Manitoba COVID-19 data skewed due to testing backlog, epidemiologist says focus on hospitalizations

There are thousands of COVID-19 tests in Manitoba still waiting to be analyzed, and the backlog has led to a targeted testing approach and a skew in the daily information being shared publicly.

Last year Tara Moriarty, an associate professor and infectious disease researcher at the University of Toronto, set out to collect COVID-19 information to help people understand the impact of vaccination.

She now uses her daily spreadsheets to calculate how many severe outcomes in Canada may happen related to the Omicron variant.

“The current estimates right now, if 90 per cent of the population was infected, is that would translate into about 72,000 or 71,000 deaths,” said Moriarty.

With how transmissible the Omicron variant is, Moriarty said knowing how much virus there is in the country has become tricky—even for modellers.

“I don't think we’re really going to know until things slow down and it's going to take quite a while to figure out how many people have been infected," she said.

In Manitoba, public health officials have said daily case counts are under-reported due to testing backlogs.

On Tuesday, the province reported more than 1,700 new cases and a five-day test positivity rate of 39.5 per cent—a rate that is also skewed higher because lab testing is targeted.

“Don't change your actions based on test positivity or on case counts—just change your actions now to decrease the amount of contacts you have," Dr. Brent Roussin, Manitoba's chief public health officer, said last week.

Cynthia Carr, an epidemiologist and founder of EPI Research Inc., said the most important stats are and have always been hospitalizations and ICU admissions because that is what needs to be managed.

"We need to manage not just the resources needed for COVID-19 patients but what is the impact on that hospital capacity so we can please start doing more elective surgeries, more diagnostic testing,” Carr said.

Moriarty said one province to watch is Quebec because data is reported quickly and quite completely.

She also suggests people should start assuming that at least one in every 10 people they come in contact with has or recently had COVID-19.

“A lot of us don't have a choice about being indoors with other people for example because we have to work or for other reasons," she said. "But where you do have a choice, use that choice.”