KITCHENER -- The Region of Waterloo's top doctor said COVID-19 case rates remain at red tier levels.

Speaking at the regional Board of Health on Wednesday, Medical Officer of Health Dr. Hsiu-Li Wang said new cases are starting to pick up again.

As more variants of concern show up around the area, Dr. Wang said it's critical to get a handle on case numbers now.

Provincial modelling predicts a sharp rise in variant cases across Ontario. Regional officials have confirmed 10 cases of the B.1.1.7. variant that was first found in the U.K. Another 108 have screened positive for a variant of concern, but the specific variant hasn't been determined yet. This makes up about 20 per cent of recent cases.

Dr. Wang said the situation could easily get worse.

"Our rates continue to be firmly in the red zone and our situation is very precarious," she said. "As the variants are becoming more prominent locally, the more contacts we each have, the more likely the virus will spread."

The region's first mass vaccination site will open in Waterloo on Thursday for priority groups in Phase One, including adults over 80.

Another site is expected to open in Cambridge next week, although the exact location hasn't been announced yet.