TORONTO — A region west of Toronto comprising roughly three per cent of Ontario's population currently accounts for nearly half of the province's new COVID-19 diagnoses, Premier Doug Ford said Friday as he raised the prospect of rolling back reopening measures to contain the situation.

The latest figures showed Peel Region, a long-standing hotspot for the novel coronavirus, was home to 72 of the 148 new COVID-19 cases reported provincewide.

Ford characterized the data as concerning, particularly in recent days. While new cases have consistently stood at five or fewer in the majority of Ontario's public health units, Peel, Toronto and Ottawa have consistently registered double-digit, upward-trending numbers over the past few weeks.

Ford said something is clearly "broken" in the region that includes bedroom communities such as Mississauga and Brampton, calling on residents to heed public health advice and hinting the government was prepared to take action if case levels don't come down.

"We won't hesitate to again shut it down," Ford said at his daily pandemic briefing. "We're seeing a slow creep, so folks, just follow the protocols."

The province's latest COVID-19 figures, which included no new deaths, showed 41 of the latest cases came from Toronto while 13 surfaced in Ottawa. The rest of Ontario's public health units registered five cases or fewer, with 12 reporting none at all.

The new diagnoses bring the province's total number of confirmed cases to 42,834.

The slow but steady increase in numbers comes days before the bulk of Ontario students prepare to head back to class under conditions that have generated reactions from scorn to alarm among parents and educators alike.

The province's decision not to impose class size caps on elementary school students has drawn widespread criticism from those who argue crowded classrooms will make it impossible to observe the physical distancing measures widely touted by public health officials.

Other critiques centred on the amount of money the province was willing to spend on back-to-school plans, as well as failure to provide clear guidance to school boards or establish clear safety protocols to protect bus drivers.

The province has pledged $309 million towards reopening schools in the wake of the pandemic and permitted boards to access $500 million of their own reserves in order to fund the return to class. The federal government has since kicked in $381 million in immediate back-to-school aid with the promise of more cash to come by December.

The plan for reopening schools, along with stubborn infection rates and aspects of the provincial economic revival strategy currently in its third phase, have drawn calls for Ontario's top doctor to step down before an anticipated second wave of the virus.

The Registered Nurse's Association of Ontario was among the most recent to call for Dr. David Williams to resign or be replaced as Chief Medical Officer of Health.

But Ford dismissed such calls on Friday, vehemently defending the man whose advice he has said forms the core of Ontario's pandemic response.

"Dr. Williams, in my opinion, is an absolute champion," he said. "... He's not the type of person to say, 'this is what we're deciding, it's my way or the highway.' He talks to all the health experts around the country. I'll stand beside Dr. Williams any day, any pandemic."

Ford cautioned Ontario residents, particularly those in regions still struggling with elevated COVID-19 numbers, to avoid large social gatherings and continue wearing masks, particularly during the upcoming Labour Day weekend.

This report by The Canadian Press was first published Sept. 4, 2020.

Michelle McQuigge, The Canadian Press