Ontario COVID-19 modelling examines long-term effects of virus

Ontario’s latest COVID-19 modelling shows that hospitalizations and ICU occupancy are stable as officials examine how the long-term effects of the virus will vary in certain people.

The group says 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’s Science Advisory board says high vaccination rates remain integral in control over case growth and continued public health measures. Further, the science table says vaccine coverage is growing slowly, with a higher cumulative number of vaccinated individuals over a seven-day average.

The health table also looked at how “Long COVID” will significantly impact the health of thousands of Ontarians.

“About 1 in 10 individuals with COVID-19 infection will continue to have symptoms lasting more than 12 weeks (estimated 57,000 to 78,000 individuals in Ontario based on data up to August 2021),” the science advisory board writes.

The most common symptoms include fatigue, shortness of breath, pain, anxiety and depression, and trouble thinking and concentrating, also known as brain fog.

Vaccines reduce the risk of infection by 85 per cent and diminish the chance of developing “Long COVID-19” in breakthrough infections by about 50 per cent, they add. The science table also says that residents who contract the virus and produce long-term effects could lead to an increased incidence of new chronic conditions, such as diabetes or cardiovascular disease, as well as the “severe impairment of home-life and day to day activities for some individuals.”

In what the board calls a comprehensive follow-up study consisting of 12 months, they concluded that 12 per cent of all infected individuals had not returned to work. Among the 88 per cent who did return, approximately 24 per cent had not returned to their pre-COVID-19 level of work.

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The group says the fourth wave of infections has currently flattened thanks to public health measures and immunizations, which have proven effective at keeping people out of the hospital.

A spokesperson for health minister Christine Elliott said the latest 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.”

“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,” spokesperson Alexandra Hilkene said.

“The implementation of vaccine certificates in higher-risk settings will help protect the province’s hard-fought progress. We are seeing the impact of this policy, with thousands more rolling up their sleeves for first and second doses each and every day.”

Despite the stability being seen in hospitals and ICUs, the science group notes that COVID-19 cases are on the rise among young children aged five to 11 who aren’t currently eligible for vaccination.

Data from late August shows roughly 30 new infections per 100,000 of the population in this age group, but that has grown to over 50 since mid-September. Similar but less substantial growth is being seen in children aged 12 to 17.

Toronto Public Health announced Monday it’s preparing to start offering vaccines to children between five and 11 years old. TPH says this is based upon Health Canada approval and receipt of vaccine for this age group from Ontario’s Ministry of Health.

The models 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.

Ontario’s daily case counts have so far remained under 1,000 during the fourth wave, and the graph of Ontario’s seven-day average roughly shows a plateau since the beginning of September.

That’s well under the worst-case scenario in Ontario’s previous modelling, which showed about 4,000 daily cases by now.

Reality is more in line with the best-case scenario, in which cases would have steadily fallen since September 1st.

“In the months ahead, we will maintain our cautious approach and continue to make decisions based on the best medical and scientific advice.”

With files from The Canadian Press