The Region of Waterloo is listed at the lowest level in Ontario's new tiered COVID-19 restriction system.

The provincial government outlined the new system at a press conference on Tuesday afternoon.

Waterloo Region is listed as green, which is the “prevent” category. The province says regions at that level need to focus on education and awareness about public health safety measures. The restrictions at the green level reflect those in Stage 3 and will remain in place until there is a vaccine or treatment widely available to the public.

The province says highest-risk settings need to stay closed.

The province's release says green status is assigned to health units with a weekly incidence rate of fewer than 10 cases per 100,000 people and a test positivity rate under one per cent. Last week, Medical Officer of Health Dr. Hsiu-Li Wang said the region was averaging 16 cases per 100,000 residents per week, and was fluctuating between a 1.1 per cent and 1.6 per cent positivity rate.

"Although our region is in the green today, we know with COVID-19 that things can change quickly," Dr. Wang said in a statement to CTV News. "It is also important to note that the province has indicated that it's based on data from the previous week and that updated data will be used for final categorization which we can expect Friday."

Most Ontario regions are listed in the green level, including Wellington-Dufferin-Guelph Public Health, Region of Waterloo Public Health and other surrounding municipalities. However, Brant County Health Unit is in the yellow zone.

The other levels are Protect (yellow), Restrict (orange), Control (red) and Lockdown.

Yellow restrictions include enforcement and fines, along with additional public health measures at higher-risk settings like restaurants, gyms and movie theatres.

Dr. Elizabeth Urbantke, Acting Medical Officer of Health for the County of Brant, said the region's classification is at the proposal stage.

"We have been told that follow-up conversations between the Chief Medical Officer of Health and local health units will take place before anything is finalized," a statement from Dr. Urbantke said in part. 

Some COVID-19 hotspots are in yellow or orange levels. No regions are currently in red or lockdown.

The list released on Tuesday used data from the week of Oct. 26. A finalized list is expected on Friday.

With files from CTVNewsToronto.ca's Sean Davidson

Read the province's information on restrictions here:

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