BARRIE, ONT. -- The health unit is reporting four new cases of COVID-19 in Simcoe County on Tuesday.

The new cases are all women from Bradford, Barrie, Penetanguishene and Innisfil.

There have been 616 confirmed cases since the pandemic started in Simcoe Muskoka, and the health unit reports that 559 of those have recovered.

Currently, four people are fighting the virus in the hospital, while 36 people have died locally after becoming infected.

Meanwhile, Ontario's hospitals are warning the province to prepare the health-care system for a potential second wave of COVID-19 this fall.

The Ontario Hospital Association says the government must develop a contingency plan to ensure regional service and staffing plans are in place ahead of a possible surge.

OHA president Anthony Dale says a potential second wave will likely collide with flu season, adding significant pressures to hospital operations.

The call comes in reaction to the government's decision to move most of Ontario to Stage 3 of reopening on Friday, including Simcoe Muskoka.

Dale says moving to Stage 3 will represent a heightened risk for the province, and it must be prepared to respond.

Ontario is reporting 111 new cases of COVID-19, along with one new death due to the novel coronavirus.