Ontario may have avoided worst case scenario but still faces weeks of high COVID-19 case counts, new modelling suggests
Published Thursday, October 29, 2020 3:06PM EDT
Last Updated Thursday, October 29, 2020 5:35PM EDT
New modelling suggests that Ontario will avoid the worst-case scenario that seemed likely earlier this month when it comes to the spread of COVID-19 but will continue to see high case counts through most of November.
The projections, prepared by the Ford government’s official modelling table, provide three different scenarios for what will happen over the next month as Ontario reaches the peak of the second wave.
In the more pessimistic scenarios it says that the province could see its daily case counts rise to 1,000 or 1,200 a day and then stay there for weeks but it says that the more likely outcome at this point is a trajectory similar to Michigan with cases coming down slightly to about 800 per day and then staying there throughout much of November.
The modelling also suggests that the number of COVID-19 patients in intensive care units will now only cross the 150 threshold in the “worst case scenario,” of average daily case growth of 1,200 cases per day.
That differs from modelling released three weeks ago, which suggested that Ontario would have more than 150 COVID-19 patients in the ICU in even the best case scenario by November, threatening the ability of hospitals to perform routine surgeries.
That modelling also suggested that Ontario would regularly see more than 1,000 cases a day by the second half of October, something that occurred for the first time on Sunday when 1,042 cases were reported.
“Most indicators are showing a slower growth in COVID-19 cases and the trajectory appears to be moving away from the worst case but cases are continuing to climb so it is not that we have crested and are now coming back down the other side of the epidemic curve. We are just getting into a slower period of growth,” Adalsteinn (Steini) Brown, who is the Dean of the Dalla Lana School of Public Health at the University of Toronto, told reporters on Thursday afternoon.
When the province last released modelling on Oct. 9 cases had been doubling every 10 to 12 days and there had been a nearly 250 per cent increase in hospitalizations related to COVID-19 over the previous three weeks.
Brown said that the growth has “softened” since then and we are starting to see “more of a gentle curve.”
Cases, however, continue to grow with Ontario’s seven-day average now standing at 899.
That is up 18 per cent from this time last week.
“It is still growing but it is a slower growth,” Brown said, noting that COVID hospitalizations have increased 56 per cent over the last three weeks. “All this translates into estimates of ICU use that are much more within the realm or the limits of the health system right now.”
Sharp increases in cases related to long-term care homes
Brown said that the modelling suggests that the province is no longer staring down “the worst case scenario” it was earlier this month when it appeared to be on a similar trajectory to hard-hit Victoria, Australia but he warned that things can dramatically change with COVID-19 and jurisdictions can have “rapid, rapid growth quite quickly.”
He also said that officials are starting to see “a much sharper increase” in cases in long-term care homes, raising concerns about a repeat of the devastation seen in the first wave of the pandemic when more than 1,800 long-term care residents died after contracting COVID-19.
“We have more deaths in the last week – 27 deaths - than we did between August 15 and October 8,” he said.
Significant regional differences
The province's new projections show significant differences in positivity rates and infection rates in different parts of the province, something that Brown says underscores the need for a “region-by-region approach to public health measures.
Peel Region had the highest positivity rate at 6.5 per cent and the highest number of new cases when adjusted for population. Toronto, meanwhile, had the second highest positivity rate at 4.8 per cent followed by York Region at 4.5 per cent, Ottawa at 3.1 per cent, Halton Region at 2.5 per cent and Durham region at 2.3 per cent.
Toronto also had the highest percentage of cases for which no epidemiological link could be found (65 per cent), in other words cases for which public health officials cannot pinpoint a source.
“We are seeing continued growth in cases. We are not going on a decline right now but we are not going on as steep of a curve,” Dr. Dirk Huyer, who is leading the province’s outbreak response, said during Thursday’s news conference. “We are still seeing people sick in the hospital, we are still seeing people in intensive care units and as Dr. Brown pointed out we are still seeing a number of people dying/ Having said that what we are illustrating is that there is some slowing of that growth which is so important because it speaks to the efforts that everyone is making.”
It should be noted that the modelling does not provide any projections on the total number of deaths that will occur as a result of COVID-19 but Brown expressed optimism that Ontario will be able to avoid the worst-case scenario of 15,000 fatalities that was laid out in modelling released in the spring.
The death toll, however, has already climbed to 3,118, surpassing the lower end estimate of 3,000 that was provided in that modelling.