Another person linked to a school in the region has tested positive for COVID-19.

The Thames Valley District School Board (TVDSB) said Southwestern Public Health has identified a case at Mitchell Hepburn Public School in St. Thomas.

This is the second case the region has seen that involves someone attending a school. Last week, the first confirmed case was a student at H.B. Beal Secondary School in London. There were also two other cases involving students enrolled in remote learning.

The health unit is not disclosing if the case involves a student or a staff member, citing privacy reasons. While the province does track COVID-19 cases at schools and specifies the number of students and staff infected, as of Tuesday afternoon the case had not been uploaded to the public database.

Based on the information currently available, Dr. Joyce Lock, the medical officer of health with Southwestern Public Health, told CBC News the individual didn't catch COVID-19 at Mitchell Hepburn Public School.

"We have no other confirmed or probable cases, but the [individual] was considered infectious on one of the days [they] attended the school," said Lock.

Lock said close contacts of the confirmed case have been contacted and will be self-isolating for 14 days.

"The idea is to keep the school case from spreading any further by having people who might have caught it stay at home, watch for symptoms, self-isolate and go and get tested if any symptoms develop," Lock added.

She said the risk of exposure is low for those in the school who were not in direct contact with the person who has tested positive.

"Thames Valley is following all of the health and safety protocols recommended by public health and the Ministry of Education," Mark Fisher, the education director with TVDSB, said in a media release. "Mitchell Hepburn remains a safe place to attend school."

TVDSB said staff and parents have been notified of the case. The school will remain open and buses will continue to run.

If you are not contacted by the health unit, then your child is not considered to be at risk, the board said.

All confirmed cases within the TVDSB can be found on their website.

Last Friday, the health unit identified a probable case at St. Thomas Community Christian School and launched an investigation to identify how the person got infected. As of Tuesday evening, the case had not been added to the Ministry of Health's database.

"Whether you're a probable case or a case, we treat them exactly the same way," Dr. Lock said, adding that the person is now isolating and that the health unit has reached out to all of the person's close contacts.