Canadian public health officials initially underestimated how deadly the coronavirus would be in long-term care homes and have revised their calculations in new modelling numbers shared on Tuesday.
But chief public health officer Dr. Theresa Tam says the data also shows Canada is slowing the overall spread of the first wave of the virus.
“We are making clear progress to slow the spread and bring the epidemic under control,” she said in a briefing with journalists to explain the new modelling data.
One factor in that, Tam said, is the fact that infected individuals are not infecting as many others.
When she briefed journalists on April 9, each infected person had spread the coronavirus to 2.19 other individuals, while the current transmission rate sees the virus spread to just over one other person.
However, while the COVID-19 fatality rate was initially calculated as roughly 2.2 per cent, Tam said the rate has now been revised to 5.5 per cent in light of a spike in deaths in long-term care homes.
Overall, deaths in long-term care and seniors’ homes account for 79 per cent of the total deaths in the country, according to the Public Health Agency of Canada (PHAC).
Individuals over the age of 60 account for 95 per cent of total deaths, PHAC’s newest numbers said.
Tam cautioned that the fatality rate could change again as the virus spread ebbs and flows.
“Until the epidemic is over, you actually don’t know the true case fatality rate,” she said.
“These are dynamic until you actually get to the bottom of the epidemic.”
Prior to the release of the data on Tuesday, Prime Minister Justin Trudeau cautioned that although the modelling shows the restrictions locking down the country are working, that doesn’t mean the danger has passed.
“In many parts of the country, the curve has flattened,” Trudeau said during his daily news conference outside Rideau Cottage in Ottawa.
“But we’re not out of the woods yet.”
PHAC updates short-term, but not long-term, projections
Health officials on Tuesday also provided a forecast for where things could be by May 5.
The new models suggest the country could see total deaths hit between 3,277 and 3,883 by next week, with 53,196 to 66,835 total confirmed cases.
The update comes nearly three weeks after PHAC first released projections for the COVID-19 pandemic.
Those projections — released April 9, based on the data that officials had at the time — laid out three possible long-term scenarios for how the pandemic might unfold in Canada based on strong, weak and no control measures for containing the virus.
Those first projections suggested that between 11,000 and 22,000 people could die from the virus in a “best-case scenario” where 2.5 to five per cent of the population is infected — but the new modelling data released on Tuesday did not alter those long-term projections.
“I think for our planning purposes, these three different scenarios are still useful at this moment in time,” Tam said.
On April 9, federal officials stated that the path ahead depended heavily on Canadians’ collective actions.
“The same holds true today,” Trudeau said on Tuesday.
Feds only have detailed info on 57 per cent of total cases in Canada
As of 2 p.m. ET on Tuesday, there are 49,804 confirmed cases of the coronavirus across the country, and 2,852 deaths linked to the virus so far.
However, as of Monday, PHAC only had received detailed data on approximately 57 per cent of the total number of cases reported to the agency, according to a daily epidemiological report.
The quality of the data shared by the provinces with PHAC has repeatedly been questioned by infectious disease and mathematical experts who point out it isn’t separated geographically and lacks detail distinguishing the dates of first symptoms from lab testing dates to the date a case was reported to health authorities — all of which can differ by weeks.
Dr. Howard Njoo, Canada’s deputy chief public health officer, admitted that acquiring complete data amid the pandemic is a challenge, but still maintained that the data the agency does currently have is “a good representation.”
“It is, to be honest … a bit of a weakness in terms of our collective system, the fact that at the federal level — our national level — we only get a certain percentage of the data,” Njoo said.
“We’re all working together, I think, really well. And I think in the future, to be quite honest, those are things we need to look at in terms of how data’s managed, how data’s collected, transferred — even at local level to provincial level, and then to the federal level.”
The challenge increasingly confronting public health officials is satisfying a public hungry for clear information about how long their lives will be disrupted and what measures they should be taking to stay as safe as possible.
Ian Schnoor, president and founder of The Marquee Group — which is Canada’s leading data modelling firm — said that was evident in the briefing with Tam and Njoo.
“People were desperate and craving for more insight and understanding of what the future might look like,” he said of the repeated questioning by journalists for further explanations of the models.
“You could hear the frustration in their tone.”
Schnoor said there should be a modelling expert at the briefings who can convey technical details like how the data was prepared, what assumptions anchor them and how those assumptions translate into action.
But that isn’t Tam, he said, adding it isn’t her job to do mathematical modelling.
“She’s the expert that can talk about public health measures that need to be put in place, she can talk about distancing and effective protocols that should be put in place and the way that the virus works and look for drugs and vaccines, but she was way out of her depth,” he said.
“Models need to be a communication tool and they’re not being used that way.”
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