COLUMN: The other graph that shows B.C. can beat COVID-19

COLUMN: The other graph that shows B.C. can beat COVID-19

Is the curve being flattened? data on hospitalizations provides a crucial answer.

British Columbia’s curve has been flattening. Things are working. And yet doubters remain.

In times like this, what we need are – cue drumroll – more math and graphs, clearly.

You know, by now about The Curve. It’s a graph (has any emergency ever been more graphed than this one?) that depicts the number of COVID-19 cases in a certain jurisdiction. Those graphs are plotted on a logarithmic, rather than linear scale, to reflect how viruses move through a population at an exponential rate. When the line on the graph starts to flatten, that suggests that we are slowing the spread of the virus through our collective action. Such graphs are a good indicator of COVID-19’s spread, but they are not without their flaws.

And when an indicator has flaws, some people are going to suggest that those issues hide the fact that we’re all doomed and that the authorities are either oblivious to our impending doom, or covering it up.

We’re not doomed, and our health officials aren’t flying blind. We’ll get to the evidence later, but first let’s talk about the reason for some skepticism and the genuine trouble with that curve.

There is one key weakness with the famous curve graph: that it’s based on cases we know about, not the ones that we don’t.

British Columbia is testing people at a very high rate. But it’s not testing everyone. That’s left some people asking, day after day, why we aren’t testing more. And nearly every day provincial health officer Dr. Bonnie Henry appears before the media and explains why. There are a couple reasons, but the main one comes down to logistics: there’s no way at the moment to both reliably test and process the tests of everyone who has a scratchy cough.

There are manpower concerns, but also issues with false positives and false negatives and a rash of other challenges. Most medical tests give false results. It’s been suggested coronavirus tests are even less reliable. That presents a danger if people go to get tested, get a negative result, and then act as if they’re in the clear. Similarly, false positive results suck up resources as confirmation tests are made. Those are small challenges individually, but if you test even 10,000 people every day, all those false results can have a destabilizing effect.

Anyways, back to The Curve and the cases it reflects. If we believe that curve, B.C. is on the right trajectory. But to believe that curve, you have to believe that it’s an accurate reflection of COVID-19 cases in the province.

Now, you don’t have to think testing is capturing every single COVID-19 case, or even most such cases. But you do need to figure out if testing is capturing a relatively consistent snapshot of cases. The famous curve graph works if the number of known cases roughly tracks the number of unknown and known coronavirus cases from one day to another. If, on Day 1 we know about 50 per cent of all cases, and on Day 10 we know about 50 per cent of all cases it works. If on Day 10, we only know about 30 – or 70 – per cent of the actual cases, then the line will lie.

And therein seems to be the rub. We can’t know what we don’t know, right?

Well, let me tell you about hospitals. These are the places where sick people…. OK. You know about hospitals.

Well, let me tell you about the graph of COVID-19 patients in hospitals.

I’ve been tracking this statistic for a couple weeks now, and others have also cited it as likely the most reliable indicator of how things are progressing.

We might not know just how many cases exist, and we might not know whether testers are finding a greater, or lesser, proportion of the actual case load. But we know how many people have severe enough symptoms to require hospitalization.

And what we know is that the rate at which more COVID-19 patients are needing treatment in hospitals has been steadily decreasing. In other words, even as the number has risen, it’s risen at a slower rate.

(One caveat here is that hospitalization rates vary by age so the figures will vary a little depending on the ages of people spreading the virus. But, also crucially, while COVID-19 doesn’t kill young people very often, it does hospitalize them at quite a high rate.)

So, with all that prologue, you can see just a little below this a couple graphs (they may take a moment to load). On Friday, Dr. Henry announced that the number of COVID-19 patients in hospitals had gone down.

That’s the first time it has happened, but even discounting that day and by taking a seven-day average, one can see that even as the number of people in hospital has risen, the rate at which new patients are entering hospital has steadily decreased. This is how a curve gets flattened. If the rate increases, that’s very bad. If it stays the same, that’s also not great. It means more and more people are filling our hospitals.

But if that rate decreases, if it heads towards zero, that means humans – me, you and everyone else who is washing their hands and holing up inside – are winning. It means the rate of spread of COVID-19 is decreasing.

That does not mean that the spread of coronavirus has stopped. But it means there is hope. It’s not a reason to start holding house parties. Instead, it’s a reason to increase our vigilance. It’s a reason to punch this horrible virus in the face, and kick it while it’s down – metaphorically of course. If you’re close enough to punch a virus, you’re doing social distancing wrong.

COVID-19 hospitalizations in BC
Infogram

Do you have something to add to this story, or something else we should report on? Email:
tolsen@abbynews.com


@ty_olsen
Like us on Facebook and follow us on Twitter

Coronavirus

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

Interior Health update. File photo.
86 new COVID-19 cases, two more deaths in Interior Health

The new deaths are from Heritage Square, a long-term care facility in Vernon

(File Photo)
‘A lot of chaos’ around contact tracing in B.C.: Fernie Chamber of Commerce

Informal contact tracing efforts are causing local businesses to bear the brunt of rumour and hearsay

(File Photo)
Fernie Chamber to host virtual chat with business and physicians Jan. 18

The online conversation seeks to address issues including contact tracing in the community

The number of skiers and snowboarders using the Fernie ski shuttle to get to Fernie Alpine Resort from town is down by 77 per cent this season. (Scott Tibballs / The Free Press)
Shuttle use down 77 per cent as travel advisory bites

The ski shuttle in Fernie is reducing it’s frequency to five times a day as a result

A photo from an early construction stage taken in the fall of 2020. (Photo Contributed)
Elkford’s Meeting Place comes to life

Construction on the outdoor space is set to wrap up this coming summer

Health Minister Adrian Dix and provincial health officer Dr. Bonnie Henry head for the press theatre at the B.C. legislature for an update on COVID-19, Jan. 7, 2021. (B.C. government)
B.C.’s COVID-19 spread steady with 509 new cases Friday

Hospitalized and critical care cases decline, nine deaths

A COVID-19 outbreak at Vernon's Heritage Square long-term care home has claimed seven people. (Jennifer Smith - Morning Star)
Two more COVID-19 deaths at Vernon care home

Heritage Square has now lost seven people due to the outbreak

Chief public health officer Dr. Theresa Tam provides an update on the COVID-19 pandemic in Ottawa on Friday, Jan. 8, 2021. THE CANADIAN PRESS/Sean Kilpatrick
Canada’s top doctor says to avoid non-essential travel as B.C. explores legal options

Premier John Horgan says he is seeking legal advice on whether it can limit interprovincial travel

Seasonal influenza vaccine is administered starting each fall in B.C. and around the world. (Langley Advance Times)
After 30,000 tests, influenza nowhere to be found in B.C.

COVID-19 precautions have eliminated seasonal infection

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

Martin Luther King Jr. addresses the crowd during the march on Washington, D.C., in August of 1963. Courtesy photo
Government reinforces importance of anti-racism act on Black Shirt Day

B.C. Ministers say education “a powerful tool” in the fight for equity and equality

Andre Robert won $500,000 through a Lotto Extra ticket on Dec. 23, 2020. Photo: Jeanne d’Arc Allard
Creston resident wins $500k through Lotto ticket

“I was surprised. I wasn’t sure if it was true or not.”

Jobs Minister Ravi Kahlon shared a handwritten note his son received on Jan. 13, 2021. (Ravi Kahlon/Twitter)
Proud dad moment: B.C. minister’s son, 10, receives handwritten note for act of kindness

North Delta MLA took to Twitter to share a letter his son received from a new kid at school

Purcell Wilderness Conservancy expanded with 18 hectares of previously privately-owned land. Photo from BC Parks.
Purcell Wilderness Conservancy expanded following Provincial land acquisition

18 hectares of waterfront added to critical wildlife habitat

Most Read