Why the West appears to be ‘flattening the curve’ better than central Canada
For weeks, Canadian political leaders and public health officials responding to the COVID-19 pandemic have repeated the same mantra: "We're all in this together."
But that hasn't stopped observers in the academic community and the media in recent days from highlighting differences in outcomes between provinces - differences laid bare in colour-coded charts, maps and graphs.
While scientists caution that the way provinces collect and report coronavirus data is not uniform, they say there is no denying the broad patterns and trends: the West is generally faring better than central Canada at "flattening the curve."
"It does appear that B.C. and Alberta seem to be doing better than Quebec and Ontario," said Jeff Kwong, an epidemiologist and public health professor at the University of Toronto.
Why this is happening cannot be answered in simple sound bites. Some of it relates to important policy decisions and public messaging in the early stages, experts say. Some of it can be chalked up to circumstance and pure luck.
At the core of the discussion though is the data.
In recent weeks, Isha Berry and Jean-Paul Soucy, two PhD students at the University of Toronto's Dalla Lana School of Public Health, have been collecting coronavirus case numbers from across the country and then presenting the results online using different visual tools. The site is updated daily.
"Being able to compare outcomes is useful to tell what strategies are most effective," Soucy said.
What do their charts show? As of the start of the Easter long weekend, the cumulative number of reported COVID-19 cases continued to climb in Quebec (10,912) and Ontario (6,401), while there was more of a levelling off in B.C. (1,370) and Alberta (1,451). The rise in the cumulative number of reported deaths was also much less steep in the West compared to central Canada.
Kwong said one factor that could be contributing to the trend is greater availability of testing in some provinces compared to others. As of Thursday evening, the rate of testing per 100,000 people was 605 in Ontario compared to 1,598 in Alberta, 1,368 in Quebec and 1,048 in B.C.
"Until recently, Ontario had a backlog of tests, so the turnaround time - the time from obtaining a swab to providing results - was longer than ideal," Kwong said.
Delayed identification of cases in turn leads to delays in contact tracing - finding all the individuals that a person who tests positive for COVID-19 had come into contact with - leading to the spread of more cases, he said.
"Hopefully, that will be less of a factor moving forward for Ontario with resolution of the testing backlog."
Soucy agreed. Testing in Quebec has only ramped up in the last couple of weeks, whereas Alberta has been a "consistent leader in tests per capita." B.C. has also been "fairly good" at testing, he said.
"The provinces that have done a lot of testing consistently seem to be doing better."
Experts also pointed to differences in the way authority figures reacted in the earlier stages of the outbreak. In Ontario, public health officials "doubled down" on the notion that there was no community spread "at a time that was clearly untrue," said David Fisman, an epidemiology professor at the University of Toronto.
By contrast, the public messaging in B.C. was more clear and cohesive, said Mohsen Sadatsafavi, an epidemiologist and health outcomes scientist at UBC.
"B.C. got it right on several fronts," he said, citing better co-ordination between the provincial ministry of health, health authorities, and the B.C. Centre for Disease Control.
The role of Dr. Bonnie Henry, the provincial health officer, "as an effective leader is undeniable," he added, citing her "honest pleas for self-isolation."
Sadatsafavi said while scientists still do not fully understand the nuances of COVID-19 transmission, "it appears that B.C. did not have a 'super spreader' that seeded COVID-19 in multiple locations."
By contrast, there was a "pretty clear" super spreader event in Ontario, Fisman said, citing a large international mining convention sponsored by the Prospectors and Developers Association of Canada held in the early days of March in Toronto.
That said, South Korea also had an early super spreader event - a woman infected dozens of worshippers at her church, according to media reports - but the country was able to bring its "A game" to control the spread, Fisman said.
There was also a large dental conference in Vancouver during the first week of March linked to dozens of cases, Kwong noted, so it's hard to say if super spreader events are, in fact, a major factor in different provincial outcomes.
"Adequate availability of testing and rigorous contact tracing can probably overcome super-spreading events," he said.
In an interview with the CBC, Fisman credited B.C. for implementing rules last month ordering long-term care workers to work at only one facility. Ontario has not mandated such a move.
Experts have also identified the timing of spring break as another possible factor. Quebec's spring break fell at the beginning of March - before all the travel warnings and the declaration of a pandemic. In Ontario and B.C., spring break happened in mid-March.
By the time Quebec officials like Premier Franiois Legault started asking people to self-isolate and stay at home, many families had already returned from their vacations abroad.
"All those people had been back circulating for a week," said Erin Strumpf, a professor of health economics at McGill University.
"Just by dumb luck, Ontario's break was later."
But the public messaging for how families should spend their break was different. On March 12, B.C. officials advised against all non-essential travel outside of Canada. By comparison, Ontario Premier Doug Ford that same day did not discourage people from travelling, telling reporters families should "have a good time."
Strumpf said she wonders if B.C.'s proximity to Washington state, the site of the first coronavirus "hot spot" in the U.S., may have been an influence. The first case was detected in that state on Jan. 21.
"It seems obvious to me B.C. would've been worried a month or two before Ontario and Quebec," she said.
Experts stress that when doing province-by-province comparisons, it's important to keep certain caveats in mind. Not only are there differences in how often provinces are testing, there may be variations in who they're testing as well. Testing criteria within provinces can also evolve over time, as well as the way in which provinces report numbers.
A few weeks ago, Quebec required that a positive test result in a hospital lab needed to be augmented with a positive test result in a provincial lab. When the province eliminated that second step, there was a huge spike in reported cases.
"It is always worth taking a deep breath, thinking about what are other possible explanations" for variations in provincial outcomes, Strumpf said.
And while the growth rate appears to have slowed in Western provinces in comparison to Ontario and Quebec, there are a lot of things that can respark infections.
"We need to see sustained amounts of flattening or lower growth rates to feel more confident or draw stronger conclusions," Berry said.
Heading into the long weekend, B.C. officials reiterated this week that now is not the time to get complacent when it comes to social distancing. Premier John Horgan announced that international travellers arriving in B.C. would be required to produce a 14-day self-isolation plan; otherwise they risked being placed in quarantine. Alberta Premier Jason Kenney also vowed to bring in stronger measures to screen international travellers at the border, even suggesting the use of smartphone apps to track them.
One thing researchers will be closely monitoring in coming weeks are the number of deaths in each province, Soucy said. Up until now, a lot of the deaths across Canada have involved vulnerable populations living in concentrated areas, such as nursing homes. In coming weeks, there will likely be a higher proportion of deaths from community cases, he said.
Those deaths may offer better insight as to which provincial health systems are doing a better job of keeping cases spread out versus those health systems that are being overwhelmed.
Douglas Quan is a Vancouver-based reporter for the Star. Follow him on Twitter: @dougquan