Ontario's COVID-19 case counts 'flattened' but exponential growth still possible if restrictions lift: modelling

TORONTO -

A group of scientists advising the Ford government say that the fourth wave of the pandemic appears to have “flattened” but they are warning that there is “no wiggle room” with new modelling now pointing to an exponential rise in cases should restrictions be lifted prematurely.

The projections, released by Ontario’s Science Advisory Table on Tuesday afternoon, suggest that the rolling seven-day average of new cases is on track to hover under 1,000 through much of October before rising to around 1,500 by by the beginning of November, assuming there is no change in policy or behaviour.

But the projections warn that should Ontario lift most remaining restrictions, a scenario that the scientists concede is unlikely, case counts would likely surpass 5,000 by the end of November.

In a more optimistic scenario, based on a 25 per cent reduction in transmission, case counts would steadily decline and dip down to a few hundred a day by November.

“There is a wide range for case projections, reflecting the fragile situation and high degree of instability as colder weather approaches with more time indoors,” a presentation accompanying the new figures states. “Continued control over case growth requires high vaccination rates in the eligible population, continued public health measures, and a flattening of growth in mobility.”

The last projections released by the science table back on Sept. 1 warned that daily case counts could reach 4,000 a day by October if the province continued along the trajectory it was on then.

But the projections also suggested that Ontario could see case counts begin to decline so long as residents reduced their contacts marginally and the province has, in fact, charted closer to that “best case scenario” with it’s rolling seven-day average now standing at 606, down from 701 on Sept. 1.

In a series of messages posted to Twitter on Tuesday afternoon, the science table said that Ontario is currently “walking a narrow ledge” with case counts increasing in 19 of the province’s 34 health units as well as among the cohort of school-aged children that are not yet eligible to be vaccinated (ages 5 to 11).

The scientists also warned that it is “too early to see the impact of increased contacts with return to school and workplaces,” creating further uncertainty as we head into October.

“The bottom line: we’re doing well for now. But if we want to control cases, hospitalizations and deaths we must increase vaccination rates again and keep current public health measures to limit contacts until many more (& younger) Ontarians are vaxxed,” they said.

Hospitalizations are likely to rise but not rapidly

Hospitalizations in Ontario slowly rose through much of August as the Delta-driven fourth wave of the pandemic unfolded but have been mostly steady for several weeks now.

The modelling released by the science table on Tuesday said that the current trajectory that we are on suggests that there will be a gradual increase in the number of COVID patients in the ICU from 180 as of Monday night to closer to 300 by the end of October.

But it also says that any high risk of a rapid increase in ICU occupancy can be negated “with a cautious approach and early contact reductions.”

In fact, the scientists say that Ontario’s favourable situation compared to some other provinces is likely due to the fact that “we’ve kept enough public health measures in place to keep some control on contacts,” even as businesses reopened and larger gatherings were permitted.

“Today’s modelling further reinforces that as a result of Ontario’s extremely cautious approach, including maintaining strong public health measures such as indoor masking, the province’s public health and health care indicators remain stable or are improving,” a spokesperson for Minister of Health Christine Elliott said in a statement provided to media outlets. “In fact, Ontario continues to report one of the lowest rates of active cases in the country, well below the national average, as we have trended toward the best-case scenario projected in the last modelling.”

More to come...