NRPH confirmed 85 cases between Saturday and Monday in Niagara in another large jump in cases across the region.
26 cases were confirmed on Saturday, 39 on Sunday, and another 20 on Monday, bringing the total active cases to 242 as of noon, Monday.
Regional data shows three new cases were confirmed in Thorold over the weekend.
112 town residents have tested positive in total.
The death toll remained at 87, which is unchanged from last week.
There are 14 active outbreaks, of which 6 are found in long-term care or health care facilities.
Ages 20-39 is the dominating age group in Niagara in which the virus has been found.
Ontario update
Public Health Ontario reported 1,925 new cases of COVID-19 today, which is one more than yesterday's report of 1,924.
For the last three days, the province has reported a record number of cases per day. On Saturday, the province reported 1,859 cases.
Ontario's public health agency also confirmed 26 deaths in today's report. The deaths include one person between 40 and 59 years old, ten people between 60 and 79 years old, and 15 people over the age of 80. Thirteen of the people whose deaths were reported today were residents of long-term care homes.
Since yesterday's update, 66 people have been hospitalized with COVID-19 and five people have been admitted to intensive care units with the disease.
Of the 1,925 new cases reported today, 512 are from Peel, 167 are from York Region, 601 are from Toronto, and 133 are from Durham Region.
Public Health Ontario has confirmed 138 new school-related cases of COVID-19 since Friday, including 109 student cases and 29 staff cases. There have been 1,526 school-related cases reported in the last 14 days and 5,402 school related cases reported in total.
There are 803 schools with one or more COVID cases reported, and 10 schools in the province are closed because of COVID-19 cases.
There are 16,034 lab-confirmed active cases of COVID-19 in Ontario currently. There are 725 COVID-19 patients hospitalized with 213 of those patients in intensive care units and 121 COVID patients on ventilators.
Since last report, provincial labs have processed 45,283 COVID-19 tests producing a four per cent positivity rate.
To date, the province has reported 129,234 lab-confirmed cases of COVID-19, 109,402 recoveries, and 3,789 deaths.
The cumulative incidence rate for Ontario is 869.4 cases of COVID-19 per 100,000 people. The weekly incidence rate between Nov. 27 and Dec. 3 in Ontario is 81.3 cases per 100,000 people in seven days, which is an increase of 13.5 per cent compared to the week of Nov. 21 to 27.
