Covid-19: Our under-testing problem and why the solution is asymmetry

Alwyn Lau

31 May 2020 at 6:54 pm·4-min read

JUNE 1 ― Recently, the daily number of confirmed Covid-19 cases have been moving so erratically it’s like they were playing dodgy hide-and-seek with us.

For two or three weeks it hovers around moderate to high double-digits (“I’m here!”), then it suddenly jumps (“No, I could be there!”) then it falls to almost single-digits (“But instead I’m nowhere!”).

Malaysians could be forgiven for feeling both confused and “safer” at the same time.

Every day, thousands of folks wait with bated breath around 5pm to get those numbers, yet we hardly know what to think when those figures appear: If it’s low, do we feel like we’ve achieved something? If it’s high, what does that “mean” for the low numbers? Are the numbers an accurate reflection of the situation in the first place?

Some of us, on account of the more regular “low” numbers, probably think that we have already “beaten” Covid-19 and it should just be a matter of time before schools, cinemas and even reflexology centers reopen.

This would be a mistake. For two reasons, one is obvious (testing) and another not-so-obvious (asymmetry).

Let’s do the obvious one first.

1 ― Under-testing as problem (or seeing only where the flashlight points)

Fact: Our testing rate is pretty low. We are doing about 3,000-4,000 fewer tests per million people than countries like South Korea.

Due to limited testing kits, plus the initial strategy of focusing on “red zone” areas or high-priority patients, our country has limited the scope of our Covid-19 tests.

While this line of action is understandable, it’s obvious that — almost by definition — our country’s testing is inadequate.

And this inadequacy throws into question any talk of certainty, “approximate accuracy” and so on.

Imagine a guy being told that there are snakes in his backyard. He tries to look for them at night, there are no lights, the only thing he has is a flashlight (with a weak battery).

As a result, he decides to shine the light on only selected parts of his yard (duh). Even assuming he finds one or two snakes, can he conclude that his search is adequate, let alone that “there are no more snakes”?

I mean, the obvious problem is that he simply hasn’t shone his flashlight at the majority areas of his yard; there is no basis to conclude anything about his search, let alone that it’s now safe for his kids to play in.

Ditto, Malaysia. We only see where the (weakly-powered) “flashlight” is pointing at, and are clueless about those sections of the population not illuminated. Whatever our numbers, we are certainly under-estimating our positive cases by quite a bit.

Do note that I am not saying there is a “conspiracy” to sugar-coat our numbers. In fact, not at all. I believe the numbers simply reflect the limits created by the availability of our testing kits, and the burden of proof should be on anyone who claims deliberate manipulation.

2 ― Asymmetry as solution (or why the spikes are more important that the drops)

When the daily numbers go high, it’s valid for you to feel concerned. But when they drop you should not feel safer. This is because high-danger situations always warrant an asymmetric response.

Eg, if the doctor says your elderly loved one may have a chronic illness, the responsible thing to do is focus on her negative symptoms, not on those times she says she’s okay lah, nothing to worry about, I’m fine lah, etc. That’s asymmetry: When health is threatened, signs of sickness are more important than reports of non-sickness..

Applying this to our daily numbers (and bearing in mind our low testing rate), the correct way to “read” our numbers is to give more weightage to the spikes than the drop-offs.

The fact that on two days straight last week the numbers almost touched 200 should be worth more attention than the fact that they have been double-digits regularly.

We simply don’t know what the “true” numbers are ― so let’s be cautious. We simply don’t know the “true” severity of the virus on children, young adults, etc ― so let’s be cautious.

We simply don’t know who in our community does or doesn’t have the virus – so let’s be cautious.

Until there’s a vaccine or an effective treatment, folks, nothing has really changed since March. The virus is still out there and its spread remains an unknown. Let’s not make things worse by presuming we’ve mastered it.

Remember, a) we’ve only pointed the flashlight in one area and b) we haven’t caught the great white shark yet, so best not to open the beach because we think it “looks safe.”

* This is the personal opinion of the columnist.