Four more COVID-19 cases have been detected at schools in Woodstock and Aylmer.
The Thames Valley District School Board confirmed the cases Wednesday night at Huron Park Secondary and Springbank Public in Woodstock and McGregor Public in Aylmer.
Huron Park and McGregor Public had one case each, while Springbank Public had two additional cases on top of those reported on Monday.
So far this week, there have been cases of the virus reported at 15 Thames Valley schools. There are currently 56 active cases at 39 schools within the board. That is the highest number of active cases at Thames Valley schools since in-person learning resumed in September.
Only those who have been in close contact with the infected individuals are being advised to isolate at home.
All schools remain open.
"Thames Valley is following all health and safety protocols recommended by both the local public health unit and the Ministry of Education, and schools remain safe places to attend," the board said in a statement.