BARRIE, ONT. -- The Simcoe Muskoka District Health Unit is concerned with what it calls a troubling trend.

"We've had a growth in the pandemic," Medical Officer of Health Dr. Charles Gardner said. "The most significant driver for that would be people socializing, among family members, larger groups, potentially beyond their social circle of 10 people," he added.

In the past month, COVID-19 cases had been on a downward trend, but now the health unit said they are on the rise.

An outbreak was also declared at Mill Creek Care Centre in Barrie, where a staff member tested positive for the virus.

Residents at the long-term care home on Hurst Drive are now undergoing testing.

On Tuesday, the health unit confirmed a Barrie girl under the age of 17 also tested positive for COVID-19. It's yet another alarming discovery as the health unit barrels ahead with back to school preparations.

Yesterday, Education Minister Stephen Lecce said that local health units could delay schools' open dates if necessary.

"We all just want to ensure we follow the public health advice and give the school board those additional few days to get it right," Lecce stated.

Dr. Gardner said the health unit had not made that recommendation or request at this time.

The health unit's top doc admitted contact tracing has become extremely difficult as more people open up their bubbles and venture out more places. He warns that it's important to remain in your 10 person bubble.