Basic Science
Sadly, Not Always Learned…
Some misinformed young woman tried to post to this blog tonight about how cloth masks do not stop the actual virus much at all and studies have proven that because the actual virus is too small.
She is right. If the virus just floated all by itself in the air, a cloth mask would not stop most of them. Of course, one single virus particle does not carry the virus load needed to infect anyone in almost all cases, but that is beside the point.
But thankfully, the transmission of the virus comes from someone who is infected talking or singing or shouting in a closed space without a mask. When a person makes a noise like that, or sneezes in the extreme cases, or coughs, a ton of spittle is sent out in to the air. Nature of the human animal.
The larger droplets with the most virus load fall quickly to the ground or a surface. (How long it stays viable on a surface depends on the surface and on a person getting a large part of that virus load on fingers and then touching their nose, eyes, and sometimes mouth.)
The smaller droplets can fly for a while, sometimes across a room if conditions are right. These small particles have a lot of the virus in them, but usually all alone one tiny spittle does not have a virus load large enough to infect a person in most cases.
That’s why the distance of six feet is so important. Gets a person out of the range of the larger, viral loaded spittle and most of the medium size stuff we all spit out when talking.
But when a person spends time breathing in a lot of these small spittle particles with virus in them, then an infection can occur.
Why the scientists say time is a factor and enclosed spaces is a factor. Outdoors with good air movement is the best.
Cloth and other types of masks, stop the small spittle particles from building up and stop a large, large percentage of them. But even if you are wearing a mask, if you are in a bunch of infected people in a small space for a prolonged amount of time, you will most likely get it.
But where a mask is critical is on the infected person.
Then most of the small and all larger particles are stopped almost completely in the mask the infected person is wearing. And if the person close by is also wearing a mask, the rate of transmission is so low as to be not counted. And if the two people are six feet away from each other, or are only passing, or in good air movement, the risk drops just about to zero.
Problem with this virus is that a large number of the people infected don’t have symptoms and thus are just walking virus spreaders. Especially younger people who think they are immune and don’t need to wear masks.
Masks aren’t everything, but they allow us to live our lives.
This poor young woman really, really wanted to school me how cloth coverings don’t stop most virus particles because a virus is too small. And she was taking me to task about promoting people wearing masks. (Not kidding.)
She is right, as I said, that a cloth mask can’t stop a single virus particle, and thank heavens the virus can’t float by itself or infect a person from a single virus in most cases. It takes a virus loa. So because the virus is spread on droplets we all spit out when we talk, we can protect ourselves and everyone around us with something as simple as wearing a mask to stop most of the droplets before we spit them into the air and into other people’s lungs.
And by washing our hands all the time, using hand sanitizer all the time, and not touching our faces, that helps on the surface stuff as well.
This really isn’t rocket science, folks, and the real information is out there.
Sorry this bored those of you smart enough to actually already study what is impacting all of us at the moment.
I guess like copyright for writers, I am stunned at how purposely ill-informed so many people want to remain about this virus. Especially when all this information is right on your computer.
And by the way, you have to wear the mask to protect others over both your nose and mouth. Can’t be under your nose. Just watch a test. They put a stick up your nose to see if you have the virus. Duh…
16 Comments
Chong Go
Here in Korea, we’ve had so many cases where someone turned out to be infected, but when the local health department did contact tracing on them – interviewing them, looking at their phone GPS and credit card usage – they found no infected people. The common tread? The people had been wearing a mask, even though they didn’t have any symptoms. They just did it because they didn’t want to accidentally give this virus to anyone else.
Where does this conspiracy stuff come from? I was grumbling about this to a Korean friend (who is very much a nerd), and her answer: Pod people! Lol.
David Ai
This is the most cogent and concise description of why mask wearing is important. We’ve been wearing masks since January in Hong Kong – and the results speak for themselves – negligible local transmissions. Mostly imported… and a very few people infected due to faulty waste systems in their old apartment buildings. Flush toilets with those lids down!
Mass transit does not increase infections
High density living does not increase infections
Not following the science does increase infections. Listen to Dean – he’s totally onto it.
dwsmith
People should always do that with toilets anyway. (grin) Got a hunch this virus is going to eventually make for a healthier country, with all the hand-washing. Chapped hands, but cleaner. (grin)
Milla
I’m from Sweden and the recommendations here are to NOT wear a mask unless you’re working with suspected covid-19 patients at care homes or at hospitals. The reasons for this, they say, is that with a mask you tend to touch your face more often and hence run a larger risk of tranmitting the virus onto your face.
This makes me so sad and upset, I’m absolutely positive that a lot of lives could have been saved if the recommendations had been different. I ’ve chosen to wear a face mask even though the majority do not. And in Stockholm where I live it seems as most just want to get on with life and pretend that the virus never existed. 🙁
Philip
I wear a cloth neck gaiter because frankly that’s what was easiest to find when this thing first started. I caught a lot of heat from people telling me any non N95 mask was “useless.” Bottom line is I’m confident my gaiter protects me and my neighbors when I’m out grocery shopping (which is really the only time I go out). I’m glad I work for a company that how now permanently implemented work from home, too. We’re in a new world. Sadly, everyone in this new world seems to think they’re experts.
Martin
Thanks, Dean. It is also helpful to avoid the desinformation on Facebook 😉
Jason M
I read that a strong sneeze can send the viruses 25 feet.
Mike Southern
When this whole virus thing started, Discovery Channel re-aired an old Mythbusters episode (recorded 10 years or so ago) where they tested the different ways viruses are transmitted. (Granted, this was normal viruses and not airborne viruses, but the info is still useful when talking about contact.)
If I remember correctly, their study of how far a sneeze traveled topped out around 33 feet. Of course, the bulk of the droplets fell much closer to the sneezer (hence the standard advice to sneeze into your shirt sleeve or a tissue) but the farthest droplets got out there quite a ways.
The irony of it all is that, if you simply added the mask to stop the droplets as they came out of your mouth or nose, their findings matched the advice being given by the medical advisors on how to slow down the spread of COVID-19. Most interesting was the fact that, even without using sanitizer and such, they showed how easy it is to stop a virus almost totally just by using a little common sense and some courtesy.
dwsmith
Yup, that was a great episode. And thank heavens this Covid virus can’t float and have enough viral load to infect by itself. It must be carried in the spittle to have enough to infect.
Thanks, Mike. Good reminder.
Teri Babcock
Dean, I was not bored but heartened at the great job you did explaining transmission risks so clearly and correctly, and to see the comments from people who get it.
C.E. Petit
(n.b. somewhat out-of-date degree in chemistry one course short of a biology minor behind this)
Infection — whether bacterial or viral — is all about two bits of math:
* the concentration of vectors at the target, and
* the concentration of defenses at the target
A mask of any kind — N95, cloth, disposable, makeshift bandana — at the source vastly cuts down the concentration of vectors that can reach the target. And bluntly, short of certain extreme environments in which neither the source nor the target organism can survive either, there is nothing that is truly 100% effective in killing vectors, whether bacterial or viral. (We’ll neglect the whole “build up resistance over generations” thing for the moment; it’s more complicated than can be explained accurately on a blog.)
And, in turn, that gives the defenses at the target a greater opportunity to reduce the vector load below the level necessary to cause an infection in the target. Those defenses can be physical barriers (masks, face shields, even everyday glasses!), chemical (washing one’s own hands to degrade and slough off vectors), and biological (ensuring that one’s own respiratory health is as good as possible to allow the alveoli to isolate vector materials because their mucoid systems are not overloaded).
The key point is that unlike, say, polonium, a single or very small number of virii (or bacteria) cannot cause very much damage that the body cannot tolerate and/or repair. Wearing a mask keeps the number of transmitted vectors much lower, possibly below the infection threshold all by itself.
dwsmith
Thank you, C.E.! Spot on and really appreciate it.
dwsmith
Clare
I don’t really see why her age or gender is relevant?
dwsmith
That’s just the fiction writer in me. If it had been an older guy, I would have described him that way, or an older woman, I would have described it that way. That is my fiction habits coming forward. However, the younger part is sort of relevant at this moment in time. The woman or man part is not.
Sheila
What always makes me wonder is the advice my mother’s doctor’s office gave people back in early March, which was that masks were of no use to either prevent spreading or infection. They’d removed the mask/tissue/hand sanitizer stations from their office. How many people were at risk then, because of this advice? Now, of course, they are limiting occupation, have the stations back, require masks, and have people who go around every so often and wipe everything down.
Nothing is 100% sure to prevent someone from spreading or catching the virus, outside of never being in contact with anyone or anything, from months back and onward to the future. Not likely that’s going to happen. Best any of us can do is be careful, follow the guidelines we know at this time, and hope.