New modelling released by the Public Health Agency of Canada (PHAC) projects that more transmissible COVID-19 variants could drive a resurgence of coronavirus cases across the country without stronger public health measures in place to prevent their spread.
The modelling shows the current trajectory of the national epidemic coming under control, with numerous key indicators such as case counts, hospitalizations and long-term care outbreaks declining in recent weeks. But the spread of more contagious virus variants threatens to reverse that progress.
“With the emergence and spread of new variants of concern, we are cautioned that unless we maintain and abide by stringent public health measures, we may not be able to avert a reacceleration of the epidemic in Canada,” said Chief Public Health Officer, Dr. Theresa Tam at a virtual news conference on Friday.
“These variants have been smouldering in the background and now threaten to flare up,” she said.
Tam said there are currently fewer than 33,000 active cases in Canada, a 60 per cent drop compared to a month ago.
At the same time, over 700 cases have been linked to three variants of concern — the B117 variant first identified in the U.K., the B1351 variant first identified in South Africa, and the P1 variant first traced to travellers from Brazil. Variant cases have been detected in 10 provinces and there is evidence of community spread in at least five.
Short- and long-term forecasts that exclude the spread of COVID-19 variants show infection rates flattening and declining in the coming weeks, even if people maintain the current number of contacts they have each day. However, when the more contagious variants are included, projections show a dramatic spike in cases to over 20,000 per day by mid-March if public health restrictions are relaxed further.
The modelling shows a similar dramatic spike by mid-April even if the current level of restrictions are maintained.
“Further lifting of the public health measures would cause the epidemic to resurge rapidly and strongly,” Tam said. “And current community-based public health measures will be insufficient to control rapid growth and resurgence as forecast.”