TORONTO - Children in Ontario's four COVID-19 hot spots should not go trick-or-treating this Halloween, the province's top doctor said Monday as cases continued to increase in those regions.

Dr. David Williams, the province's chief medical officer of health, said the high transmission of the virus in Toronto, Ottawa, Peel Region and York Region had prompted his recommendation.

“Traditional door-to-door trick-or-treating is not recommended and people should consider alternative ways to celebrate,” Williams said in a statement, adding that it was also important that families not travel outside their neighbourhods to celebrate Halloween.

Williams' advice came as Ontario reported 704 new cases of COVID-19 and four new deaths due to the virus.

The largest daily gains came in the four hot spots, with 244 cases in Toronto, 168 in Peel Region, 103 in York Region and 51 in Ottawa.

Williams also recommended that children in other regions of the province only trick-or-treat with members of their household.

“I would also like to remind everyone that we are in a second wave of COVID-19,” he said. “There have been increases in cases in many areas across the province, and the percentage of people tested who get a positive result is going up.”

But at least one infectious disease expert said the recommendation didn't sit right with him.

The goal should be to find ways to do things safely rather than cancel Halloween activities, Dr. Isaac Bogoch said.

“Halloween shouldn't be too tough to do safely,” he wrote on Twitter. “Outside, wearing masks, restricted to family units, distant from others - is about as low risk as it gets.”

NDP Leader Andrea Horwath said the province's message on Halloween is confusing when its contrasted with its policy on schools.

“We send kids to school 30 to a classroom,” she said. “We put kids on buses, 70 to a bus, inside, indoors, in cramped circumstances ... but somehow a door-knocking outdoor activity is more dangerous than that. I don't blame parents if they're extremely confused.”

Williams' Halloween guidance came as stricter measures to curb the spread of COVID-19 took effect in York Region.

The province already imposed the same measures on Toronto, Peel Region and Ottawa earlier this month.

Indoor service in restaurants is prohibited, gyms and movie theatres are closed and public gatherings can be no larger than 10 people indoors or 25 people outdoors.

Meanwhile, the province reported 74 new COVID-19 cases related to schools on Monday, including at least 48 among students. Those bring the number of schools with a reported case to 483 out of Ontario's 4,828 publicly funded schools

Monday's figures bring the total number of COVID-19 cases in Ontario to 65,075