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-   -   How Is Covid-19 Impacting Life in Your City? (https://skyscraperpage.com/forum/showthread.php?t=242036)

Pedestrian Jul 8, 2020 6:43 PM

Quote:

Originally Posted by suburbanite (Post 8974403)
A friend works for Ernst & Young where their entire 10 floor Toronto office is all "hoteling" desks where you have to book a seat every day if you're going to the office. Even partners' offices are opened up to everyone else if they are out of office. How they plan to logistically sterilize such an operation when they return to work is beyond me.

Some companies have put out thought pieces on how this may reverse the decades long trend of moving towards open concept flexible workplaces. I think people have short memories and are still going to flinch at spending hundreds of thousands to revert back to a cubicle & corner office setup.

The notion that coronavirus is spread from surface contacts was overhyped in the early days of the pandemic. In fact, most spread is probably airborne which means the risk on going to the office is from the commute if any part is on public transit, using an office building elevator, bathroom, break room or other facility where you may be with others in a closed space, or generally existing with other people indoors without strict distancing and mask-wearing (and an HVAC system that brings in large quantities of outdoor air and/or filters indoor air to a very high standard). Cleaning office surfaces at night or when unoccupied is almost irrelevant, no matter how thorough. They could be contaminated 5 minutes after the office opens in the morning if a co-worker is an asymptomatic carrier and more importantly, so could the air circulating in the office.

lrt's friend Jul 8, 2020 8:17 PM

Quote:

Originally Posted by Pedestrian (Post 8974791)
The notion that coronavirus is spread from surface contacts was overhyped in the early days of the pandemic. In fact, most spread is probably airborne which means the risk on going to the office is from the commute if any part is on public transit, using an office building elevator, bathroom, break room or other facility where you may be with others in a closed space, or generally existing with other people indoors without strict distancing and mask-wearing (and an HVAC system that brings in large quantities of outdoor air and/or filters indoor air to a very high standard). Cleaning office surfaces at night or when unoccupied is almost irrelevant, no matter how thorough. They could be contaminated 5 minutes after the office opens in the morning if a co-worker is an asymptomatic carrier and more importantly, so could the air circulating in the office.

Can you provide the back up for these claims? It is very common belief that all viruses are frequently spread by touching contaminated surfaces. I am not disagreeing that viruses are also spread by inhaling droplets but it is very presumptuous to assume that touching contaminated surfaces is not a major way of spreading virus.

eschaton Jul 8, 2020 8:26 PM

Quote:

Originally Posted by lrt's friend (Post 8974926)
Can you provide the back up for these claims? It is very common belief that all viruses are frequently spread by touching contaminated surfaces. I am not disagreeing that viruses are also spread by inhaling droplets but it is very presumptuous to assume that touching contaminated surfaces is not a major way of spreading virus.

Health experts have repeatedly said that just because a virus can be detected on a given surface does not mean that the surface is actually infectious. There could be simply broken partial viruses present on the surface, or the number of live viruses could be to small to matter.

Also, since there is a belief now that viral load matters when it comes to how sick you get with COVID-19, some are suggesting you shouldn't be too careful about surfaces because if you have to get infected, it's better to get infected from a surface - since it makes it much more likely you'll get an asymptomatic or mild case.

Pedestrian Jul 8, 2020 9:08 PM

Quote:

Originally Posted by lrt's friend (Post 8974926)
Can you provide the back up for these claims? It is very common belief that all viruses are frequently spread by touching contaminated surfaces. I am not disagreeing that viruses are also spread by inhaling droplets but it is very presumptuous to assume that touching contaminated surfaces is not a major way of spreading virus.

That may be a common belief but it's wrong and probably based largely on flu virus which IS spread commonly by what's called "fomites" (that is, surfaces).

Quote:

The primary and most important mode of transmission for COVID-19 is through close contact from person-to-person. Based on data from lab studies on COVID-19 and what we know about similar respiratory diseases, it may be possible that a person can get COVID-19 by touching a surface or object that has the virus on it and then touching their own mouth, nose, or possibly their eyes, but this isn’t thought to be the main way the virus spreads.
https://www.cdc.gov/media/releases/2...nsmission.html

Let me repeat that: ". . . it MAY BE POSSIBLE that a person can get COVID-19 by touching a surface or object that has virus on it . . . but THIS ISN'T THOUGHT TO BE THE MAIN WAY THE VIRUS SPREADS . . . ."

Does that sound to you like they are saying touching contaminated surfaces is a MAJOR WAY the virus spreads? It doesn't to me--sounds like they are saying that's at most a MINOR phenomenon.

The point here is that rather than obsessing about surface contacts with expensive cleaning (and that developing world spraying of disinfectants on pavement), you'd be much better advised to obsess about what you are breathing. The bad news here is that we are finding out that the virus that people expel can linger in the air for hours so "social distancing" is also a fraud. If you stand 6 ft from someone and then everybody circulates so that you are where another person was a half hour ago, you can be breathing their exhaled virus.

Quote:

Aerosol and Surface Stability of SARS-CoV-2 as Compared with SARS-CoV-1

Letters
TO THE EDITOR:
A novel human coronavirus that is now named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (formerly called HCoV-19) emerged in Wuhan, China, in late 2019 and is now causing a pandemic.1 We analyzed the aerosol and surface stability of SARS-CoV-2 and compared it with SARS-CoV-1, the most closely related human coronavirus . . . .

We found that the stability of SARS-CoV-2 was similar to that of SARS-CoV-1 under the experimental circumstances tested. This indicates that differences in the epidemiologic characteristics of these viruses probably arise from other factors, including high viral loads in the upper respiratory tract and the potential for persons infected with SARS-CoV-2 to shed and transmit the virus while asymptomatic. Our results indicate that aerosol and fomite transmission of SARS-CoV-2 is plausible, since the virus can remain viable and infectious in aerosols for hours and on surfaces up to days (depending on the inoculum shed). These findings echo those with SARS-CoV-1, in which these forms of transmission were associated with nosocomial spread and super-spreading events,5 and they provide information for pandemic mitigation efforts.
https://www.nejm.org/doi/full/10.1056/NEJMc2004973

In other words, this bit of research does confirm the idea that virus may be present on surfaces though it doesn't address the question of how often or to what degree that virus is transferred in infectious quantities to the human respiratory tract. But what it also says is that human exhalations potentially containing viruses don't immediately settle out onto surfaces but linger in air for hours and so as you pass through a room or subway car you are passing through clouds of what people--especially any unmasked people--exhaled even hours ago.

lrt's friend Jul 8, 2020 11:21 PM

Quote:

Originally Posted by Pedestrian (Post 8974992)
That may be a common belief but it's wrong and probably based largely on flu virus which IS spread commonly by what's called "fomites" (that is, surfaces).


https://www.cdc.gov/media/releases/2...nsmission.html

Let me repeat that: ". . . it MAY BE POSSIBLE that a person can get COVID-19 by touching a surface or object that has virus on it . . . but THIS ISN'T THOUGHT TO BE THE MAIN WAY THE VIRUS SPREADS . . . ."

Does that sound to you like they are saying touching contaminated surfaces is a MAJOR WAY the virus spreads? It doesn't to me--sounds like they are saying that's at most a MINOR phenomenon.

The point here is that rather than obsessing about surface contacts with expensive cleaning (and that developing world spraying of disinfectants on pavement), you'd be much better advised to obsess about what you are breathing. The bad news here is that we are finding out that the virus that people expel can linger in the air for hours so "social distancing" is also a fraud. If you stand 6 ft from someone and then everybody circulates so that you are where another person was a half hour ago, you can be breathing their exhaled virus.


https://www.nejm.org/doi/full/10.1056/NEJMc2004973

In other words, this bit of research does confirm the idea that virus may be present on surfaces though it doesn't address the question of how often or to what degree that virus is transferred in infectious quantities to the human respiratory tract. But what it also says is that human exhalations potentially containing viruses don't immediately settle out onto surfaces but linger in air for hours and so as you pass through a room or subway car you are passing through clouds of what people--especially any unmasked people--exhaled even hours ago.

If this is the case, then why was washing hands and cleaning surfaces the first method recommended by health officials to protect ourselves from COVID, and there has been a tremendous delay in implementing mask wearing.

I do not believe that installing special air filters provides tremendous protection if somebody is coughing in close proximity. The cost of implementing such measures is another question.

iheartthed Jul 9, 2020 12:05 AM

Quote:

Originally Posted by lrt's friend (Post 8975167)
If this is the case, then why was washing hands and cleaning surfaces the first method recommended by health officials to protect ourselves from COVID, and there has been a tremendous delay in implementing mask wearing.

In the beginning, hand washing and cleaning surfaces was identified as a possible significant factor of transmission, but it was just a theory. There are some very interesting stories in the media about all the heavy criticism that the WHO is getting for being so slow to update their guidance for the how the virus is likely spread. And also for releasing extremely confusing official statements about how the virus is transmitted that directly contradict findings that health agencies have submitted to them. WHO guidance is one the reasons some orgs and countries are still relying on temperature checks, when its pretty well known now that people can be infectious with no symptoms at all.

Quote:

Originally Posted by lrt's friend (Post 8975167)
I do not believe that installing special air filters provides tremendous protection if somebody is coughing in close proximity. The cost of implementing such measures is another question.

A lot of health agencies believe that the virus is airborne, and can float in the air for several minutes after being shed by an infected person. That is why there is so much focus on filters.


https://www.nytimes.com/2020/07/04/h...-airborne.html

https://www.nytimes.com/2020/06/09/h...anization.html

Pedestrian Jul 9, 2020 2:58 AM

Quote:

Originally Posted by lrt's friend (Post 8975167)
If this is the case, then why was washing hands and cleaning surfaces the first method recommended by health officials to protect ourselves from COVID, and there has been a tremendous delay in implementing mask wearing.

I do not believe that installing special air filters provides tremendous protection if somebody is coughing in close proximity. The cost of implementing such measures is another question.

Because we are actually learning things as we go.

Also, everybody from Fauci on down has now pretty much admitted that we were lied to about masks because they didn't want people buying up the available supply--they wanted it available for medical personnel and "first responders" (proving how important they are).

I agree with you about air filters UNLESS the HVAC equipment is generally powerful enough to change the total volume of air in a space every few minutes and pass all that air through the filters. This argument becomes practical when you are talking about airplanes. The airlines would have us believe that the filters in their systems are effective to filter out virus-containing droplets and they turn the air over sufficiently rapidly to be highly effective. I'm yet to be convinced but I haven't researched the issue. I don't plan to be flying regardless.

Pedestrian Jul 9, 2020 3:03 AM

Quote:

Originally Posted by iheartthed (Post 8975225)
WHO guidance is one the reasons some orgs and countries are still relying on temperature checks, when its pretty well known now that people can be infectious with no symptoms at all.

Agreed. Temperature checks are mostly a waste of effort.

If we had the supply available, what we should all be doing is wearing N95 masks that we've tried to properly fit whenever we are indoors. If we did that, I think we could stamp this virus out.

But we don't have enough such masks and not enough people would wear them or pay attention to propper fit.

Incidentally, the most effective N95 for this purpose are the valveless ones because they prevent exhaling virus particles as well as inhaling them but you can accomplish pretty much the same thing by wearing even a thin cloth covering over an N95 with a valve and such an arrangement is probably more comfortable because it causes less CO2 buildup (which gives some people headaches and others claim they feel like they are smothering).

mhays Jul 9, 2020 4:23 AM

They're not a waste at all. They catch some number of cases, and that's extremely important.

In fact, a series of partial measures is the whole point of everything we're doing.

This stuff is all about odds. Infection rates are about multiplication...for example the infection rate, the number of interactions total, the care taken with each interaction, etc., all multiplied together. Any reduction in infected people walking around will tend to make the equation better, with fewer infections and deaths.

SIGSEGV Jul 9, 2020 4:25 AM

Quote:

Originally Posted by mhays (Post 8975430)
They're not a waste at all. They catch some number of cases, and that's extremely important.

In fact, a series of partial measures is the whole point of everything we're doing.

This stuff is all about odds. Infection rates are about multiplication...for example the infection rate, the number of interactions total, the care taken with each interaction, etc., all multiplied together. Any reduction in infected people walking around will tend to make the equation better, with fewer infections and deaths.

Yes, a 10% reduction in infections can easily be the difference between R > 1 and R < 1. 10 10% reductions is basically enough to take R from its base rate of ~3 to ~1.

CaliNative Jul 9, 2020 5:52 AM

Asymtomatic Spreaders & Testing
 
Should all food service workers and other workers who might be asymtomatic spreaders of covid be tested? "Typhoid Mary" was an asymtomatic spreader of "typhoid fever" (an intestinal pathenogenic salmonella bacterium spread by fecal contamination) who was placed in involuntary quarantine around 1910 when she kept getting food service jobs and making people sick. Is asymtomatic spread exaggerated? You certainly don't want these spreaders working in tight quarters, in nursing homes, restaurants etc. Some countries test all workers in these types of industries. The young often have no symptoms but might be spreaders.

Pedestrian Jul 9, 2020 5:53 AM

Quote:

Originally Posted by SIGSEGV (Post 8975433)
Yes, a 10% reduction in infections can easily be the difference between R > 1 and R < 1. 10 10% reductions is basically enough to take R from its base rate of ~3 to ~1.

Can you point to any legitimate studies that show public temperature checks being in any way effective? My problem with them is mostly that COVID notoriously causes petty high fevers—people feel pretty sick if they feel sick at all. It’s not a thing where somebody would be walking around, going to work etc not realizing they have a fever. So I suspect the number of people with COVID picked up by public temperature checks is vanishingly small. But I’ve seen no scientifically valid studies on the subject.

And a 10% reduction (which I bet is way in excess of what temperature checks accomplish) takes R0 from 3 to 1? Seriously?

dave8721 Jul 9, 2020 5:55 AM

Quote:

Originally Posted by Crawford (Post 8974380)
I don't understand how it's even worth it to open places like Disneyworld right now. Who wants to be outdoors all day in the summer Florida sun, masked?

Then half the attractions are closed and all the special events (fireworks, parades, etc.) are cancelled. And the Disney parks are obvious global attractions, and practically no one can even enter the U.S. for leisure purposes. So what's the point? A typical family is gonna drop 5k to play Russian Roulette and visit Pandemic Mickey?

I have no plans on going anytime soon (still have to do the kid drop off with wife's 70+ year old parents sometimes) but the only draw would be the fact that it is the one time when everyone wants to stay away and you would actually be able to enjoy it without the crushing crowds for once. Basically just go ride to ride with no lines. I'm sure Venice and Rome are nice right now without the crowds.

Pedestrian Jul 9, 2020 6:03 AM

Quote:

Originally Posted by CaliNative (Post 8975468)
Should all food service workers and other workers who might be asymtomatic spreaders be tested? Typhoid Mary who was an asymtomatic spreaders of typhoid fever (an intestinal salmonella bacterium spread by fecal contamination) was placed in involuntary quarantine when she kept getting food service jobs and making people sick. Is asymtomatic spread exaggerated?

As many people who routinely come in contact with the public should be tested as often as possible but all the evidence and expert opinion is that food is not a significant venue to spread coronavirus. In other words, you are more at risk from the guy who delivers your food than from whoever prepared it—and if you’re at a restaurant, maybe at more risk from the silverware (and of course the waiter) than from the food.

Typhoid, of course, is a whole different thing because it’s PRIMARILY spread by food and water.

I found this article today interesting:

Quote:

Buffets and Salad Bars, Closed by the Pandemic, Remain Roped Off
By Heather Haddon and Jaewon Kang
July 7, 2020 5:30 am ET

Bad news for fans of buffet meals: It might be a long time until your next one.

Pizza Hut, Ponderosa & Bonanza Steakhouses and other restaurant chains have roped off their buffets to prevent contamination and crowding as they seek to reopen dining rooms during the Covid-19 pandemic. And grocery stores such as Whole Foods Market and Wegmans Food Markets Inc. have kept hot-food bars closed since March, until lately a growing part of the business and a draw for customers. Now, those sales have plummeted given the risk of self-service food . . . .

Health officials have advised suspending self-service food stations because they lead to crowding of customers and repeated touching of utensils . . . .
https://www.wsj.com/articles/buffets...s&page=1&pos=6

In other words, it’s not the food that’s the problem.

CaliNative Jul 9, 2020 6:12 AM

Quote:

Originally Posted by Pedestrian (Post 8975370)
Agreed. Temperature checks are mostly a waste of effort.

If we had the supply available, what we should all be doing is wearing N95 masks that we've tried to properly fit whenever we are indoors. If we did that, I think we could stamp this virus out.

But we don't have enough such masks and not enough people would wear them or pay attention to propper fit.

Incidentally, the most effective N95 for this purpose are the valveless ones because they prevent exhaling virus particles as well as inhaling them but you can accomplish pretty much the same thing by wearing even a thin cloth covering over an N95 with a valve and such an arrangement is probably more comfortable because it causes less CO2 buildup (which gives some people headaches and others claim they feel like they are smothering).

Are you still microwaving your newspapers? I give mine a one minute blast, just before they start to burn. I wonder about cardboard boxes and the air trapped inside. I leave them out for a day in the sun when I get a delivery. Maybe surface spread is rare, but we don't know for sure. I wonder if the air in places like markets is safe? I wear a mask everywhere. Still can't get N95s. The Chinese ones are available but they say some are no good. I have good goggles over my glasses and eyes. Look like I walked out of a Sea Hunt episode.

Pedestrian Jul 9, 2020 6:14 AM

Quote:

Originally Posted by dave8721 (Post 8975471)
I have no plans on going anytime soon (still have to do the kid drop off with wife's 70+ year old parents sometimes) but the only draw would be the fact that it is the one time when everyone wants to stay away and you would actually be able to enjoy it without the crushing crowds for once. Basically just go ride to ride with no lines. I'm sure Venice and Rome are nice right now without the crowds.

They’ve reopened the Louvre in Paris and I saw a video today that made it look pretty crowded.

CaliNative Jul 9, 2020 6:18 AM

Quote:

Originally Posted by Pedestrian (Post 8975473)
As many people who routinely come in contact with the public should be tested as often as possible but all the evidence and expert opinion is that food is not a significant venue to spread coronavirus. In other words, you are more at risk from the guy who delivers your food than from whoever prepared it—and if you’re at a restaurant, maybe at more risk from the silverware (and of course the waiter) than from the food.

Typhoid, of course, is a whole different thing because it’s PRIMARILY spread by food and water.

I found this article today interesting:


https://www.wsj.com/articles/buffets...s&page=1&pos=6

In other words, it’s not the food that’s the problem.

Yeah, I know the food itself is probably Ok. More worried about the cashiers and delivery people who are almost always young and who knows if they could have it and be asymptomatic. Maybe all such contact people should be tested. Many don't wear masks.

Pedestrian Jul 9, 2020 6:19 AM

Quote:

Originally Posted by CaliNative (Post 8975478)
Are you still microwaving your newspapers? I give mine a one minute blast, just before they start to burn. I wonder about cardboard boxes and the air trapped inside. I leave them out for a day in the sun when I get a delivery. Maybe surface spread is rare, but we don't know for sure. I wonder if the air in places like markets is safe? I wear a mask everywhere. Still can't get N95s. The Chinese ones are available but they say some are no good. I have good goggles over my glasses and eyes. Look like I walked out of a Sea Hunt episode.

No. I bought a UV light and attached it to the inside of a large cardboard box. The newspaper and the mask I’ve worn that day and anything else I want to decon goes in there for at least 30 minutes of UV exposure. I realize I’m not eating my own cooking about the risk of surface contamination here but it’s an easy thing to do and since I got a small supply of N95 masks, which can’t be washed but I have to use over and over, I like to zap them with UV between uses.

Regarding N95 masks, they should be fine as long as they are stamped NIOSH approved. NIOSH is the US National Institute of Occupational Safety and Health and they test PPE for compliance with their standards. Many Chinese madks carry their approval and there are lists of approved Chinese manufacturers online. Recently a few Chinese makers were decertified because their masks failed testing but many pass.

SIGSEGV Jul 9, 2020 2:51 PM

Quote:

Originally Posted by Pedestrian (Post 8975469)
Can you point to any legitimate studies that show public temperature checks being in any way effective? My problem with them is mostly that COVID notoriously causes petty high fevers—people feel pretty sick if they feel sick at all. It’s not a thing where somebody would be walking around, going to work etc not realizing they have a fever. So I suspect the number of people with COVID picked up by public temperature checks is vanishingly small. But I’ve seen no scientifically valid studies on the subject.

And a 10% reduction (which I bet is way in excess of what temperature checks accomplish) takes R0 from 3 to 1? Seriously?

Not one 10% reduction, but 10 of them (0.9^10 ~= 1/3). The point is that many small things that are not so painful can multiply to a large effect. Of course there are correlations, etc., but since the infection spread rate is exponential, even small percentages can have large effects.

As for temperature checks, some fraction of people sick with COVID-19 will have high temperatures. One would hope that such people would not go out to a restaurant, but we know that's not the case. So this will reduce the number of COVID-positive patrons by some amount (whatever the fraction of COVID-positive patrons with fevers is). It may not be 10%, but it's more than 0.

iheartthed Jul 9, 2020 3:17 PM

Quote:

Originally Posted by mhays (Post 8975430)
They're not a waste at all. They catch some number of cases, and that's extremely important.

In fact, a series of partial measures is the whole point of everything we're doing.

This stuff is all about odds. Infection rates are about multiplication...for example the infection rate, the number of interactions total, the care taken with each interaction, etc., all multiplied together. Any reduction in infected people walking around will tend to make the equation better, with fewer infections and deaths.

This depends on who is likely to be a spreader. If we are dealing with a virus that is spread mostly by people with no symptoms (either pre-symptomatic or asymptomatic), then temperature checks are useless or maybe even a false sense of security.

Another thing that has come up is that the virus was in different parts of the world much earlier than is widely understood. Some scientists now believe that the virus was in Europe and North America in 2019, but those appearances fizzled out before becoming mass outbreaks. They still don't know why but there is a theory that certain types of people may be super spreaders. The current assumption is that roughly 20% of infected people are responsible for spreading the virus.


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