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COVID-19/Coronavirus thread


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On 11/12/2020 at 7:33 AM, hi8is said:

Look on the bright side, I can give you a haircut.

Look, this is developing. Americans can change their minds about things.My mistake is expressing changing moods on the message board as a way to stay sane.  Yes my mental health was being affected during the last lockdown and 3.5 months with no haircut and hippie-like hair status was affecting me mentally. Would a psychiatrist have helped me? Probably. Right now I'm very very concerned about everything COVID related. I worry when I hear there's no bed for my neighbors and relatives at the hospital if needed. I just hope numbers decrease somehow as we enter the brutal months of winter when viruses spike.

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2 hours ago, southsider2k5 said:

June 22nd the entire state of Indiana recorded 210 new cases. Today (my home county of about 100k people) LaPorte County collected 143 new cases, BY ITSELF.  The state of Indiana recorded 6591 cases.

Slackers. Texas topped one million total. Stop the count!

 

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When it was new in March/April, it was scary and numbers hard to grasp, but was fortunate it wasn't visible anywhere around me. Coworkers, friends, neighbors, schools, offices, all safe from it at first.

That's not the case right now, these are huge numbers but it also feels as huge as it seems. Neighbors coming down with it, family, friends, coworkers. 

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3 minutes ago, bmags said:

When it was new in March/April, it was scary and numbers hard to grasp, but was fortunate it wasn't visible anywhere around me. Coworkers, friends, neighbors, schools, offices, all safe from it at first.

That's not the case right now, these are huge numbers but it also feels as huge as it seems. Neighbors coming down with it, family, friends, coworkers. 

So true. In the past week I've been two degrees away from Covid patients with three different scenarios. Waiting to see if the person I was near comes down with it is a lot of stress.

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39 minutes ago, Texsox said:

So true. In the past week I've been two degrees away from Covid patients with three different scenarios. Waiting to see if the person I was near comes down with it is a lot of stress.

by the way I actually got a talk this week from an aerosol particle dispersion expert if you’d be interested in how much air is being exchanged from one person to another.

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1 hour ago, Texsox said:

Balta, details please. 

Ok.

So, the first answer is that before this, no one really did anything like air exchange calculations from person to person over time, so the models are rough and being adapted from other things, like atmospheric pollutant transport. Hence, geoscience. 

If you assume fairly quiet conditions and 2 people standing 3 feet apart outside then the amount of air exchanged between 2 people directly over an hour is about half a liter. 

For comparison, same 2 people in a moderate sized room for an hour exchange about 10x as much air directly. ~4 liters. Smaller room, more air exchange. More rapid breathing = more air exchange. Distance only matters if you’re about a foot or two apart where the dose rises rapidly, because otherwise the whole room becomes well mixed and homogenized.

Now for all the qualifiers. The more things you plug into the model the more complex it gets. Wind. Air conditioning. Filtration. Yada yada yada. Basically, we have models that can handle this, but you have to do room by room, condition by condition. Windows open. What happens if people stand up and disrupt air flow. Now that we’ve seen this as a trillion dollar worry, this sort of modeling can actually be done before you open a building for the first time. Where do you put airflow, how much air needs to move, how do you balance that against cost. A single big room could be modeled several dozen times for different conditions. That is the long term basis for government standards for building development that can reduce pathogen transmission.

Now, what is required for transmission? Well unfortunately they don’t know that, because the biologists don’t know yet either. They know there is a required dose, but they are thinking in terms of log units of virus particles and it’s hard to know right now within 3 log units. They know that virus particles are spat and breathed out of people in various sizes, but they don’t know what size particle is the most important for transmission or how much of each would do it.

But there are some things we do know. Most particles that are 100 micrometers (μm) in diameter (human hair is 3-50 μm) do settle out towards the ground within a couple feet. This is the size social distancing works for. But we know this virus can travel farther than that, meaning that large particles are likely capable of transmission, but social distancing beats it. Masks also dramatically stop particles at this size.

Particles that are less than 1 μm are effectively aerosolized. These basically never settle out of air. They will stay in air for hours, maybe days. Masks other than gas masks effectively do nothing against particles of this size. Ventilation, high grade filters, and staying far apart are the only defense against particles this size.

Inbetween we have a problem. 10 μm particles are notoriously difficult to work with. Air pollution of this size is hard to sample. You can’t do it with normal filters or sampling devices. Filters do catch them, masks will limit them, but a substantial fraction gets through both, and they can travel long distances and not settle out. If these particles are suspended in a closed room they can stay there for hours. Air pollution this size can cross the Atlantic.

If aerosols were the only thing that mattered, then masks would do nothing.  If large particles were all that mattered then distancing and masks would stop it perfectly. We know masks help but they aren’t perfect. We know distancing helps but it isn’t perfect. So all sizes are probably involved, and you need to worry about concentration of each.

Stay outside of 1m and you avoid the big particles, especially with masks as they settle out. Outdoors helps then because you dilute the dose over time, but it isn’t perfect, especially if you talk about an hour or several. Indoors, masks are strong over a few minutes and decline pretty quick over tens of minutes in small rooms (normal restaurant sizes) Ventilation helps but is an extremely complicated calculation depending on the details of every single bit of the room. If you are indoors for tens of minutes, masks help, but the longer you are in the room the more air you exchange directly and small particles that aren’t stopped by masks don’t settle out. 

The worries are: with more time indoors, exchange of air goes up logarithmically. In 1 hour you exchange 4 liters of air, in 2 hours it becomes dozens. The examples of businesses and bars and restaurants becoming infected, that’s how it happens. 2 hours and you’ve breathed in 20 liters of air from a person 20 feet from you. Although no one has measured this, it also implies a very strong delayed effect - if someone infected was in the room an hour before you get there, you come in, they’re gone, but the room is still contagious if it hasn’t been strongly filtered. 

Outdoors, ten to tens of minutes is a risk. Lack of masks accelerate this, but not beyond ten minutes or so. If you are closer than 1 meter, exchange rises dramatically and transmission in minutes could be possible. Over an hour, exchange over 2 meters may be possible, but depends on conditions like masks, wind, and turbulence.

It will be possible to dramatically improve these numbers with computer models designed for this and better numbers foe virus dose, but neither of those will be available for years.

Forgive any font changes as my phone had to copy and paste μm. Unit changes happened during her talk. 

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https://www.wsws.org/en/articles/2020/11/13/plot-n13.html

According to a legal brief recently filed by Michigan Attorney General Dana Nessel, the fourteen militiamen who were arrested in October for plotting to kidnap and kill Michigan Governor Gretchen Whitmer also planned to storm the capitol, capture hostages, live stream a horrific series of executions, and target the entire elected state leadership and members of the state legislature.

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I have a few questions,  but I jumped out,  the affect of wind in the outdoor settings.  If I'm downwind of someone doesn't the distance calculations change?  It seems in theory we're could help protect people if we tried to have a strong crosswind. 

The ideas of buildings being designed to mitigate disease transmission is fascinating.  What would be some things we could observe? 

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So much from the right has been against social distancing. They come with this stupid crap that the radical left is not only keeping them from going to church, but this is a plot to destroy religion in America.

In my wife's church, most of the congregation is over 50. Most have conditions that compromise their immune systems which isn't surprising. The decision was made months ago to hold services online. The congregation misses going the church, but they realize they have to put that off for a time.

My wife and a couple others are visiting a member at a nursing home. Of course, they will be seeing the member through a window. The member is not expected to live past next week.

Do these Trump-lovers think the members of this church like all of this stuff? Do they think that saying good-bye to a person through a window is great? There just isn't realistic fucking alternative to all this crap.

There is so much insanity going around this country. We'd be better off if the Trump-lovers would wake up and realize their savior has lead them down the garden path.

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5 hours ago, Texsox said:

I have a few questions,  but I jumped out,  the affect of wind in the outdoor settings.  If I'm downwind of someone doesn't the distance calculations change?  It seems in theory we're could help protect people if we tried to have a strong crosswind. 

The ideas of buildings being designed to mitigate disease transmission is fascinating.  What would be some things we could observe? 

The answer with wind is probably it has an effect but it’s within the error bars of a factor of 10. If you are within 1 meter, you’re exchanging a lot of air so wind might not make a big difference if you’re there for tens of minutes. If you are perfectly seated downwind and 2 meters away maybe wind increases air exchange, but wind is turbulent, it is going to mix the air you breathe out with fresh air, and the wind direction isn’t typically perfectly constant. So maybe you go from 0.4 to 0.6 liters in an hour exchanged, a 50% increase. Could that be enough to be the difference between getting sick and not? Yes, but now that depends on the amount of virus a person is giving off and what is actually required to make a person sick, which we don’t know to within factors of 100, so that factor of 2 is hard to plan for.

You might not notice anything in a building built for this. Right now your school probably has rooms that do better and worse than each other based on vent positions, desk and person positions, airflow, etc. You might have to plan to not move desks or something like that to make sure airflow isn’t disrupted if you were in a room built to minimize transmission.

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I feel awful for the restaurants, and hope something can be done to save them (Mitch McConnell). The one thing I don’t understand walking around my neighborhood with no indoor dining, is why is dining indoors bad, but dining in an enclosed tent on the sidewalk is just fine? Seems to me to be the same problem only colder. In fact Tavern on Rush has constructed an enclosed glass structure covering the sidewalk. Why aren’t these considered inside? I know one thing, there isn’t a chance in hell I will be in one unless I just have to get Covid.

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12 hours ago, Dick Allen said:

I feel awful for the restaurants, and hope something can be done to save them (Mitch McConnell). The one thing I don’t understand walking around my neighborhood with no indoor dining, is why is dining indoors bad, but dining in an enclosed tent on the sidewalk is just fine? Seems to me to be the same problem only colder. In fact Tavern on Rush has constructed an enclosed glass structure covering the sidewalk. Why aren’t these considered inside? I know one thing, there isn’t a chance in hell I will be in one unless I just have to get Covid.

It’s not. An open tent is better than indoors, a closed tent is basically the same or worse. It’s another symptom of us not taking this seriously.

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9 hours ago, greg775 said:

Just got back from big grocery store. No toilet paper or paper towels. Gone.

We are turning the corner. This will just go away. If your governor puts restrictions in place, listen to Dr. Atlas and rise up. No need to follow the science. It's gotten us to this point. 

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