B.C.'s new COVID-19 reporting system could miss many deaths among younger people, scientist says
People who die more than a month after testing positive not included in weekly tallies
B.C.'s switch to weekly reporting of COVID-19 data also comes with a notable change in how deaths are recorded, which one expert says could have some counterintuitive consequences.
The new reports include everyone who died within 30 days of testing positive for the novel coronavirus, whether or not COVID-19 has been confirmed as an underlying cause of death. Previously, each death was reviewed to determine if it was a result of the virus.
But while this means anyone who tests positive and then dies in a car crash three weeks later will be counted, for example, it doesn't necessarily mean the COVID-19 numbers will be inflated.
According to Tara Moriarty, an associate professor and infectious disease researcher at the University of Toronto, many deaths directly caused by COVID-19 will instead be missed, particularly among younger people who are more likely to be treated longer in hospital.
"It trims the number of younger COVID deaths especially, because people who might be in ICU or hospitalized for a long period of time tend to be younger because they're more likely to survive for longer," Moriarty said.
Moriarty, co-founder of COVID-19 Resources Canada, has long argued that B.C. and other provinces are significantly undercounting the number of COVID-related deaths.
She said B.C. is not alone in moving to this new method for counting deaths, but she sees no scientific reason for the change. As she points out, some patients with long-haul COVID-19 can live for months before dying from the disease, but those deaths won't be included in the new weekly reports.
Useful metrics still available
The B.C. health ministry has said the new weekly reports signal a shift from a "case-management" approach to the pandemic to a "surveillance" method, similar to how infectious diseases like influenza are monitored.
Overall, Moriarty and other researchers following the data don't see major issues in switching from reporting numbers every weekday to doing it weekly.
"The problem is when there starts being really rapid changes, when there's a fast moving wave," Moriarty said.
"It's difficult at times like that to know what's happening."
Caroline Colijn, a COVID-19 modeller and Canada 150 research chair in the mathematics department at Simon Fraser University, said the switch to weekly reporting could potentially free up resources for public health staff to compile new information to help B.C. better understand the pandemic.
For members of the public, she recommends watching trend lines for cases rather than absolute numbers to gauge whether things are getting better or worse. Even though B.C.'s testing capacity has been drastically reduced since Omicron hit the province, Colijn says there is value in knowing the direction the numbers are heading.
"We have always underestimated the number of cases," she pointed out.
Moriarty said other useful measures include wastewater testing data and the test positivity rate.
Provincial Health Officer Dr. Bonnie Henry has said anything above a five per cent test-positivity rate is an indicator of a more worrying level of transmission.
Right now, the rates have started trending upward again as the sixth wave looks set to strike, hitting about seven per cent provincewide and as high as 17 per cent on Vancouver Island.
'Evolution hasn't gone away'
Still, as provinces like B.C. scale back on COVID-19 reporting, some of those who are most vulnerable to the disease are feeling abandoned.
Moriarty's organization holds public Zoom sessions every Tuesday and Wednesday evening to talk about the latest COVID-19 information research. She said recently a lot of older and disabled people have been expressing deep fear and distrust of health officials.
In an attempt to fill the data gap, COVID-19 Resources Canada, which receives funding from the Public Health Agency of Canada, is developing a tool that would help regular people assess the risk in their communities.
Moriarty compares it to a wildfire hazard graphic, and said it should roll out in the next few days.
Colijn warns that with elevated levels of the virus still circulating around the world, there's a strong chance of a new variant evolving that could raise everyone's risk significantly, no matter what way the data is trending.
"Evolution hasn't gone away," she said. "The more virus you have out there, the quicker evolution happens."