Regions with the highest case counts were Toronto with 343, followed by Peel and York Region with 186 and 89 cases. There are three known active cases.
The district is experiencing an increase in COVID-19 variant cases, which the health unit says is particularly worrying because variants spread more easily.
Testing numbers are typically lower in the days following a weekend.
"We are ensuring through our vaccine distribution that the people most close to their communities - the public health units - are making the decisions on what is the fastest and easiest and most equitable way to ensure that people get the vaccines they need", she said.
The province has reported 45 new hospitalizations since yesterday, and six new admissions of COVID-19 patients to intensive care units.
There have been 295,119 confirmed cases of the novel coronavirus in Ontario since the pandemic began, 277,939 of which have been resolved and 6,884 that have led to death.
There were five new cases involving a confirmed variant of concern.
Ontario's seven-day daily case average is now 1,045, slightly lower than the average last week of 1,051 cases.
The province also said 54,852 people were tested on Tuesday and 17,141 additional doses of the vaccine were administered.
The province has received a total of 35,015 doses of COVID-19 vaccine, and are holding 8,698 in reserve for second doses and planned clinics.
The individual, who travelled from Southeast Asia to the Kingston region and tested positive for COVID-19 on February 18, was only exposed to one other identified individual. After the first reported cases on September 20 in the United Kingdom, it quickly became the most dominant strain in the southeast of England. There are 3 confirmed variants of concern (VOC) cases, both are the United Kingdom (B.1.1.7) strain.
"It will it even (be) before September, I think, depending on a number of factors, such as vaccine uptake, ongoing monitoring of other variants, and how vaccine coverage is provided", Dr. Theresa Tam said Tuesday at a news conference in Ottawa.
Dr. Kieran Moore, medical officer of health for Kingston, Frontenac and Lennox and Addington Public Health, said the scenario in Kingston was a "good news story" in the context of the Canadian government's newly implemented quarantine process and testing requirements for worldwide travellers.
According public health officials, 975 new infections were confirmed on Tuesday.
The case is under investigation and the individual is said to be self-isolating.
All positive tests in Ontario are being analyzed for variants of concern.