TORONTO -- COVID-19 outbreaks have been declared at two Toronto elementary schools just one week after students returned to the classroom.

Toronto Public Health says that it has declared outbreaks at both Alvin Curling Public School in Scarborough and King George Junior Public School in Runnymede after determining that at least two cases of the disease caused by the novel coronavirus at each school were "linked."

At this point, both schools remain open for in-person learning.

"We're carefully investigating and following our process of working with our school community to notify close contacts and ask them to stay home, monitor for symptoms and get tested," Toronto Public Health said in a series of messages posted to Twitter on Thursday afternoon. "This isn't unexpected given COVID-19 continues to circulate in our city and how transmissible the Delta variant is."

There are currently three active cases among students and one active case among staff at Alvin Curling Public School. At King George Junior Public School, there are two active cases among students.

ACTIVE CASES SURPASS 500

The outbreaks are the first to be formally declared at Toronto schools since the resumption of classes last week.

Earlier on Thursday, Ontario’s publicly funded school boards reported more than 100 new COVID-19 cases among staff and students as the total number of active infections surpassed 500.

The Ministry of Education says that there were 109 new school-related cases of the disease caused by the novel coronavirus confirmed over the last 24 hours.

That includes 98 student cases, eight staff cases and three unspecified cases.

The latest tally is down from the 168 new cases reported one day prior but is otherwise the highest number of new cases reported in any single 24-hour period so far this school year.

In fact, since students returned to the classroom in most boards last week there has been a steady rise in the number of positive cases among staff and students, though it is unclear whether that could be a product of increased testing volumes and policies requiring that some symptomatic students test negative before returning to the classroom.

Ontario’s labs processed more than 34,000 tests on Wednesday, which was the highest number in any single 24-hour period since early June. It also processed more than 33,000 tests on Tuesday, also a multi-month high.

““Of course there are cases that are in schools. We know that is going to happen. The burden of cases introduced into schools is going to be reflective of the burden in the community and sadly some cases are going to be transmitted in schools but let’s put this into perspective: there are over two million students in schools and we are talking about a few hundred cases,” infectious disease specialist Dr. Isaac Bogoch told CP24 on Thursday morning as he discussed the latest numbers. “Let’s talk about making schools safer, let’s talk about reducing the risk of bringing this into schools, let’s talk about lowering community transmission to reduce that risk, let’s talk about steps we can take to create safer schools now. We should not have to pull the plug on schools this year.”

ONLY ONE SCHOOL HAS BEEN CLOSED

The 109 new school-related cases reported on Thursday accounted for roughly 12.6 per cent of Ontario’s overall caseload, which is an increase from the previous day when they accounted for roughly eight per cent of cases.

The ministry says that there are now cases at 348 schools but only one of them – St. Joseph’s High School in Windsor – has been closed due to a COVID-19 outbreak.

However, there are other dozens of classes at other schools that have been switched to remote learning as a precaution following the detection of positive cases.

Bogoch conceded that the numbers “are not good” while speaking with CP24 but he said that the school year is “five-minutes-old” and suggested that it is “premature” to make any conclusions at this time, especially around the viability of in-person learning amid the fourth wave of the pandemic.

“Look it is an issue but it way too soon to talk about pulling the plug on schools,” he said.

Four of the new cases reported on Thursday were in the Toronto District School Board while three were in the Toronto Catholic District School Board.

The Peel District School Board reported a total of 14 confirmed cases and 13 closed classrooms.