What Saskatchewan's high COVID-19 test-positivity means for the province
Expert says the raw numbers are concerning, but more cases could be going undetected
Saskatchewan has ramped up its testing for COVID-19 and recorded the highest positivity rates of any province in Canada in recent weeks, but at least one expert says it's likely the province could still be missing hundreds if not thousands of cases every day.
"If we have 500 cases on a given day it's probably the true number is closer to 2,000," said Dr. Cory Neudorf, an epidemiologist at the University of Saskatchewan and the interim senior medical health officer with Saskatchewan Health Authority.
There are a variety of reasons why that is, said Neudorf.
The responses to the COVID-19 virus can vary, with some people having very mild symptoms or no symptoms at all while others are hospitalized or die. Those with mild cases may not be getting tested and could be spreading the disease to multiple people before they finally take action, Neudorf said.
One of the key ways of telling whether we're doing enough to detect COVID-19 is to look at the test positivity rate, or the percentage of tests that are coming back positive.
In Saskatchewan that number has been climbing since the end of July, when it was 3.5 per cent.
The province hit a rolling seven-day average high of 13 per cent at the start of October and it's only dropped down to 12 per cent in the past few days.
That puts the province among highest test positivity of any region in Canada.
As of Tuesday, the national seven-day average was 3.5 per cent.
The climbing case positivity has corresponded with an increase in testing.
During the week of July 5 to July 12, the province averaged 1,635 tests a day.
In the week of Oct. 5 to 12, the average number of tests completed in a single day had more than doubled, climbing to 4,002 tests a day.
Neudorf said analyzing whether the province is doing enough is not as simple as saying that more testing is better.
"What you want to see is test positivity going down while testing remains high, because that gives you more of a reassurance that things are more under control," he said.
That hasn't started happening in a significant way in Saskatchewan.
That means the province may need to increase testing to ensure a better understanding of the spread of the virus.
In the meantime, if the number of cases isn't as good an indicator, Neudorf said it's worth monitoring lagging indicators such as hospitalizations, ICU admissions and deaths.
However, those numbers might be telling us more about Saskatchewan's COVID-19 response than the spread itself.
"If you're just relying on those to tell you that we're in a serious state, the pandemic's already six weeks to two months past you. And that's kind of where we are right now," he said.
On Tuesday, the province recorded a new record high in COVID-19-related ICU admissions, with 80 patients across Saskatchewan. That means the province now has one more COVID-19 patient in the ICU than the total number of ICU beds provincewide pre-COVID.
Neudorf said there's no indication that we're going to see things get better in the next few weeks. But there are things that can make the province safer.
"We need to get people to voluntarily start doing more restrictions in terms of reducing the number of people you're contacting. Reducing unnecessary trips, trying to avoid crowds, all of those things that we got good at in the last wave," Neudorf said.
"We should be doing that now with or without government directives. That's what's going to get us out of this right now."
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