Masks are here, effectively forever. Time to rethink little bits of furniture, retail,
So, this note: first, something on the maths and science of mask effectiveness. A rumination on life in Taiwan and other parts of Asia. But first, a market for masks?
- Masks – health imperative and fashion market
As the pandemic swept toward the USA, masks were a hot commodity. We were urged, at first, to NOT wear them. A peculiar argument, which only made short-term sense – to enable medical front line workers to get them. And made terrible, long-term nonsense, since it encouraged strange thinking and worse actions. I’m not going to ruminate on the actions or motives of people who insist on not wearing them.
But now the shortages are past, I note my local Target has them in nice varieties. Neighbors have them in all types: macho boys and somewhat renegade musicians have bandana-style cloths. Tidy accountants have tidy masks. They’re necessities and they’re personal statements. We dare not leave home without one, so we may as well express our personalities. I’ve at home:
- Now-banned ones; solid-color but a one-way valve that preferentially lets my breath escape. Ooops.
- A small set of medical-quality N95s. Acquired a while ago, as forest fires ravaged nearby Northern California. I use these for dangerous trips into hostile territory. Like going to the grocery.
- A pair of quirky ones: one that renders my face into a cartoon version of a teddy bear’s mouth. I wear those out when the neighbors’ kids are playing.
- Three that a neighbor made! (She made some for my wife and one, I kid you not, has sequins on it.). I wear these while walking the dog or taking out trash.
- Some nice, easy-to-wear, white-only, enriched paper masks made by a company for its factory workers. I wore them plus a face mask to go to BLM protests, of course.
And so, my little collection of masks starts to resemble my no-longer-used set of ties, whose colors and styles and prints in their way expressed a tiny element of personality: conformance or edginess; color or drab. Except: masks are really useful and mostly require handwashing and gentle air drying, and some need a little place for the PM2.5 activated charcoal filters.
The contractors working here have sturdy ones with the company logo. A neighbor has a set of Biden 2020 masks. Another, a white woman, has Black Lives Matter masks. Etsy reports it has nearly 6,000 Black Lives Matter masks. Yay!! I think I’ll get the raised fist one!
Okay, then. So there are, what, seven and a half billion people on earth. And they all need masks. Now, some are going to go crazy and have lots. Some will say: these for work, these for social, these for that. The world’s billion or so wealthiest individuals will have 10 or 20 each. And replace them every six months or more frequently. That, friends, is 30 billion masks a year, at $5 or $10 apiece. Just like that, a worldwide market of at least $300 billion a year.
Masks are a much bigger retail market than socks (now that folks work from home a lot more, who wears socks?). No wonder big fashion brands are heading toward this: we need to buy them; they need to sell something – and, frankly, we also need the quality control of someone to assert that the masks are reasonably effective. And the design aesthetics of someone better than me or, probably, you. https://www.forbes.com/sites/sboyd/2020/04/24/5-fashion-brands-pivoting-to-create-masks-for-the-public/#5f05b756648f
- Why we wear masks: the science of the effectiveness of wearing masks
COVID is an airborne, respiratory pathogen. The principal vector is from via disease-carrying droplets expelled from the respiratory system of the infected person, via the air, into the respiratory system of the unlucky recipient. Droplets expelled by coughing, sneezing, wheezing, singing, shouting, talking, breathing.
Masks should work, then, right?
Here’s Larry Brilliant, epidemiologist of some noted: “If 80% of people wore a mask 80% of the time, COVID would go away.” Is that really true?
Really. Yes. They’re easy and inexpensive, and the life you save may not be your own. So let’s note the science of how good they (and their wearers) have to be.
The science of how good masks need to be is well understood. The droplets start out (leaving the mouth or nose) in sizes from low tens of microns to low hundreds of microns. They shrink – due to evaporation – but then stay airborne, with smaller droplets staying in the air longer. So the first lesson is: since they’re bigger as they’re exhaled, it’s critical that the infected person has something to block droplets. But, as we all know: there’s a long period during which a person is infected and contagious – but doesn’t have symptoms. And decent cloth is really good at blocking droplets. Masks are pretty good at blocking inhaled droplets as well – but they don’t have to be that good there.
These pictures show the principle: more violent or more prolonged respiratory output is worse, and masks well at preventing transmission.
These ideas give mathematicians enough to get cracking on modelling. It’s hard work but the basic idea is to answer the question: what level of face mask adoption by the public, associated with what level of face mask efficacy, would be required to reduce the effective reproduction number (R) below 1? And the answer is … indeed, Brilliant is right. If nearly everyone wore reasonably effective masks nearly all the time … COVID goes away.
The graphs attached show modelling (Oxford University group, Stutt et al) that examines effectiveness at quashing transmission of COVID given lots of variables: the effectiveness of the mask – the graphs reading from left to right represent increasing effectiveness; the R(0) of COVID – the blue lines are the higher R(0) estimate; whether the masks are only worn after symptoms are determined (top rank) or all the time (bottom rank); and what percentage of people wear masks – each graph, from nobody to everyone. Each of the eight little graphs shows the effective R (written as R/e) in each case. The goal: R needs to get below 1.0.
OK, what to do?
First – compare the two rows. Wearing masks only after symptoms never does enough to spread contagion for R(0) = 4.0. Never.
Then look at the bottom row, the 3rd column – 75% mask effectiveness. Everyone, or nearly everyone, wearing reasonably effective masks, all the time ( = outside your household) kills the spread of COVID.
The message: Don’t wait for someone to have symptoms. Always wear masks. Limit your exposure to unknown places and people. Always wear masks.
- Masks and culture in Taiwan (and Japan, Hong Kong)
Crowded cities, packed trains, high humidity, people eating out all the time. Almost no COVID deaths.
Taiwan, particularly, I know because I lived there and have many friends there. When I lived there, it was a decade after the SARS epidemic of 2002 – 2003. But the reflex was there: masks everywhere. If someone thought they had a cold, perhaps felt a little run down or had a sore throat coming on: wear a mask. Employees at stores where they were in constant contact with the public – convenience stores, like 7-11, banks, train stations, toll takers on the highways: always wore masks.
And, Taiwan has a decades-old tradition of scooters as a means of inexpensive transit, and a nasty, long history of unconstrained dirty industries. Both meant that the air was sometimes filthy with soots and chemical fumes. You know what works well for these?
Scooters in Taipei: https://totobobo.com/blog/2019/02/totobobo-for-riding-a-scooter-in-taiwan/
And so it was, of course, that I developed a sore throat one particularly cold, damp winter. Off to 7-11. Masks for sale included nice masculine ones in sober colors and cute pink ones for young girls and Hello Kitty masks for dating-age young women. Of course, the would-be-tough young men would wear ones with death’s head skulls, but 7-11 doesn’t stock those.
Taiwan was and is where we all will be. Respiratory diseases are well quelled by wearing masks. They’re inexpensive and they can save lives. Done well, they express your personality. We’re going to have to wear them, either by mandate, or because we are humane enough to not want to be vectors of contagion. Cool. Let’s do it!