What’s behind the rise in coronavirus cases in B.C.?

British Columbia’s standing as Canada’s coronavirus success story appears to be on thin ice.

The number of daily cases in the province has jumped considerably in recent weeks, with 236 new cases recorded over a 72-hour period.

Such high numbers haven’t been seen in B.C. since April.

3:21 What B.C.’s August COVID-19 data shows public health officials

The upswing is drawing intense concern from both health officials and politicians, who warn that new enforcement measures are on the horizon. They’ve expressed fear that if B.C. continues on this trend, there will soon be more new cases of COVID-19 than at the pandemic’s previous peak.

But what’s behind the sudden spike?

Socializing and young people

The age group of new COVID-19 cases has shifted, not only in B.C. but across much of Canada.

In B.C., people between the ages of 20 and 29 now make up the group seeing the largest increase of infections, health officials say. People within 30 to 39 also make up a disproportionate number of the province’s infections.

2:08 Dr. Bonnie Henry explains possible long-term effects of COVID-19 on young people

Health Minister Adrian Dix and provincial health officers Dr. Bonnie Henry and Dr. Reka Gustafson have pointed to private indoor parties and expanded social bubbles as the biggest drivers of the rising case numbers.

“Water always finds the leak, sand always finds that gap, and COVID will find where it can go. Originally, it went to marginalized populations and nursing homes because that’s where it had an in,” said Colin Furness, an infection control epidemiologist and assistant professor at the University of Toronto.

“Now it’s gotten in among young people who are engaging in riskier behaviours.”

Despite the pleas from public health, the message to stop partying in large groups hasn’t been entirely respected. Over the Aug. 14-16 weekend, crowds gathered at an impromptu DJ event at Vancouver’s Granville Mall and flocked to Wreck Beach in masses.

While outdoor parties are frustrating, health officials said the “greatest danger” lies in large private indoor parties, which are also happening behind the scenes.

Just as the demographic has shifted, the focus of public health messaging needs to as well, said Dr. Isaac Bogoch, an infectious disease specialist based out of Toronto General Hospital.

“We really need a targeted public health intervention geared toward those in their 20s,” he said, adding that occupational risks might also be at play here.

“B.C. isn’t stupid, they’re cracking down. But a lot of this requires community buy-in. The community engagement you need is broad but also includes those in their 20s.”

But, as Furness notes, “house parties can’t necessarily explain the whole thing.”

2:03 Despite all the warnings, unsafe gatherings and parties continue in B.C.

Travel

All of Canada’s early coronavirus cases were travel-related.

In B.C., it was initially assumed that the province’s proximity to Asia and high volume of flights from China made it particularly vulnerable to the virus. But genomic analyses by the B.C. Ministry of Health later traced the province’s early cases to Washington State — which B.C. shares the U.S.-Canada border with — and a strain identified as “European-like and Eastern Canada.”

While Eastern Canada wasn’t defined as any specific province or city, Furness believes it was likely travellers coming from places like Ontario at the time.

The data from B.C.’s Provincial Health Services Authority shows whether cases are tied to international travel, but not domestic. However, more than a dozen domestic flights between Vancouver and cities like Toronto, Winnipeg and Calgary have been flagged as potential exposure sites since the beginning of August.

“Overall, these make up a relatively small proportion of infections in B.C.,” Gustafson told Global News. “We have no indication that current transmission in B.C. is significantly affected by interprovincial travel.”

But Furness said it’s possible the pattern could be repeating itself now.

“There’s already a pattern established here of cases coming from the east to Vancouver and making things worse,” Furness said. “That’s the baseline reality.”

The tricky part now is quantifying it, he said, adding that a “regulatory gap” might be a barrier.

Air operators are required to record the names of everyone on board an aircraft, but there is no federal requirement to submit passenger manifests to Transport Canada. The data often includes the names of travel agencies that booked flights, frequent flyer numbers, or the person who booked the ticket, but not necessarily the name and contact information of the person who actually flew on the plane.

B.C. ministers have recently put pressure on the federal government to make airlines provide more details to boost contact tracing efforts to no avail.

It’s possible this data is being collected by the provincial health unit, Furness said, but how much and to what quality is hard to say, especially if it’s not being released publicly.

2:17 Coronavirus: Air Canada cutting domestic routes

“If you’re in B.C. and you’ve got a whole list of cases and you ask the airlines how many of these people flew in from elsewhere in Canada, you can’t answer that question,” Furness said.

“It’s got to be happening. People don’t want to travel internationally and can’t travel to the U.S. right now. It’s just really hard to tell.”

The speed at which the province began reopening may have also made it tempting for travellers, Furness pointed out.

Cases dwindled the quickest in B.C., with daily case counts dropping to single digits in June. This fast-tracked the province to reopening indoor dining and bars.

The B.C. government does not require Canadian residents who have travelled to another Canadian province to undergo self-isolation.

“It probably feels safe to other Canadians because there’s not a lot of COVID,” Furness said. “But COVID moves with people, it doesn’t have its own wings. My position is all travel is a bad idea right now, and that might be what we’re seeing happen.”

What can other provinces learn?

We have to be “realistic” when looking at virus growth in any province, Bogoch and Furness agree.

It was about two months ago when B.C. moved to reopen its economy — faster than most other provinces. It’s possible what we’re seeing now is symptomatic of health protocols not being followed as provinces ease into that “new normal,” Furness explained.

“B.C. having very little prevalence of COVID meant they couldn’t get away with a lot, opening bars and other things. People started to say, ‘Look, B.C. did it and they didn’t see any upticks, Alberta did it and they didn’t see any upticks,” he said.

“But it’s going to take longer than two weeks to see the upticks. … Not every case results in more cases. It might be this two-month span where we actually see the results.”

2:27 Coronavirus: Toronto restaurants, bars reopen as city enters stage 3 of Ontario plan

Many recent cases in Canada have been linked to public places, and B.C. is no different.

The uptick in B.C. could very well unfold in other provinces as time passes, Bogoch added.

“It’s easy to point fingers,” he said.

“It doesn’t matter, the reasons why. As long as people are getting together in larger groups and indoor settings and are in close proximity to each other, it will result in a rise in cases, whether that be house parties, schools, factory settings, grocery stores, or restaurants.”

But “B.C. isn’t dealing with an uncontrolled spread right now,” Furness said.

“It will beg some questions about what’s not working, however.”

— with files from the Canadian Press