The public health authority in York Region, north of Toronto, is reporting three cases of a new and highly contagious coronavirus strain that have no link to international travel, sparking concern that community spread is underway.
The strain, known as B117, was first identified in the United Kingdom and led to a rapid surge in cases.
Modelling released by the Ontario government this week predicted that community spread of the variant could cause COVID-19 infections to double every 10 days by March. Currently, the doubling time is between 35 and 40 days.
"There is evidence of community transmission occurring in York Region," medical officer of health Dr. Karim Kurji told CBC Toronto.
14 confirmed cases in Ontario
On Thursday, Ontario reported 14 confirmed cases of the new variant.
The number may seem low, given the supercharged transmissibility of the variant, but not many COVID-19 patients are being tested for it.
According to guidelines established by Public Health Ontario, only in a small number of circumstances, including those connected to travel, are samples scanned for B117.
As a CBC investigation found, the first known cases of the variant in Canada, in a couple from Durham Region, were discovered by fluke.
Currently, Public Health Ontario is testing between 500 and 600 samples per week for the variant. Ontario reported 3,326 new cases of COVID-19 on Thursday.
"We are continually watching for cases … and our lab system is developing specific tests that are utilized for identifying the U.K. variant as soon as possible," Ontario's chief medical officer, Dr. David Williams, said Thursday.
Is contact tracing keeping up?
The new strain has been proven to spread to others at a much higher rate, but it appears its arrival has not moved Ontario to adopt a new strategy for contact tracing.
A spokesperson for Toronto Public Health said that "there are currently no changes that have been made to the case and contact management process based on virus strain type."
The statement said Toronto Public Health follows direction from the provincial government for contact tracing protocol.
Ontario's Ministry of Health did not respond to questions.
Dr. Michael Warner, director of critical care at Toronto's Michael Garron Hospital, said authorities should be doing everything they can to find out more about new strains of the virus.
At this point, Warner said it's difficult to determine how severe community spread is based on limited testing.
"We're not testing enough people genomically to know how many variants there are," Warner said in an interview.
If community spread is under control, Warner said the government could close borders and restrict international travel in order to keep further cases of the new variant from coming into the country.