestigator and a medical microbiologist at BC Children’s Hospital.
Of the 1,689 school staff surveyed, 278 reported close contact with a student or co-worker who was a COVID-19 case, but only five staff who were infected with SARS-CoV-2 believed they likely acquired the virus in the school setting. Another seven staff infected with SARS-CoV-2 reported a close contact with a friend or family member as the main source of contact.
“The results suggest that only a few teachers and school staff contracted SARS-CoV-2, and most assume that they did not contract it at school and thought they caught it from friends or family,” says Dr. Lavoie.
The study also reports on positive viral polymerase chain reaction (PCR) tests in students and staff—the number of people who were tested and were found to be infected with SARS-CoV-2 at the time they were tested. Within the Vancouver School District, 0.98 per cent of the 47,280 students, and 1.3 per cent of the 7,071 staff attending the Vancouver School District received a diagnosis of COVID-19 between the start of the pandemic and March 4, 2021. In this study, school staff reported consistent rates of positive viral tests which are similar to the Vancouver School District—1.3 per cent.
“We hope our findings will help inform school opening and closure policies moving forward,” says co-lead researcher Dr. Louise Mâsse, professor in the faculty of medicine’s School of Population and Public Health and an investigator at BC Children’s Hospital.
“We know how important in-person schooling is for our students, not only for learning, but also for their social, mental, and physical well-being,” says Suzanne Hoffman, superintendent of schools for the Vancouver School District. “These results reaffirm that with the protocols we have in place, schools are safe places to teach and learn.”
“This study highlights that COVID-19 in a school setting typically mirrors transmission from family and community contacts. As more and more Canadians are vaccinated, this will be expected to further reduce family—and community—based COVID-19 transmission,” says Dr. Mel Krajden, professor of pathology and laboratory medicine at UBC’s faculty of medicine and COVID-19 Immunity Task Force leadership group member. The results of this study are very timely as provincial governments across the country are planning and announcing back-to-school scenarios for the next school year. This and the results of other Task Force studies will help guide an evidence-based return to in-person teaching.”
This study was funded by the Government of Canada through its COVID-19 Immunity Task Force (CITF).
The research team was led by Dr. Lavoie and Dr. Mâsse, and also includes Dr. Goldfarb, Dr. Vilte Barakauskas, Dr. Julie Bettinger, Dr Tim Oberlander, Dr. Mike Irvine and Dr. Manish Sadarangani from UBC and BC Children’s Hospital, as well as Dr. Daniel Coombs from UBC’s department of mathematics, Dr. Eva Oberle and Dr. Anne Gadermann from UBC’s school of population and public health, Dr. Agatha Jassem from BCCDC and Dr. Alex Choi, VCH.
A version of this story was originally published by CITF.