Drop in cases is only part of the issue

Experts concerned over increasing number of variant-linked positives

As tens of thousands of schoolchildren return to in-person learning in the COVID-19 hot spots of Toronto, Peel and York Wednesday, the number of tests coming back positive for B.1.1.7 and other variants continues to increase, prompting infectious disease experts to warn of an all but inevitable third wave.

First, the good news. Ontario reported a total of 904 new cases on Tuesday, bringing the rolling, seven-day average down to 1,035 cases per day, with the hot spot regions in the GTA all continuing downward trends for new daily cases.

The bad news? While overall cases are down, more and more tests are coming back positive for not only the B.1.1.7 variant, but also for B.1.351, a strain that emerged in South Africa, as well as P.1, thought to have originated in Brazil.

“Because the new variants, in particular B.1.1.7 and B.1.351, are more transmissible, we’re not sure that the mitigation tools we have are sufficient to contain them,” said Raywat Deonandan, an epidemiologist at the University of Ottawa, noting that masks are still a great tool, but more discipline around their use will likely be needed.

“So putting (masks) on sloppily can’t be tolerated anymore, and having a one-layer mask probably isn’t going to do the job anymore. We probably should be encouraging highquality N95 usage across the board and we have to have a deeper conversation about aerosol transmission.”

The spread of B.1.1.7 in Ontario has seen an average daily growth rate of just over 10 per cent since late January, a Star analysis of provincial epidemiological data has found, while a total of 309 cases have been detected to date. One case of the B.1.135 variant was first detected on Feb. 1, and has since grown to nine cases. Most of those cases were found in Peel where five people living in a Mississauga condo building were found to have contracted the strain. Toronto’s one case of P.1 is the only case in the province reported so far.

According to the province’s COVID-19 Science Advisory and Modelling Consensus Tables, B.1.1.7 cases likely already make up between five and 10 per cent of Ontario cases, and the variant will soon become the dominant one.

“The variants are certainly of concern,” said Dr. Lawrence Loh, Peel’s medical officer of health, in an interview with the Star.

“We are increasingly seeing that while our trend is on the decline, our decline is slowing to some extent … we know that many of the tests that are being screened for variants are increasingly coming back more and more positive for variants.”

According to provincial data, cases of B.1.1.7 in Peel have grown at an average daily rate of 14.3 per cent since Jan. 28, when the province began reporting the number of variant cases detected. The region has the highest such growth rate in the GTA, with York seeing an average daily growth rate of B.1.1.7 of 8.1 per cent and Toronto measuring in at 5.5 per cent.

Loh added that he is concerned that the old strain of the virus might be “crossing streams” with more contagious new variants, which could quickly reverse the region’s downward trend in cases if the economy is reopened too quickly.

Peel, along with York and Toronto, are expected to be the last regions in Ontario to transition back to the province’s colour-coded COVID-19 response framework on Monday.

Loh said if Ontario wants to keep schools open to ensure children can obtain the mental health benefits of socialization and in-person education, precautions must be taken.

“If we really want to keep schools open and ensure that children can obtain these benefits, and if we really want to make sure that we’re continuing to protect our vulnerable, especially our essential workers in Peel who really bear the brunt of our high rates of transmission, we really do need to look at how we are reopening the rest of the community,” he said.

Toronto Public Health has made some changes to its student and staff screening tool amid the threat of new variants, including prohibiting all children from attending school if anyone in their household has COVID-19 symptoms. Should the person experiencing symptoms decline a COVID test, children who attend school in the household cannot return to school for 10 days.

The tool also requires children who live in households in which a family member has travelled in the last two weeks to stay home from school for the full 14-day quarantine period.

To date, Toronto has recorded 37 cases of B.1.1.7 and one case of P.1.

Colin Furness, an infection control epidemiologist at the University of Toronto, says he believes that within two to three weeks, variant cases will become dominant “and then we’re going to start seeing a rise.”

“(Overall) cases are going down, except variant cases are rising,” he said. “My own sense is that’s going to take the month of March to really climb and I think by early April, we’re going to be in a bad situation.”

“We need to look at how we are reopening.”

DR. LAWRENCE LOH

PEEL MEDICAL OFFICER OF HEALTH