A highly-contagious coronavirus mutation first found in Britain will become the dominant strain in Ontario sometime in March, provincial modellers predict, narrowing the room for error as the province enters a period of sustained case decline.

Ontario Science Table Co-Chair Dr. Adalsteinn Brown told reporters it is now only a matter of time before the B.1.1.7 coronavirus variant becomes the dominant strain.

“Perhaps most worryingly the new variants of concern of the mutate SARS-COVID-2 virus are clearly spreading in the community and will likely be the dominant version of the virus in March,” he said on Thursday afternoon.

The admission is the first time health officials anywhere in Canada have made such a prediction.

Among many positive predictions about declining case numbers and likely lower hospital occupancy, Brown said that the variant presents a “significant threat to control of the pandemic,” which will require strict vigilance and adherence to public health measures at schools, long-term care homes and other congregate living settings.

“The countries that are fighting the new variant successfully are the same ones that have kept the public health measures in place,” Brown said. “If we are careful and we watch the data careful it should be possible to control the spread of the disease with schools open.”

Part of being careful will involve limiting travel into Ontario, Brown said when asked by a reporter about air travel.

“I think it’s really important to control inflow into the province if you’re going to control the spread of this variant or other variants.”

Modelling released Thursday suggests Ontario could see as few as 750 cases per day by the end of February, even with all schools open for in-class instruction and the B.1.1.7 variant overtaking so-called “wild” strains currently present in Ontario.

The B.1.1.7 coronavirus variant binds more easily with human cells than other variants and is approximately 50 per cent more transmissible than earlier variants.

It is believed to generate higher than normal viral loads in some older patients, and British health authorities believe it may be more deadly to patients over the age of 60.

Public Health Ontario is currently running every single positive case found on Jan. 20 through genomic sequencing in order to generate a “point prevalence” study showing just how far the variant has spread.

Ontario has confirmed 51 cases of B.1.1.7 so far, with several hundred more high probability variant cases tied to outbreaks at two long-term care homes in Barrie and Bradford-West Gwillimbury.

Simcoe-Muskoka District Health says that the Barrie outbreak at Roberta Place long-term care home has now left 50 of the home’s 128 residents dead.

It has also killed one essential caregiver and infected an additional 89 staff members and five other people linked to the home.

Public Health Ontario has also developed a new form of PCR nasal swab test that can detect all three known coronavirus variants of concern without having to resort to lengthy, laborious genomic sequencing.