The plexiglass barrier problem

Justin Ling: Vaccines, masks and ventilation are working. So why do governments keep doubling-down on the measures that don’t effectively stop COVID?

A grocery store worker clean a work space and plexiglass divider in downtown Vancouver on April 29, 2020 (Jonathan Hayward/CP)

A grocery store worker clean a work space and plexiglass divider in downtown Vancouver on April 29, 2020 (Jonathan Hayward/CP)

You open the door and prepare to step outside when a pang of guilt hits, as though leaving the house is an act of transgression in and of itself.

You go to the grocery store: One employee in a face shield gestures towards a jug of hand sanitizer, while another at the cash register furiously wipes down the conveyor belt. You grip onto the shopping cart, still slimy from the disinfectant, and follow the peeling arrows taped to the floor.

Later, you head to the gym: Half the machines are still out of commission, covered in signs that say: CLOSED, TO ENABLE SOCIAL DISTANCING. A similar sign hangs on the water fountain, same for half the lockers in the locker room. The hairdryers are gone, ostensibly for the same reason.

You take the bus to meet some friends for lunch: You pick the rare seat that isn’t taped off TO ENABLE SOCIAL DISTANCING. You settle at a table, peering through the plexiglass barriers which surround you, waiting for your friend to walk through the doors. Off in the corner, a karaoke machine looks covered in cobwebs, memory of a bygone era. Your favourite song comes on: It’s your song. The beat moves you and you stand up to start moving your hips. A kindly manager beelines to your seat, putting a firm hand on your shoulder and forcing you back into your seat. No dancing.

READ: First it took his mom. Then his dad. Then, finally, him. The story of a family stolen by COVID-19.

Your doctor still isn’t seeing patients in-person. You need to make a reservation to renew your passport. Every time you touch a pen at the bank, the cashier throws it in the nearest garbage. Leaving the country can mean no fewer than three nasal swabs: Tests that make you $200 poorer. Your hands have been dry and cracking for a year-and-a-half.

Some, or all of it, probably sounds exhaustingly familiar. Daily life in the late pandemic is made up of a series of rituals that once felt comforting, but which now feel rote — maybe even downright absurd.

It’s well past time that our governments and public health officers start navigating a way out of this pandemic with policies and advice to the public that actually follow the science, instead of relying on superstition.

First, the science.

It took some time, but we now know — and have known for a while, with a really high degree of certainty — that COVID-19 is predominantly transmitted through aerosolized particles.

We, of course, initially believed that the virus was transmitted mostly, if not exclusively, via droplets. We were told that the main risks came from catching those droplets in our mouth or nose, or by fomite transmission: Touching the same surface as a sick person and transferring the droplets to our respiratory system. That initial belief was well-intentioned, but mistaken.
A pile of research has shown that surface transmission is somewhere between unlikely to near impossible. A recent study in hamsters found COVID-19 was significantly less infectious and serious when passed-on by touching surfaces. Last August, microbiologist Emanuel Goldman reviewed the available literature and concluded that “the chance of transmission through inanimate surfaces is very small, and only in instances where an infected person coughs or sneezes on the surface, and someone else touches that surface soon after the cough or sneeze.”

Coming around to this error meant we could stop sanitizing our groceries and wiping down letters — most of us did, anyway.

We actually know why such a mistake was made: It involves a half-century-old math error that told epidemiologists COVID-19 was too big to float through the air. Correcting that error meant realizing that the virus particles don’t fall as soon as they leave our mouth or nose, but they can in fact float and travel some distances. 

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It’s a reality that some governments and public health figures in Canada have been loath to acknowledge, as I wrote with some frustration last April. Things have only gotten marginally better since. The Public Health Agency of Canada now recognizes that COVID-19 is transmitted “through respiratory droplets and aerosols,” and recommends good ventilation in indoor settings. But, at the same time, the agency says the virus can also be passed by “touching something that has the virus on it, then touching your mouth, nose or eyes with unwashed hands.” 

There is overwhelming evidence that airborne transmission is the dominant cause for COVID-19 outbreaks. We still don’t know how often people get sick from touching their eyes: All we know is that it is orders of magnitude less likely than contracting it through the air. Putting both explanations side-by-side gives the completely incorrect perception that they are equally likely.

But look through the Public Health Agency of Canada’s advice for Canadians to beat the virus, and it’s totally divorced from that reality.

The guidance recommends that “high-touch surfaces and objects such as toilets, bedside tables, light switches, door handles, and children’s toys should be first cleaned (to physically remove dirt) and then disinfected frequently.” Which is about as an effective use of your time as nailing a horseshoe over your door frame.

That advice also conjures fear about public buses and subways, warning that “certain populations are more likely to rely on public transportation and therefore may have increased risk of exposure.”

No country has established any considerable link between public transit and COVID-19 transmission. France has meticulously tracked outbreaks, and has consistently found none tied to its beloved transit system. A Public Health Ontario meta-analysis of the available research found a handful of studies, mostly from early in the pandemic, found no clear evidence that public transportation was responsible for a significant spread of COVID-19. One particularly interesting case saw a third of the riders on one bus in Zhejiang province, China, test positive for COVID-19 — but proximity to the person likely responsible for the outbreak only corresponded to a slightly higher risk of contracting the virus. That means the culprit was likely the recirculating air on the bus, not because it wasn’t scrubbed enough.

More recently, the Public Health Agency has put out a guidance on indoor filtration which, crucially, includes a recommendation for HEPA filters — simple, cheap filters which can be deployed in large buildings, or in your home and which we know actually captures COVID-19 particles in the air. But the confusion still reigns: Are Canadians supposed to infer that air filtration is more, or less, important than scrubbing your kid’s teddybear with bleach?

I was chatting, recently, with someone inside the government on the COVID-19 file. Why not drop all this nonsense about surface transmission? I asked. They sighed, explaining the attitude inside government: Going harder on the reality of airborne transmission would mean acknowledging that the incessant reminders around handwashing and face-touching — while relatively good advice in a normal flu season — were ineffective in fighting this pandemic. People will feel lied to. Trust will plummet.

What’s not working

Government regulation and funding continues to disproportionately back these unscientific solutions to the pandemic.

When I asked the Government of Canada how much support they allocated to actually funding good ventilation, Infrastructure Canada pointed to a $150 million pot of money, announced in April, to install new ventilation systems in hospitals, schools, public buildings, and in First Nations communities. That’s good! But the Government of Canada has spent more than twice as much on hand sanitizer. CBC found Ottawa spent nearly $1 billion per day throughout the pandemic. Every level of government should have prioritized better airflow and improved filtration more than a year ago. They didn’t.

The massive spending on PPE, to the tune of some $6 billion, came after Canada was woefully ill-equipped in crucial masks, gowns, and other gear necessary for health care and frontline workers. Since then, however, PPE requirements have remained essentially constant — COVID-19 patients in hospitals are still being put in droplet isolation, meaning patients and health-care workers are generally required to wear gowns, gloves, masks, and face shields. The sheer cost to constantly replace that PPE is staggering. Even if money should be no object, money is not infinite. Prioritizing where those dollars go, especially two years into this crisis, is important.

READ: Will Canadians need COVID booster shots?

Let’s talk about those plentiful plexiglass barriers which line bars, restaurants, and shops for a second: They are monument to the idea that tiny viral droplets and fomite transmission are the reason for the pandemic. Governments have required them in spaces where people cannot space two meters apart. In practise, however, that outdated way of thinking may be making things worse.

In one British study, researchers modelled what role, exactly, these barriers were playing: They found that screens could block larger droplets when two people are face-to-face—we don’t necessarily need modelling to figure that out. But, more crucially, they found that these screens and barriers could “increase risks of aerosol transmission due to blocking/changing airflow patterns or creating zones of poor air circulation behind screens.” In other words: We’ve prioritized the risk of droplet transmission over aerosol transmission, yet again.

Then there’s the constant cleaning and hand sanitizing. It feels like every surface in the world, from our hands to countertops, rental car steering wheels, and door knobs, are being constantly sanitized. 

This comes with a cost. Put aside the environmental impact of all this cleaning waste, we’re actually destroying public infrastructure.

In Toronto, the TTC spent an additional $12 million in cleaning during 2020, and requested an additional $15 million for 2021. But that’s not all: “The corrosive nature of the approved products has resulted in corrosion and damage to vehicle surface and equipment,” the TTC’s Chief Vehicles Officer wrote in September. The incessant cleaning and sanitizing of busses is also leading to huge costs and delays for commuters in Toronto: That, in turn, can worsen crowding. 

Throughout the pandemic, the rank incompetence of many of our provincial governments has led to a doubling-down on these rules when things go bad. When the decisions of François Legault, Jason Kenney, or Doug Ford have led to an explosion of cases, they have screeched at us about hand-washing and shut down services which had never been particularly risky — the appearance of action has consistently trumped the efficacy of that action. As I wrote last month, this should make us really angry.

But it doesn’t have to be this way.

What does work

We are not in the midst of the worst pandemic in a century because people keep swapping sneezes. We are here because entire rooms full of people can fall ill: The dreaded superspreader events. Those mass infections occur when the prevalence of the virus in the air grows to such a point that merely breathing in is risky. The way to beat that, we know, is to exchange and—ideally—filter the air. Wearing masks, which seem to decrease the amount of viral particles we inhale and exhale, is a great mitigation measure.

One study of American schools, published in Science, found mandatory masking to be hands-down the most effective strategy for reducing COVID-19 spread. Closing the cafeteria, desk shields, closing the playground: These strategies corresponded to a higher rate of cases.

Researchers in New York, in July, published a study looking at transmission in exercise classes. “We report no known viral spread when masks, social distancing, and HEPA ventilation were utilized in a high intensity exercising environment with shouting/loudness of vocalization, which is associated with rapid spread of COVID-19.”

Another study, in Brazil, surveyed people on mask usage and social distancing and found “adults who reported moderate or greater adherence to distancing recommendations reduced their odds of infection by one half to two thirds, and those who reported using masks when out reduced their risk by 87 percent.”

All three studies involved people who had not yet been vaccinated.

Mass vaccination, and limiting access to higher-risk settings strictly to those who are fully vaccinated, is clearly one of the most effective strategies we have right now. Even if a vaccinated person has a breakthrough case of COVID-19, the prevalence of the virus in their system is likely to be low, which means the volume of viral particles they’re breathing into the air will be low. That means that it is even less likely that someone else in the room, who is also vaccinated, will get sick — if they do, it will almost certainly be an even-more mild case, which in turn makes their case less infectious.

But even since the mass vaccination campaign, it’s become clear that we still need to keep a few core strategies. On July 30, New Brunswick — one of the most vaccinated parts of the country — dropped its indoor mask mandate. Starting in early August, the province began seeing an alarming rise in cases, adding nearly 100 cases per day by the end of September, the worst period of the pandemic yet for the province. Since August, 68 people have died, and things are still getting worse. (The overwhelming majority of cases, serious illnesses, and deaths are of unvaccinated people.)

Next door, in still-masked Nova Scotia, the fall has seen a tiny blip in new cases. There have been just seven COVID-19 deaths since August.

It’s hard to say with any absolute certainty that masks—even run-of-the-mill cloth ones—are the difference-maker in terms of new COVID-19 cases. States are complex systems and isolating variables is famously difficult. But the compelling evidence definitely suggests there’s a causal effect between good indoor mask usage and fewer cases.

Widely-available rapid testing can shrink the risk even further by catching outbreaks and break-through cases. Yet good luck finding one: The rarity of rapid testing Canada has been an unspeakable boondoggle. In America, anyone can buy a two-pack of effective and accurate COVID-19 tests for $20. In Canada, trying to track down a rapid test is like trapping a rare butterfly.

If we can keep up mask-wearing, expand vaccination, deploy rapid testing, and improve ventilation, cases are going to continue falling. Focusing on those core, effective, strategies means we can get back to doing regular things: Like dancing. Like karaoke. 

And, eventually, we won’t have to wear masks at all.

A sunk cost fallacy

I asked Andrew Morris—a professor of medicine, an expert in antimicrobial stewardship, and a member of Ontario’s Science Table—his thoughts on what’s working, and what’s not.

For starters, Morris says promoting vaccines needs to remain “numero uno.” When it comes to addressing transmission, he says the priorities are clear: Masking, ventilation and filtration, rapid tests, and better flexibility for working and schooling including sick pay.

It’s time, Morris told me, to “get rid of low-value stuff.” That means we need to “de-emphasize cleaning, physical barriers, hand hygiene.” These things may help, he notes, but not nearly as much as the clear strategies that we know, scientifically, are effective. 

There are those, including in public health roles across the country, who would argue that we must continue the incessant hand-washing and putting up plexiglass barriers out of an abundance of caution.

But that’s not science. Science asks us to test — and to pursue what works, and drop what doesn’t. In effect, what governments across this country are asking us to do is to invest faith in these strategies. If cases go up, it’s because we’re not washing our hands well enough. If cases go down, it’s because we’re washing our hands more.

This isn’t science. It’s not even pandemic theatre. It’s superstition. And it’s not harmless.

“It diverts energy from other higher yield interventions,” Morris says. It can also muddy something that we have sorely lacked for the past two years: Clear messaging. Morris advising the public can be as simple as “stay home if sick, breath clean air — and wear a high-quality mask if you can’t.”

We do not have that clarity. 

What’s more, we are risking COVID-19 fatigue. Rather than focusing on strategies that work, and ditching ones that don’t, we are just stacking advice to the ceiling. Regular people no longer have a sense of what’s effective, and what’s useless. Some still wear masks outside. Others are still pressure washing their groceries. Some think face shields are more effective than masks. (They are not.)

We’ve had a truly miserable two years. But it hasn’t been for naught: We know what works. We know what doesn’t. The more we can ditch the latter and focus on the former, the sooner we can leave Footloose rules, stop slathering our poor hands in harsh chemicals, and end the constant brain-poking.