The Greater Essex County District School Board reported six new cases at its schools on Friday.
A staff member at Essex District Secondary School tested positive.
Students at Ford City, Parkview, McWilliam and Roseland Public Schools have also been diagnosed with the virus, along with one student at Kennedy High School.
The school board reports 16 cases in total.
It does not make public how many classes or cohorts have been dismissed, but all the parents of impacted students have been notified.