For the third time in a week, a COVID-19 outbreak has been declared at a school in the region, according to the Waterloo Region District School Board.
On Thursday night, the board announced the latest outbreak at Elmira District Secondary School.
It says a student in a cohort that was asked to isolate last week has tested positive for the coronavirus.
The WRDSB says some additional students have been asked to isolate as a result of the new positive test but no other staff members have been affected.
COVID-19 outbreaks were also declared at Clemens Mill Public School on Wednesday and William G. Davis last Saturday. Both schools are located in Cambridge.
There have now been 12 outbreaks at schools in Waterloo Region since Labour Day weekend with five currently considered active.
The other two are at Blessed Sacrament and St. Bernadette in Kitchener, which began on Nov. 25 and Nov. 17 respectively.