Understanding COVID-19 cases among school-aged children and school staff in early 2021.
Surrey schools review - January to June 2021
Fraser Health Public Health examined cases of COVID-19 reported between January and June 2021 to better understand the extent and nature of in-school transmission of the virus in Surrey schools.
The review found that, overall, 90 per cent of school-associated COVID-19 cases in Surrey originated in households or the community, not in schools. Other key highlights include:
- Between January and June 2021, staff accounted for 11 per cent of the cases and students 89 per cent, which is expected as students make up the majority of the school population.
- Approximately three per cent of the overall school population in Surrey was reported to have COVID-19 during the study period.
- Of the small minority of the school population that did get COVID-19, most of them acquired it at home or in the community and had limited spread within schools.
- Trends in school cases tend to match those in the community. Cases increased in late February and peaked in mid-to-late April. School-associated COVID-19 cases among ages 18 and over decreased with the availability of vaccine.
- Once staff immunization campaigns started, there was a noticeable drop in cases among those 18 and older. Student cases declined as cases fell in the community, largely reflecting increasing vaccination coverage over time.
- Variants of concern were more common after spring break, but did not impact the size of clusters in schools. A cluster is defined as two or more cases within a 14 day period at a given school. The Delta variant was not yet prevalent in the community during the review period, but will be monitored by Fraser Health Public Health as school resumes in September.
The information garnered from the review will help to guide public health measures in the Fraser Health region for the upcoming school year.
COVID-19 and Surrey schools data
VIew Fraser Health’s COVID-19 Surrey school cluster and transmission data analysis, January to June, 2021
Region-wide review - January to March 2021
Fraser Health undertook an analysis of COVID-19 cases among school-aged children and school staff from January 1 to March 7, 2021 to better understand the extent and nature of in-school transmission of the virus.
These data were used, alongside a similar analysis completed by Vancouver Coastal Health in late 2020, as part of the provincial discussion over whether or not to close schools, and to inform prioritization of school staff for vaccination.
Our data demonstrated that during the nine week period of analysis that <1 per cent of the approximately 315,000 staff and students in the Fraser region had contracted COVID-19. Other key highlights include:
- Of these 2049 confirmed cases, the majority (87 per cent) were acquired outside of school.
- Of the 2049 confirmed cases, just under 20 per cent were associated with a confirmed school cluster or outbreak.
- These confirmed clusters, and one outbreak, were distributed among 116 of the nearly 640 K-12 schools in the region.
- Of the 267 cases (13 per cent of total school cases) believed to have acquired COVID in school, 88 (4.3 per cent of total school cases) led to household/community transmission, and mostly within the household.
- While this did represent the early days of variant of concern circulation in our region, in-school transmission represents a small fraction of the COVID-19 cases among school staff and school-aged children.
- Notification letters are provided to the school community when there has been a case at a school during the case’s infectious period.
- The results of our analysis demonstrate that in-school transmission represents only a fraction of cases associated with schools and, as such, the notification letters issued over the nine week period were not a direct correlation of the degree of in-school transmission.
Fraser Health will be conducting additional analyses of school-associated COVID-19 cases since March 7 to review the impact of factors such as variants and immunization efforts.
COVID-19 and region-wide schools data
See Fraser Health’s COVID-19 school cluster and transmission data analysis, January 1 to March 7, 2021