Ontario’s chief medical officer has denied a request by local public health officials to resume mandatory masking in schools, pharmacies or other workplaces, saying it is not necessary at this time.

Earlier this month, local medical officers of health from Niagara, Windsor-Essex and Peterborough asked Chief Medical Officer Dr. Kieran Moore to reinstate the mandatory mask order in a variety of settings including schools, stores and workplaces, saying hospitalizations were already forcing the cancellation of scheduled surgeries at hospitals in their regions.

“The return of masking could help protect those with inequities and vulnerabilities, relieve the pressures on our hospitals, and most importantly protect the health of the people we serve,” doctors Thomas Piggott (Peterborough), Mustafa Hirji (Niagara) and Shanker Nesathurai (Windsor-Essex) wrote.

In his response dated May 6 and released Thursday by the Ministry of Health after an inquiry by CP24, Moore says their request is not needed.

“As I have throughout the course of the pandemic, I will continue to monitor the data and the COVID-19 situation across the province to assess the need for any changes to the Class (masking) Order or other public health measures at a provincial level,” Moore wrote.

Public Health Ontario said last month that the decision to end mandatory masking in those settings on March 21 was “temporally associated” with the start of Ontario’s sixth wave.

The end of masking led to a significant increase in virus transmission in the province’s public schools, with absences among staff and students up approximately 40 per cent between the end of March and the start of April.

Several school boards tried to pass individual mask mandates on their own but only one in Ottawa was successful.

Others, such as the Toronto District School Board, have had to return to almost daily notifications to parents about new cases at schools.

In his letter, Moore reiterated his strong recommendation that everyone continue to mask in indoor public settings as much as possible.

“While the class order for masking applies only to specific settings, I continue to strongly recommend that people wear a well-fitted mask in any indoor public settings, particularly where physical distancing is not possible.”

Masks are still required in all Ontario hospitals, long-term care homes, retirement homes and public transit vehicles until at least June 11.

Between the announcement of the end of mandatory masking in schools and stores in early March to the end of April, the Institute for Health Metrics and Evaluation (IHME) in Washington State estimated Ontario’s mask use fell from 71 per cent to 42 per cent.

Also on Thursday, Moore told the Canadian Press the province was in for a "calm summer" with COVID-19, but he was still concerned with new subvariants of Omicron circulating elsewhere in the world.