A coronavirus testing laboratory in Leeds, UK (Credit: HM Treasury)
Some doctors say we must test widely to find all carriers of the coronavirus. British Columbia isn’t doing that.
ON MARCH 16, as many countries rapidly expanded their social-distancing measures to combat spread of the SARS-CoV-2 coronavirus and the associated disease COVID-19, the director-general of the World Health Organization told them that they needed to do more.
“The most effective way to prevent infections and save lives is breaking the chains of transmission. And to do that, you must test and isolate,” said Dr. Tedros Adhanom Ghebreyesus. “You cannot fight a fire blindfolded. And we cannot stop this pandemic if we don’t know who is infected. We have a simple message for all countries: test, test, test. Test every suspected case.”
Canada generally, and British Columbia in particular, claims to be following that advice. B.C. health minister Adrian Dix says the province conducts around 3,500 tests for COVID-19 every day. According to the B.C. Centre for Disease Control, by March 31 the province had conducted 43,229 tests — 8,458 per million residents, a testing rate better than the 8,152 per million conducted by South Korea, considered a model country for managing the crisis.
But some say that’s still not enough if we want accurate data about the prevalence of the virus, and hope to identify and isolate carriers who are only experiencing mild symptoms, or no symptoms at all.
Estimates of the number of such asymptomatic carriers varies greatly. One study of the notorious Diamond Princess cruise ship found that half of its passengers who tested positive for COVID-19 showed no symptoms. A recent study of transmission of the virus in China said that 86% of the infections there went undocumented — meaning that for every one person who tested positive, another six carried the virus but weren’t identified. “This high proportion of undocumented infections, many of whom were likely not severely symptomatic, appears to have facilitated the rapid spread of the virus throughout China,” the researchers said.
Consequently, some argue that the only way to catch those asymptomatic carriers is to test healthy as well as sick people, like Iceland has done. As of April 1, Iceland had conducted 19,516 tests of its 364,000 citizens, or 5.3% of its population, the highest testing rate in the world. “The virus had a much, much wider spread in the community than we would have assumed, based on the screening of high-risk people,” said Kári Stefánsson, a neurologist and head of the Reykjavik-based biopharmaceutical company deCode genetics. Iceland has identified 63 positive cases for every 1,000 tests, a rate of 6.3%. British Columbia, on the other hand, has only turned up 23 positives for every 1,000 tests.
Dr. Bonnie Henry, B.C.’s provincial health officer, told FOCUS at a March 28 press conference that the province is testing some asymptomatic people — if it’s tracking the source of an outbreak, for example — but otherwise it’s concentrating tests on workers in the health-care system and long-term care homes, and people being admitted to hospital, to ensure that COVID-19 sufferers are separated from other patients. “A broad testing of well people in our community right now is not what we are going to be doing,” she said. “That is the strategy we will be looking at if and when we come to the downside of our curve, when we’re looking again at introductions coming into B.C. from other places. That’s part of the strategy that would be at that phase of the epidemic. But certainly not right now.”
What’s more troubling is the fact that B.C.’s testing regime is also bypassing people who are showing symptoms of COVID-19. On March 23, the CBC reported that at least 11 attendees at a memorial service in Vancouver were experiencing symptoms, and though some were told by doctors that they likely had the virus, they still didn't qualify for testing.
On March 28, Dr. Sean Wormsbecker, an emergency-room physician at New Westminster’s Royal Columbia hospital, posted a video (embedded below) expressing his frustration that “based on our current resources, we are very much undertesting the population.” He said he saw several ill patients that day who likely had COVID-19, but because they displayed stable lung function, he followed the Ministry of Health’s protocol and sent them home without testing. “And that scares me,” Wormsbecker said, concerned that such patients wouldn’t self-isolate because they didn’t know that they had the virus. He also said failure to test those patients means B.C. is “low-balling” its numbers, and that we’re not copying the nations that have identified carriers to flatten their rates of infection. “We can’t use those countries like Singapore or [South] Korea as a benchmark for what we can expect to come.”
“I actually don’t agree with that,” Henry said on March 30, when asked about Wormsbecker’s comments. “Having been on the front lines with my colleagues in public health who are actually talking to these people, who are at home and who are self-isolating, most people are absolutely doing what we need them to do.” As she explained, the province’s testing strategy has been to concentrate on the people most likely to have the disease, and those most likely to need hospital care. “And we are still maintaining the contact tracing, we’re talking with people who have this, who have mild enough illness that they’re able to stay at home. For the most part, that is working.”
Strategy aside, the province is also likely limiting tests to conserve its supplies for the peak of the crisis. (FOCUS asked the Ministry of Health what’s holding up wider-scale testing, but the Ministry hasn’t replied.) Governments around the world are in a rush — and sometimes bidding wars — for the nasal swabs and chemical reagents used in test kits, and for PPE (personal protective equipment) such as gowns and masks, which if used for testing would take them away from hospital wards. It’s true that some countries like South Korea and the United Arab Emirates have been able to conduct large-scale testing, but that’s because they’ve been stockpiling equipment and chemicals ever since the MERS coronavirus hit them in 2015.
Instead, it seems that locating those who actually have the virus in B.C. will be left up to a variety of ad-hoc projects. The City of Langford, for example, has created its own COVID-19 response team, asking all of its residents to take an online screening test, even if they don’t have symptoms, to “help us understand the COVID-19 health status of our community.” Langford mayor Stew Young told CFAX that the team has already sent doctors to the residences of 16 people for in-home testing, using a small number of test kits provided by the province. “What's going to win the war is test kits and home testing at the front line and keeping our hospitals for the severe cases,” Young said. “That is the way to do this.” (Dr. Henry doesn’t agree: when asked about Langford’s project on March 31, she said “it’s not a good use of resources to test people who are at low risk.”)
Online projects are also springing up to assess local COVID-19 risks, such as FLATTEN, which asks Canadians to answer an anonymous online survey about their symptoms and contacts with COVID-19 patients, generating a “heat map” of the country organized by postal code. By March 31, 281 people had answered surveys in the V8V postal code, which covers James Bay and Fairfield — and 24 of them exhibited enough symptoms and/or connections to be considered “potential cases,” suggesting the spread of the illness could be wider than officially declared, even in Victoria.
We won’t know without tests. New ones should be coming quickly: on March 27 the US government approved a new test that can provide results in minutes, unlike current tests which take days, and the manufacturer plans to start cranking out 50,000 of them daily.
In the meantime, British Columbia, like the rest of North America, is about to head into the mouth of the COVID-19 storm. Very soon, we will know whether or not the province’s testing strategy has worked.
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