Deep cleaning surfaces: Does that protect people from COVID-19?

Hosted by

Workers sanitize conveyor belts after every single transaction to maintain cleanliness for shoppers at the Pay-Less Supermarket store in Dededo. Aug. 19, 2020. Credit: Rick Cruz/PDN via Imagn Content Services, LLC.

A lot of businesses are trying to lure people back by hyping intense deep cleaning policies. Gyms are scrubbing down equipment between each use. Grocery stores are wiping down card readers, carts, and even checkout conveyor belts between each customer. Restaurants are cloroxing booths between diners. 

The Atlantic writer Derek Thompson calls all this cleaning “hygiene theater” because surface transmission is actually quite rare.

KCRW: Is this all performance?

Derek Thompson: “It’s not just performance, but it's definitely mostly performance. There are some diseases that are predominantly transmitted by touch. This is not one of them. 

… It seems to spread from our breath from sneezes, from coughs, through large droplets transmitted, through aerosolized droplets, or tiny tiny little droplets that sort of linger in the air like a spray that comes from just talking in an unventilated indoor environment. 

… We should be worried about being in an unventilated indoor space without our masks for a long period of time. That's when the disease seems to be most dangerous. 

But when you look at outdoor environments, it seems to be less dangerous. 

And when you look at surface transmission, it just doesn't seem to be particularly common. So I think the problem is not so much that people are washing their hands. They should of course continue to wash their hands, it’s a pandemic. But they maybe shouldn't obsess so much over the surface transmission of a disease that is spreading predominantly through the air.”

A lot of us are wiping down packages that we receive from Amazon, for example, because what if the delivery person sneezed on their hand and then touched the package and then left it at the door? Should I wipe down the package just in case?

“I have no problem with people washing their hands vigorously or wiping down packages if that's what makes them feel better. 

My biggest problem is reserved not for individuals, but for companies. The problem is that you have lots of companies, restaurants and bars that are spending lots of money on wiping down all of these surfaces, and then inviting a bunch of patrons to enter a dark unventilated indoor space where they're likely to transmit the disease through the air. 

So they're essentially performing hygiene theater. That is having the purpose of putting people in more dangerous situations.

… Restaurants like Applebee's saying, ‘Of course, it's fine if you dine in one of our establishments because we're constantly wiping down the tables.’

Well, people aren't typically getting sick from touching tables, which in a normal restaurant are getting wiped down anyway. They're getting sick from breathing without a mask close to other diners who themselves are breathing and shouting and potentially exhaling disease droplets.”

What do the studies say exactly about surface transmission? Has there ever been a case where someone has gotten coronavirus from a surface? 

“It's very hard to say because there are tens of millions, maybe hundreds of millions of people around the world that have contracted COVID-19. And we can't say exactly how all several hundred million of them got it. 

That said, there's been a lot of contact tracing research. And in very few studies, do we have really clear smoking gun evidence of surface transmission? I spoke to one researcher who published a note in The Lancet, the medical journal, who said in reviewing a lot of these studies that he found practically no evidence that surface transmission had ever happened or had ever been proven in these contact tracing studies. 

So I don't want to give 100% confidence that surface transmission has never happened. But you know, sometimes people say absence of evidence is not evidence of absence. That's absolutely true. 

But I would say that extreme infrequency of evidence is probably evidence of extreme frequency. It just does not seem particularly common that people are contracting this disease through surface transmission of COVID-19. As a result, we should focus on where people are contracting this disease, and that is through the air, not through surfaces.”

Some schools (not in LA) are opening and undergoing deep cleaning. Is that also a waste of time? 

“It's a huge, huge waste of time. The way to keep kids safe in schools is twofold, maybe threefold. 

Number one, you have to reduce community spread. It's just not feasible to open up schools while there's a huge live outbreak happening in your community. 

Number two, you have to find a way to ventilate school spaces. Open up windows.Separate kids, make sure they're not sort of breathing and screaming right on top of each other.

And then third, find ways to keep them away from each other throughout the school day, so you don't have … dense packing in of students in these … unventilated indoor spaces. And halls is a huge challenge. 

… Bragging to parents that you spend $100,000 on soap to scrub the tables and the blackboards and the doorknobs, that's hygiene theater. That's a waste of space. You can scrub the doorknobs until the day is done. And you've done very, very little to reduce the spread of what is fundamentally an airborne disease.”

— Written by Amy Ta, produced by Rosalie Atkinson