After a steady increase in COVID-19 cases, Ontario is now reporting the lowest number of new cases of the virus since the end of March.

There were 287 new lab-confirmed cases of the virus reported on Monday, down from the 404 confirmed one day earlier.

This marks the lowest number of new cases since March 31, when 260 cases were reported in the province.

Over the past week, Ontario saw more than 400 new cases of the virus for five consecutive days, a spike which has been attributed to gatherings during Mother's Day weekend.

There were 460 new cases reported on Saturday, 412 new cases on Friday, 441 on Thursday, and 413 on Wednesday.

The rolling five-day average has steadily increased in the last week from 326 on May 18 to 426 on Monday.

According to the province’s epidemiological summary released Tuesday, which provides data from one day earlier, 21 more deaths were reported on Monday, bringing the total number of virus-related deaths to 2,123.

There have been a total of 26,191 cases of COVID-19 in Ontario to date and 19,958 of those are considered to be resolved.

The province continues to lag in testing numbers, with only 9,875 tests conducted on Monday and only 8,170 on Sunday.

Officials have previously indicated that they have the ability to turn around 20,000 tests per day.

Premier Doug Ford has promised to ramp up testing and over the weekend, he said anyone who feels they need to be tested for the virus will not be turned away from an assessment centre, regardless of symptoms.

Ford said the province will release its "detailed testing strategy" later this week and the strategy will include targeting certain sectors and COVID-19 "hot spots."

While the drop in new cases is encouraging, Ontario's Chief Medical Officer of Health Dr. David Williams told reporters on Monday that the province will be keeping a close eye on cases in the coming days to see how the Victoria Day weekend impacts new infections.

“The question is for the following weekend, Victoria Day weekend, are we going to see a similar bump again,” Williams said.

He said the effects of increased gathering, as measured in increased COVID-19 cases, is usually noticeable about seven to 10 days later.

“Therefore we would see a plateau and then a blip and then another plateau and then a blip,” Williams said. “That would be concerning because it could mean that people on the weekend have a sense that they can throw off all caution.”

Last week, the province allowed a number of additional businesses, including all retail stores with street entrances, to reopen to customers and the impact of that decision will be revealed later this week, Ontario Health Minister Christine Elliott said Monday.

"What we are going to see going in towards the end of this week will really be based more on the opening up of the economy that started up last week and that’s where both Dr. Williams and I will be very interested in the numbers," Elliott said.

"We hope that they will continue to go down but if they continue to increase that will be a time for us… to look at the situation, understand why the numbers are increasing and take action or don’t take action going forward."

Elliott said plans to expand the size of gatherings have been "pushed back" due to the spike in new cases.

"We had been discussing pools of people that could be together, the social cohorting and so on, but given what's happened with the numbers of people coming down with COVID in the last few days, along with what has happened over this past weekend with large groups of people coming together in Trinity Bellwoods and other parks, Dr. Williams is reluctant to move forward with that right away," Elliott said.

''There is a concern about people creating groups that are too large. So it is something that is coming forward but it has been pushed back a little bit."

Other highlights from today’s data:

  • GTA public health units account for 65.1 per cent of all cases
  • 56. per cent of cases are female and 43.1 are male
  • Close to 13 per cent of all cases involved hospitalization
  • Heath care workers represent about 17 per cent of all cases (4,485)
  • All but 93 deaths have been in people ages 60 and older and no one under 19 has died from the virus in Ontario
  • The number of people are currently hospitalized with the virus has dropped to 848 from 859
  • The number of people in intensive care dropped slightly to 143, down from 148, and 113 patients are on a ventilator, down 1 from the previous day
  •  Two more outbreaks were reported in long-term care, bringing the total number of outbreaks to 297