Published Sunday, November 29, 2020 9:31PM EST
Last Updated Monday, November 30, 2020 5:03AM EST
In a letter sent to parents on Sunday, the principal of Thorncliffe Park Public School said Toronto Public Health (TPH) notified the school of the cases after 433 tests were completed on Thursday and Friday.
While the letter stated 20 cases were discovered, Toronto District School Board (TDSB) spokesperson Ryan Bird said in an e-mail to CP24 Sunday evening that 18 students and one staff member tested positive for COVID-19.
It brings the total number of active cases at the school to 21.
Bird said 14 classes have been asked to self-isolate for 14 days. The school located on Thorncliffe Park Drive, south of Overlea Boulevard, remains open.
Premier Doug Ford and Education Minister Stephen Lecce announced on Thursday that targeted voluntary asymptomatic testing will begin in schools in Toronto, York Region, Peel Region and Ottawa for the next four weeks in a bid to better track how the virus is spreading in and around schools.
“I know news of these additional cases will, understandably, be worrisome for families,” Principal Jeff Crane said in the letter.
“Since COVID-19 continues to spread in the community, finding additional cases in schools from broad testing is not unexpected at this time.”
Crane noted in the letter that the positivity rate within the school is at 4 per cent, which is lower than the 16 per cent positivity rate within the surrounding community.
“This means that there is currently a higher percentage of people who test positive for COVID-19 in the community compared to in this school setting,” he said.
“As a result, TPH does not believe it is necessary to close the school at this time.”
Crane said the school will be conducting a deep cleaning of the building before school starts on Monday.
Testing is expected to continue at the school on Monday.