Ontario is reporting nearly 1,200 new cases of COVID-19 today as the rolling seven-day average of new infections continues to rise in the province.

Provincial health officials logged 1,185 new cases of the disease caused by the novel coronavirus today and another six deaths.

Today's tally is down from the 1,631 new infections reported on Monday, although the province said yesterday's case count was inflated due to a data reporting issue. The Ministry of Health did not disclose how many of Monday's cases should have been included in previous totals.

The rolling seven-day average of new cases now stands at 1,187, up from 1,098 last week.

With 33,300 tests completed on Monday, today's test positivity rate is now 3.7 per cent, a notable jump from 2.9 per cent one week ago.

Active cases are also on the rise in the province. There are now 11,223 active lab-confirmed infections of COVID-19 in Ontario, up from 10,546 seven days ago.

According to the province, nearly 10 per cent of all active cases today involve primary and secondary school students.

For the third day in a row, none of the six virus-related deaths confirmed in Ontario today involve residents of long-term care. Despite the uptick in new cases over the past week, the average number of virus-related deaths recorded per day has dropped to 12 today, down from 17 last Tuesday.

Of the new cases reported today, 343 are in Toronto, 235 are in Peel Region, and 105 are in York Region.

Virus-related hospitalizations are continuing to climb along with intensive care admissions. The number of people with COVID-19 who are receiving treatment in hospital is now 689, up from 677 last week. The province is reporting that there are now 290 patients with COVID-19 in the ICU, up from 284 last Tuesday.

Numbers released by individual local public health units indicate that there are now 834 COVID-19 patients in hospital.

Dr. Irfan Dhalla, a University of Toronto medical professor and vice-president at Unity Health Toronto, tweeted Tuesday that the number of patients with COVID-19 who are currently in the ICU is actually 344, an increase of 27 patients over the past 24 hours.

Speaking about the need to roll out vaccines to the most vulnerable groups as quickly as possible, Dr. Michael Warner, the medical director of critical care at Michael Garron Hospital, told CP24 on Tuesday that he believes a third wave of the pandemic has already arrived in Ontario.

"Wave three, I believe, is upon us. ICU numbers are increased today. Case numbers are rising and a vaccination also buys people more freedom," Warner said.

"So we need to make sure we prioritize the people who are most likely to get sick and die from COVID within Phase 2 (of the vaccination program) and make sure the people who could get COVID but almost certainly are going to survive are toward the end of the line so that we save the most lives."

An estimated 943,533 doses of a COVID-19 vaccine have been administered in Ontario to date. Many municipalities have begun inoculating their oldest residents and on Monday, the City of Toronto confirmed that it will open three mass immunization clinics next week to begin vaccinating people in the community who are over the age of 80.

The province said another 29 cases of the more transmissible B.1.1.7 variant, which was first discovered in the United Kingdom, have been confirmed through full genome sequencing, bringing the total number of cases of the variant in Ontario to 908. Thousands of other cases in the province have screened positive for a variant but have not yet been officially confirmed as one of the three main variants of concern circulating in Ontario. Officials have estimated that approximately 40 per cent of all new infections in Ontario are variant cases.

The numbers used in this story are found in the Ontario Ministry of Health's COVID-19 Daily Epidemiologic Summary. The number of cases for any city or region may differ slightly from what is reported by the province, because local units report figures at different times.