Ontario's COVID-19 case counts are unreliable, so these metrics will tell us when Omicron wanes

As the Omicron variant sweeps through Ontario at a rate never before seen during the COVID-19 pandemic, nearly everyone wants to know when we'll be on the other side of this wave.

But now, restrictions to PCR testing criteria mean case numbers no longer present an accurate picture of the spread of the virus — and while case counts alone were never a perfect metric, they did provide the simplest window for people to understand what was happening in their region.

So with that option gone, how can Ontarians measure risk and decide what choices are best for living their lives, and moreover, how will we know when this wave is truly waning?

According to experts, the best answer is: by analyzing several different things.

Both the provincial chief medical officer of health and Toronto's medical officer of health were asked this week about what indicators are being used to inform public health restriction decisions, and both said hospitalizations were at the top of the list. 

"The most important metric that we're monitoring is the hospitalization rate," said Dr. Kieran Moore, Ontario's chief medical officer of health, during a Monday news conference.

"Certainly, hospitalization is going to be one of the key indicators," echoed Dr. Eileen de Villa, Toronto's medical officer of health, during an interview on CBC Radio's Metro Morning Wednesday.

Hospitalizations are referred to as a "lagging indicator," in that they tend to represent infections that happened a few weeks prior. Epidemiologist Tim Sly, professor emeritus at Ryerson University, told CBC News that generally, it can take around five weeks from the point that someone is infected with COVID-19 to the point that they end up in intensive care.

"Really, the only thing that people are looking at now is hospitalization rates, because you can't really fudge those, or miss them, or misconstrue them," Sly said.

The province reported Thursday that hospitalizations and admissions to intensive care for Ontarians with COVID-19 were climbing. 

There were 2,279 people with the illness in hospitals, up from 2,081 the day before and a 136 per cent increase from the same time last week. The pandemic high of 2,360 hospitalizations came on April 20, 2021.

Similarly, there were 319 people with COVID-19 in ICUs. That's up from 288 patients the day before and 119 more than the previous Thursday, when 200 needed intensive care.

A recent report from Public Health Ontario found that while the risk of hospitalization and death was 54 per cent lower for Omicron than the Delta variant — but the fact that it is infecting so many more people may actually lead to an overall increase in hospitalizations. 

There are other metrics that officials are using to measure the spread of the virus.