Not everyone can be tested for coronavirus, nor should they be

As the number of coronavirus cases climbs, and anxiety rises even faster, everyone is clamouring for more new coronavirus testing.

But let’s be clear: Not everyone can, will or should be tested.

The number of tests is not unlimited, nor is Canada’s laboratory capacity.

We have to focus testing on high-risk groups, meaning those who are most likely to spread the coronavirus to others and those most likely to suffer the greatest harm.

Currently, that includes five broad categories:

• Travellers who have returned to Canada and now have symptoms of COVID-19 (notably dry cough and fever), and their direct contacts with symptoms;
• People with severe respiratory illness such as pneumonia, regardless of whether they have left the country or not;
• People in institutional care – nursing homes, long-term care, hospitals – who show symptoms;
• People living in remote First Nations communities who have symptoms;
• Any health-care workers who are sick with respiratory symptoms;

We also need to do some random testing, especially in high-risk settings such as nursing homes and hospitals.

The provinces have to be a lot clearer about the guidelines, for the sake of the public and health providers. The situation is fluid, so testing rules will change.

There’s really no reason to have different standards in every province. All that does is create confusion.

What we can’t do right now is test everyone with mild symptoms, or everyone who is simply worried.

Triage may seem cruel, but triage is essential, especially during a pandemic. We can’t waste scarce resources mollifying the worried well or the slightly unwell.

Canada has, to date, done about 34,000 coronavirus tests, about 1,000 per million population. It started slowly but has really picked up in recent days.

The U.S. has done only 37,000 tests, about 100 per million population. Its response is widely viewed as a debacle and quite possibly an Italy-like disaster in the making.

South Korea, which has set the global standard, has done in excess of 275,000 tests, more than 5,000 per million population.

In a perfect world – one where, among other things, public health doesn’t merely get crumbs of the health budget – we could put surveillance on steroids and swab everyone who wants it, and then some, just like South Korea.

We can still get there. Commercial tests are being developed and that will increase the supply. And public health is starting to get in gear, particularly in provinces where there is virtually no testing.

In the interim, we all have to do our part – which is a refrain you’re going to hear a lot in the coming weeks, related to social distancing, and to widespread shutting of public venues and services.

On the testing front, we need Canadians to lessen the burden on the overtaxed testing infrastructure. That means embracing self-assessment.

Several provinces have self-assessment tools, online quizzes that help determine if you should seek testing. One of the best is from Alberta Health Services. With a few quick questions, you will get a sense of whether you need to call 9-1-1 (a health emergency), 8-1-1 (which will guide you to a testing site), or simply sit back, like you would with a cold or mild flu.

There is a lot of whining about 8-1-1 and other provincial telemedicine lines. But, despite adding a lot of staff, they are overwhelmed and can take hours, even days, to get back to people.

The practical result of limited testing is that we’re going to miss cases. As a result, the coronavirus will spread more widely.

That’s not ideal, but it’s the current reality.

What public-health officials need to do is be a lot clearer about the fact that community spread is now happening on a significant scale.

For weeks, Canada took comfort in the belief that all coronavirus cases were being imported by travellers. We know now that at least 20 per cent of known cases are community-acquired.

Developments in recent days, like the news that several people were infected at a dental conference in Vancouver, and that at least seven people contracted COVID-19 at a single event in Alberta, are strong hints that there are likely thousands of undetected cases.

Vera Etches, the city of Ottawa’s medical officer of health, said there are likely between 200 and 1,000 undetected cases in that city alone.

Good communication is paramount, so we could use more of that candor.

“No test? Don’t fret” is also a message that needs to be conveyed clearly and widely.

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