KITCHENER -- A Catholic elementary school in Cambridge will reopen Thursday morning after a temporary closure over a positive COVID-19 case.

According to a letter issued by St. Gregory Catholic Elementary School, one member of the school tested positive for COVID-19.

The Waterloo Catholic District School Board website shows one staff member tested positive on Feb. 20.

In a statement to CTV News, the school board confirmed that the elementary school would reopen on Thursday. However, two other schools remain closed due to COVID-19, one in Kitchener and the other in Brantford.

In the letter announcing the initial closure at St. Gregory, officials said that high-risk contacts have been contacted and asked to isolate.

"The number of people currently being assessed as potential high-risk contacts is such that we do not anticipate having enough staff to safely deliver program at St. Gregory to begin the week (despite the fact that it is only one case at the current time)," the letter read in part.

While those contacts are being assessed, the school board has decided to close the school to in-person learning instead "out of an abundance of caution."

In an email, Director of Education Loretta Notten said that the decision was made because of how small the school is.

"Because it is a small school the positive case had contact with a number of staff, impacting four of six classes," she said. "Thus the decision was pretty simple. We could not safely staff the school."

She noted that the case is actually a "probable case" that public health officials are treating as a positive case.

The letter from the school noted that "most classes" had some exposure to the positive case.

"We will have remote learning occurring throughout the closure, with teachers posting classwork for the day by 9:30a.m. in the morning," the letter noted.

"If there are any further updates we will certainly share them as soon as possible."

Officials with the school board said St. Gregory will be one of the schools on their targeted testing list during the first few weeks of testing. They need to test two schools per week in order to meet the province's requirement of testing five per cent of schools.

"I think that's what sort of happened here, because it's such a small school and the effects were felt widely in the school, the decision was made to close the school until it's safe to return," said Patrick Etmanski, president of the Waterloo Region OECTA.

Etmanski said he's supportive of how the school is handling the situation.