KITCHENER -- A COVID-19 outbreak has been declared in a cohort at Hillcrest Public School in Cambridge. The Waterloo Region District School Board announced the outbreak on Thursday after a staff member there had tested positive for the disease. According to a news release, the staff member was in the same cohort as a student case that was reported on Dec. 13. That student was last in the building on Dec. 7, the school board said. Two other staff members have been identified and asked to self-isolate, but so far no other Hillcrest Public School students have had to do so. Since Sunday, there have been 21 cases of COVID-19 reported in the region's public school board. You can track every local case in publicly funded schools using our online COVID-19 tracker.