Posted on 04/01/2020 1:15:03 AM PDT by wastoute
How may virus particles (visions) does it take to start an infection?
I don’t think anyone knows for sure but over the decades, at times like this, one ponders these things. My thoughts go along these lines, some things are known, much not. A lot of information is “proprietary”.
If one viral particle (virion) is inhaled and lands on a nasal epithelium cell, on a specific receptor, it can...
How may virus particles (visions) does it take to start an infection?
I don’t think anyone knows for sure but over the decades, at times like this, one ponders these things. My thoughts go along these lines, some things are known, much not. A lot of information is “proprietary”.
If one viral particle (virion) is inhaled and lands on a nasal epithelium cell, on a specific receptor, it can then “do what it does” and infect the cells by transmitting it’s genetic material. That cell replicates 800 or 1,000 or whatever new virions, the cell dies from it and releases all those particles to start already x800 or so on surrounding cells. But is that “lone virion” always successful. You can imagine there is a scenario in which the virus binds to a cell that is already about to die and in infecting the cell both “perish”, the cell dessicates the virus is wrapped in a shroud of dead cell, and both are sloughed off and blown out the nose.
So, theoretically, there is at least some risk the virion won’t be successful. Now we can begin to talk about probabilities and thanks to Statistics we have an excellent tool to do so. So while we may not have the technology to “see” one virion do what it does, like Psycholgy needs not understand the brain in detail, it is the study of Behavior, we don’t need to put our virion on a couch and ask questions about it’s childhood. We look for the behavior of the disease and theorize , “if that were happening, this is what we would observe”.
So how many virions does it take? AFAIK, no one knows this for any virus. I don’t think it’s “knowable”. But it sort of stands to reason that if one got an “inoculuum” heavily loaded in multiple droplets that each, due to the relatively large size of the droplet compared to an aerosol, heavily laden with many, many viral particles a patient would have a serious “jump start” over the patient exposed to a “lonely pioneer”. The patient could get sicker, faster. Potentially it could make a real difference in the clinical course of the disease.
Let’s assume two cases. One patient gets exposed by a massive droplet exposure where many droplets are inhaled and another where one little virus made it into the nose placed there by a contaminated finger from a doorknob. With just a little imagination you could easily see how the two exposures are so different the clinical course of the disease is likely different. The first may get very ill very quickly, the other have a longer prodrome, the immune system gets a chance to get off it’s back foot, and the patient has “mild” or no symptoms.
Once infected the new virions are released in every cough, sneeze, wiping of mucus on surfaces, etc. we know flu and cold are droplet spread. I believe the “smart people” are starting to realize (the one thing we learned in Med School about this previously considered to be “of no clinical importance” family of Coronaviruses) was they escaped detection for a long time because the are so small and compact. See if you can find an image to compare in scale to”The Dane Particle” for instance. Why that was so gets technical but there it is. We know these virions are among the smallest virions out there.
So it stands to reason that there could be some people who were “lightly infected” who because they are young and healthy are able to produce “Clouds of aerosol” loaded with a lesser # of virions. Droplets are subject to temperature, humidity, sunlight, and gravity. Due to their small size aerosols “float” in air and linger for a very long time, immune to gravity.
I do believe the “smart people” (I say smart people because there is some disdain for clinicians among the people who strive for Revealed Truth in their Ivory Towers and it is returned for good reason, as clinicians we have to deal with the wreckage when they screw up, anyway) are beginning to realize this as through contact tracing they discover “super spreaders”.
So, it is possible that clinical progression of the illness could be a function of inoculuum, could produce a very mild illness with an astronomical Ro but no fatalities, but one superspreader can “find” those few people with diabetes or some other disease that makes it harder for their immune system to get off it’s “back foot” and those few get a very serious form of the disease even though it is aerosol. Now those patients become huge droplet spreaders.
So you can see how just based on largely theoretical arguments we can begin to see just how many different “flavors” of patients there are out there.
So what’s the topic today? Masks? Conjoined twins?
your question is answered reasonably here, sorry this is a pdf link not html
https://wwwnc.cdc.gov/eid/article/11/12/pdfs/04-0949.pdf
I doubt very strongly is either of these is true.
I vaguely remember seeing that back then. The “sewer pipe” specifically. This article does look at this stuff. There are people who study this stuff all the time but what they know is “proprietary”. National Defense. If you know you may face aerosolized bioweapons you might want to thoroughly know as much as possible. The DOD came to this conclusion in the 70s, SARIN gas and most nerve agents,as well as Bot Tox and Anthrax are aerosols.
Believe it or not the wall of text above was in response to “your thoughts”. It has happened.
We were told, “It is unethical to make decisions for that patient.” I spent a career educating people to help them make their own decisions. That was my job.
It’s “viral load” theory, idea that how much virus you get can determine
* how likely you are to get it
* how severe a case you have when you get it.
“viral load” is the key term to search for more
The word for the day is psychotropics.
So, in order to understand the “mask controversy” you need to be aware of the concepts. The use of masks in Medicine was part of the introduction of “Science” in Medicine 100 years ago. Surgeons wore mask in surgery for understandable reasons which were “new” at the time. It was discovered in the 40s or thereabouts that if you put a surgical mask on a TB patient it stopped or severely reduced the transmission of TB. I think this was the first use of masks for patients.
As growing awareness of asbestos occurred in the 70s people began there was a great need in Industry to protect workers from “Respirable Dust-5 microns or less), the reason we no longer make building from stone so much is Silicosis.
It was realized right away the “masks” that protect people from TB didn’t have to do what masks that were intended to protect the wearer. To protect the wearer the mask must be sealed so no air can be inhaled around it.
So why the controversy? When I was in training in the 80s Bone Marrow Transplants were a new thing. Destroy a Pearson’s immune system concurrently with EVERY SINGLE CANCER CELL could potentially save a cancer patient’s life and their immune system could be “recreated” by transplant afterwards. It worked for some cancers. The large urban hospitals where doctors are trained began putting up “Laminar Flow Rooms” for these patients to protect them during the phase when they had no immune system whatsoever. Even Pediatric Hospitals, big names you see everyday, had only one or two.
The Infectious Disease people realized the “Isolation” of old used largely for TB patients was no longer enough for “Isolating” in the hospital those patients who had VERY communicable diseases, such as measles, so they started engineering rooms that weren’t quite as aggressive as “Laminar FLow” but simple “negative pressure” was enough.
Here is the source of some of the controversy. In Medicine, the place where we have used “sealed masks” or “respirators” is in these negative pressure Isolation Rooms. AFAIK it is the only place in the hospital where these type of masks were worn. Which is why I posted and you are hearing, the place where these masks “do their job” is in these rooms and by staff who are trained in how to avoid their failures (touching the outside of the mask on exit, etc,)
what controversy are you talking about?
LOL. It was rhetorical. But I think to understand the “mask controversy” there really are some concepts you have to understand first.
Should the public wear masks?
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