TORONTO — Public health measures and vaccinations have flattened the fourth wave of COVID-19 in Ontario but the situation remains fragile and unpredictable, the province's science advisers said in a new report Tuesday.
"We're walking a narrow ledge," the Ontario COVID-19 Science Advisory Table said in an online statement. "We're OK for now, but we have no wiggle room."
The group noted that cases, hospitalizations and intensive care admissions are currently not increasing in the province as vaccination coverage grows.
But it noted that trends vary across the province. While test positivity is down overall, that's not the case for all age groups – infections are on the rise among young children who aren't currently eligible for vaccination, the group said.
Cases are also increasing in 19 out of 34 public health units, though large, dense regions like Toronto and Peel are reporting decreases, it said.
New models from the group show daily case counts could increase next month and into November, with more than 1,000 cases if the status quo in public behaviour and policy holds, and 5,000 cases daily if transmission increases significantly. If transmission decreases 25 per cent, Ontario could see daily infections in the low hundreds.
The group cautioned that there's uncertainty in their predictions because it's too early to see the impact of in-person schooling and work resuming, and of people possibly spending more time indoors during cold weather.
Ontario reported 466 new COVID-19 cases on Tuesday and its daily infections have remained under 1,000 during the fourth wave.
Beate Sander, a member of the advisory group and an infectious diseases researcher, said Ontario's flat case rate was unexpected and though the factors behind the trend aren’t fully understood, there are some possible explanations.
"Really what it comes down to is vaccines and contact," Sander said in an interview.
Vaccines seem to have been effective at preventing infections and mobility among the population has stayed unexpectedly stable, she said. The province said 86 per cent of eligible residents have one dose of a COVID-19 vaccine and 80 per cent have received both shots.
Despite the positive overall trends, Sander described the pandemic situation in Ontario as a "tightrope."
Increasing contact between people could lead to a rapid rise in cases and reducing contacts even slightly could set the province on a better trajectory for the coming months, when the rising cases in unvaccinated kids will likely spread to others, she said.
"The increase in cases in kids will eventually kind of trickle through to other age groups and to the rest of the population, it just takes time," she said.
Unvaccinated people continue to make up the majority of cases, hospitalizations and intensive care admissions, the group reported.
Those who aren't immunized against the virus have a sevenfold higher risk of experiencing symptoms from a COVID-19 infection, 25-fold higher risk of being hospitalized with the virus and 60-fold higher risk of being admitted to intensive care, it found.
Ontario has, so far, avoided the crushing fourth-wave hospitalizations that have struck provinces in Western Canada that did away with major public health restrictions like masks and other rules this summer.
The science table estimates that intensive care occupancy in Ontario could vary from 200 beds to more than 300 by the end of October, again depending on whether transmission increases. Reducing contacts between people early and "a cautious approach" will help lower the risk of a rapid rise in ICU admissions, the group said.
A spokeswoman for Health Minister Christine Elliott said the modelling shows Ontario's "extremely cautious approach" to keep masking rules and other measures in place is paying off.
She also pointed to Ontario's recent policy requiring vaccination proof for entry into certain businesses as one that will "help protect the province’s hard-fought progress."
"In the months ahead, we will maintain our cautious approach and continue to make decisions based on the best medical and scientific advice," Alexandra Hilkene said in a statement.
NDP Leader Andrea Horwath said the modelling shows more must be done to protect school-aged children from COVID-19.
"New modelling from the Ontario Science table shows the COVID situation is fragile and the danger to children is real," she said in a statement. "With cold weather around the corner, now is not the time to let our guard down."
Horwath called on the province to bring in more safety measures in schools and to have a provincial plan for vaccinating children aged five to 11 once Health Canada approves the shots for them.
This report by The Canadian Press was first published Sept. 28, 2021.
Holly McKenzie-Sutter, The Canadian Press