EDMONTON -- A trio of COVID-19 cases at a public downtown Edmonton school was classified as an outbreak on Wednesday.

According to the public school division, Alberta Health Services identified two more cases at the Centre High campus on Sept. 15.

As a result, 128 more adult students and four staff need to isolate and be tested.

In total, three cases have been found at the school. Officials said the most recent cases were not contracted on campus.

The first was reported on Monday, and sent one employee and nearly three dozen adult learners home.

As well, 31 students and two employees of Eastglen School are at home after AHS confirmed one COVID-19 case there. The students are mostly in Grade 11, EPSB told CTV News Edmonton.

And, after a positive case at Lillian Osborne was confirmed Sept. 15, 58 students and two staff are no longer on campus. Those students are mostly in the graduating class.

EPSB protocol is to have students and staff who were in close contact with the sick individual self isolate for 14 days, monitor for symptoms, and be tested.

Only one additional Edmonton Catholic school reported a COVID-19 case the same day: St. Thomas Aquinas. Nineteen people were self isolating as a result. 

Altogether, the division had identified cases in 10 schools and 81 people at home becuase of possible transmission. 

CASES IN SCHOOLS IN THE GREATER METRO AREA

In the Elk Island public school district, two additional COVID-19 diagnoses were made at Bruderheim School and Fort Saskatchewan High. 

In addition to staff who were in contact with the students, one elementary class and two high school classes have been sent home to isolate. 

"A deep clean and disinfection was also implmented at each school," a division spokesperson said. 

Greater St. Albert Catholic Schools has counted two positive cases since the start of school: one at Morinville Community High School, and one in Richard S. Fowler Catholic Junior High School in St. Albert. 

Officials told CTV News Edmonton the Morinville student and close contacts have already returned to school, and no other cases were found at the campus. 

The RS Fowler student is still isolating, and those who were in close contact with them will return Sept. 24 or 25. 

St. Albert Public Schools has not reported any more cases, since two were identified at the SIGIS out-of-school-care facility in the first week of September.