The Catholic teachers' union is raising concerns about a COVID-19 outbreak in the Waterloo Catholic District School Board.

Public health officials are reporting four cases, but not identifying a school. It's part of a new provincial protocol during distance learning.

"Schools are opened for high-needs kids and the staff that work with them," said Patrick Etmanski, president of the local branch of the Ontario Elementary Catholic Teachers' Association.

The outbreak was reported on Saturday.

"We are only identifying the school board and number of cases associated with the outbreak," a statement from public health read in part.

A spokesperson for the school board said that, because of the low number of students who have returned so far, they didn't share the location of the outbreak to protect the identity of those infected.

Etmanski confirmed to CTV Kitchener that the outbreak is at St. John Catholic Elementary in Kitchener.

"Since Christmas, it's been like a complete dead zone in terms of information coming from them, in terms of cases with kids and staff," Etmanski said.

The spokesperson for the Catholic school board added that until the recent outbreak at St John CES, there have been no cases to report in the Catholic board in students or staff since the return to face-to-face learning.

The Ministry of Education also defended the decision not to identify the school.

"As there are only a limited number of students and staff currently physically in schools during the remote learning period, this creates unique privacy concerns for posting COVID-19 school cases on the Ontario public website at this time," the Ministry of Education said in a statement.

Etmanski said withholding information is concerning for teachers.

"I'm of the mind that it's about making people believe that the schools are safe and they'll do anything they can, by they I mean public health and the school boards, to increase the public's trust of the school," he said. "I respect the privacy of people that are involved, but ask the questions, share the information and let's get to the bottom of what the outbreak is, where it came from. Teachers want to help with that, because they want to feel safe coming into the building, too."

The ministry said tracking cases will resume across the province once students are back in the classroom.

The province will make an announcement about back-to-school dates on Wednesday.