The joint letter is addressed to Ontario's Chief Medical Officer of Health Dr. David Williams. Vera Etches of Ottawa co-signed it.
Toronto had the highest number of new infections reported Monday with 906, while Peel Region reported 533 and 391 cases were in York Region.
Authorities in Ontario and Quebec expressed concern on Monday that the recent rise in COVID-19 cases was putting renewed strain on the health-care system, as both provinces sought to contain the spread of the virus.
The Ontario government has said it will not duplicate the paid sick leave program run by Ottawa, but Tory said rising case counts and the resulting pressure on the province's hospitals show that approach needs to be reconsidered. The number of COVID-19 patients in hospital jumped from 23 on March 19 to 53 on April 5, while the number of people in the ICU with COVID-19 quadrupled from four to 16.
The letter asks Williams to issue a province-wide stay-at-home order, close non-essential businesses (and be stricter about which businesses quality as "essential"), mandate staffing limits where possible, set strict capacity limits in open businesses, restrict people from travelling within Ontario, offer paid sick days to essential workers and move schools online in hard-hit areas. Quebec now has 123 people in intensive care for COVID-19, which is still well below the stated capacity of 383.
Dr. Eileen da Villa also called the rising COVID-19 case rates in the city "horrific".
Ontario said 121,577 doses of a COVID-19 vaccine were administered since the last report on Saturday, bringing the total number of inoculations so far to 2,545,640.
"It's critical to point out that after applying public health measures it takes time for the intended effects of the measures to be realized due to the incubation period of the virus", Alex Hilkene said in a statement.
"Our government will continue act on the advice of the Chief Medical Officer of Health who will review the science, data and trends along with collaborating with local medical officers of health and our team of expert health officials on if and when public health measure can be loosened or strengthened".
There are 942 people hospitalized with the virus in Ontario, but the Ministry of Health notes that 10 per cent of Ontario's hospitals do not submit data on weekends.