LONDON, ONT. -- School and health officials say classrooms remain safe, even with active COVID-19 cases in 30 London-area schools.

According to the Thames Valley District School Board (TVDSB) website, there are currently 26 schools in the region with at least one or more active COVID-19 cases, but only a small fraction have led to outbreaks.

Middlesex-London Health Unit (MLHU) Medical Officer of Health Dr. Chris Mackie says the region has not really seen much spread in schools.

"The vast majority of cases diagnosed in school were acquired at home. We've seen very little transmission within schools, really only a handful of cases among the tens of thousands of students that have been in school for the last two months, so schools are not a place of high transmission in this area."

London District Catholic School Board (LDCSB) Director of Education Linda Staudt says, "Our schools are safe, we are able to keep them in cohorts and they are masked now when they're inside and outside...We don’t want to interrupt the learning so we definitely want the students to be with us in school."

The Catholic board is reporting just four schools with active cases.

Mackie adds that closing schools, as is happening in some other regions in Ontario, brings with it its own risks in addition to disrupting education.

"If people can't stay home with their children, you know there's a risk that those children are going to be mingling in uncontrolled environments outside of their cohorts, and that actually potentially increases the spread of COVID."

In an interview with CTV News on Thursday, TVDSB’s Education Director Mark Fisher said until the board hears otherwise, schools will remain open.

Currently, there are active outbreaks at four London-area schools, with the most recent declared on Friday.

After a second positive COVID-19 case at Sir Frederick Banting Secondary School in London linked to a previous one at the school, an outbreak was declared there by the MLHU.

In a statement sent to parents and guardians, Dr. Alex Summers, the associate medical officer of health, said the outbreak did not mean the school was closing, but rather that there was evidence of transmission at the school between two or more cases.

Summers added that it appears this new case was not at school while infectious, therefore there have been no additional close contacts identified.

Meanwhile, the LDCSB has temporarily closed Holy Rosary Catholic Elementary School due to staffing concerns related to COVID-19.

The elementary school will be closed for four days, after three cases of COVID-19 were reported. Two-thirds of staff and half of students are in isolation.

On Thursday, Ontario Education Minister Stephen Lecce released a statement reassuring parents and students that schools will continue to be open for in-class instruction.

The April Break will also proceed as planned and new protocols will be introduced to ensure students and staff return to class safely following the break. Details on those protocols are expected from the province soon.

Students are expected to be back in class on April 6, with the spring break to run from April 12 to 16.

- With files from CTV's Reta Ismail and Daryl Newcombe