COVID-19 infections are on the rise again in Ontario after the province reported a drop in new cases on Sunday.

Ontario is reporting 615 new COVID-19 cases today, up from the 566 recorded one day earlier but down from 653 on Saturday.

The seven-day rolling average of new cases now stands at 612.

Ontario processed more than 38,000 tests over the past 24 hours, bringing the case positivity rate to 1.6 per cent.

The testing backlog now stands at about 68,000 specimens, down from 79,000 on Sunday.

More than 4,000,000 tests have now been completed in Ontario since the virus reached the province in late January.

The total number of deaths in the province rose to 2,980 today after five new virus-related fatalities were confirmed in the past 24 hours.

Two of the latest deaths are residents of long-term care facilities.

COVID-19 hospitalizations continue to climb in Ontario with 176 patients receiving care at Ontario hospitals, up from 169 on Sunday and 155 on Saturday.

The province notes that this figure does not include data from 35 hospitals, which did not submit information in time to be included in today's report.

The number of patients in intensive care now stands at 43.

About 58 per cent of all new cases involve people under the age of 40, a number that has steadily declined in the last few weeks.

In mid-September, that demographic accounted for about 70 per cent of all new cases.

"We are seeing an uptick in other age groups, including some among are over 60s, 70s, and 80s," Ontario's Chief Medical Officer of Health Dr. David Williams said on Monday. "That is a concerning early indicator that needs to be observed."

The number of active cases now stands at 5,470, up from 4,564 one week ago.

The province's latest epidemiological summary indicates that 289 new cases were reported in Toronto, 88 were in Peel Region, and 81 were in Ottawa.

The latest data comes just days after Toronto Public Health confirmed it has suspended contact tracing for some cases due to the spike in infections in the city.

Contact tracing of close contacts of confirmed cases outside of outbreaks in congregate settings has been halted temporarily.

Pause on contact tracing in Toronto 'very troubling'

Infectious disease specialist Isaac Bogoch told CP24 on Monday that the situation with contact tracing in Toronto is concerning.

"From the very beginning we have heard this mantra— test, trace, isolate, and support," Bogoch said.

"It is obviously very troubling when the number of cases is so high that tracing is essentially overwhelmed and is essentially meaningless if it can't be conducted in a meaningful (amount of) time because of the delays in diagnostic tests coming through and the turnaround of the tests plus the volume of cases that need to be contact traced."

The province has said it will be providing about 200 additional staff members to Toronto Public Health to help deal with the rapid rise of COVID-19 cases.

Contact tracing and testing were among the topics discussed in a call between Prime Minister Justin Trudeau and Mayor John Tory on Monday.

"I imagine that this program will likely be re-initiated when there are resources that can facilitate it. It certainly is concerning when we hear about that especially with the volume of cases rising in Toronto," Bogoch said.

Williams said one of the issues is that a number of positive cases have far too many close contacts to follow up with.

"We still get some people say that… within the last number of days… ‘I think I’ve had somewhere between 200 to 300 contacts.’ That’s surprising and perplexing," Williams said. 

"If you did your proper methods of social distancing, you shouldn’t have that many to talk about. That’s why we are asking you to do all that, and to follow that, so that when public health is trying to follow up, they don’t have to follow 200, 300, 400, 500 people...As a result, some places like Toronto Public Health are overwhelmed with the amount of contacts per case."

New cases in the GTA:

Toronto: 289

Peel Region: 88

York Region: 47

Halton Region: 26

Durham Region: 10