A staff member at Beaver Brae Secondary School in Kenora has tested positive for COVID-19.
The Keewatin-Patricia District School Board says all contacts of the case are being called and given instructions by public health officials.
The board is also working with the health unit to make sure all potential risks are minimized.
Staff and students not contacted are considered to be at no additional risk and can continue to attend school as usual.
Three positive cases have been reported at two Dryden schools in the span of a week but officials stress there has been no school exposure at Dryden High or New Prospect.
All students and staff should continue to use the Ontario School Screening Tool daily before attending school.
As a reminder for families, should your child(ren) develop any symptom(s) consistent with COVID-19, you should not send them to school and should contact the local assessment centre to make arrangements for testing.