On Masks

Why do they work? What could make them better?

Lots of folks don’t seem to understand masks. I’ve seen some folks say that the virus is too small to be stopped. But most pollutants, dust, viruses, do not exist in air by themselves in a simple and lonesome form. Even when floating in air, things want to stick to other things. Regular stitched masks without special filters aren’t perfect, but they can block a lot of small conglomerations. Moreover, the more doublings of cloth can make that even better. The tradeoff of doublings up is the efficiency of breathing—the thicker the mask, the harder it is to pull air through.

In a different area, cholera in water, see NIH: Fogarty International Center: February 2015: “Sari cloth can filter cholera from water, research shows”. In that study, villagers in Bangladesh used simple cloths, folded twice (for four layers), to filter water as they collected it. It filtered 99% of cholera bacteria from the water in lab tests, and while the real-world use probably wasn’t as effective, it still cut cases and the cases that developed were milder.

Simple interventions can be effective. Masks do help, even if they aren’t N95 masks. Even if people make some mistakes in wearing them part of the time. They still help.

Separating the mouth covering and the nose covering would improve masks.

The nose is a challenge due to the variety of shapes, but more importantly it could be continuously covered even when the mouth needs to be uncovered. It is very easy for the public to cover the mouth and not realize their nose is uncovered, mainly because of the natural tendency to forget our noses. Noses are passive. Mouths are active. We do all sorts of things with our mouths, like eat, drink, brush teeth, talk, sing, whistle, play musical instruments, chew gum, and so on. Most of what we do with our nose is breathe.

I’ve often seen, sometimes in person, but often in photographs, people without their noses covered. I admit, I made the mistake on one occasion, myself. It’s an easy mistake, but we breathe through our noses, so it’s important to cover.

By covering the nose itself, or through some other method of protecting the entrances to the nasal airway separately, most of the inhaling could be protected and a common mistake could be countered. It would also make the masks more comfortable to wear, as a combined design is harder to make than two separate designs.

One of the most important things about that Sari cloth study is the fact that cases were milder. Masks do not block all cases, but likely do lead to milder ones. That may help reduce the transmission rate, but even if it doesn’t, it surely saves lives.