The modelling also projects that the number of intensive-care patients from COVID-19 could drop below 200 by mid-July, allowing normal hospital service to resume and giving the province a chance to start tackling the massive care backlog generated by the pandemic.
"The Delta variant is more transmissible and may cause more severe illness", said Dr. Juli Emili, associate medical officer of health for the region.
"I think it is critical to try to get that first dose into as many people as we can across the province and accelerate that second dose into high Delta risk communities so we can protect against the kind of surge we have seen in the United Kingdom", Brown said.
"This is not a doomsday scenario ..."
A second dose of the vaccine adds 50 per cent effectiveness, officials said.
The Ontario government is accelerated the administration of second doses of COVID-19 vaccines in Delta hotspots on Monday, June 14.
"Mobile vaccine units supported by province operated pop-ups and employer-led clinics that provided first doses in Peel, Toronto and York public health regions will also begin operating second dose clinics beginning the week of June 20, 2021", notes the province.
However, if virus spread is high with the same vaccination rate, cases could spike back up to 2,500 per day.
In a medium scenario, that number could jump back up to almost 1,000 cases per day by August.
Health officials logged 590 new infections on Thursday, as well as 11 deaths related to the novel coronavirus.
Individuals who received a COVID-19 vaccine outside of Ontario or Canada are required to provide proof, such as a vaccination receipt or certificate, to their public health unit in order to be registered in the system.
There are nearly 1.4 million people fully-vaccinated with double doses of vaccine.
In total, over 10.6 million vaccine doses have made it into the arms of Ontarians.