18 replies to this topic

[Dorian Grey]

In the great mask debate, I've said more than once I avoid people who are talking with loose fitting masks more than I avoid silent mask-less people.  I came to this belief after reading an article on MedScape from Jose-Luis Jimenez, PhD, who argued back in July that aerosols were the primary mode of contagion, & vocalizing a primary generator of aerosols.  (see attached pdf).  

 

Early on, the emphasis was on droplets (cough/sneeze) & surfaces, but the boffins are now saying fooey on fomites (surfaces), and aerosol transmission has moved to the forefront as a primary mode of contagion.  There is also a lot of new emphasis on the size of the initial inoculum, and aerosol that is inhaled deep into the lungs or limited to the upper respiratory tract, and severity of disease.  While we normally breath through our nose while silent, when we're talking, oral inhalation is the norm.  

 

While scientists have measured live virus in the condensate of normal (silent) respiration, apparently this pales in comparison to what occurs when vocal cords, wet with saliva are vibrating rapidly while air is being forced through them.  Fine aerosols are also far more likely to escape from masks (particularly with gaps) and inhaled more deeply into the lungs than droplets, which are likely to hit nasal/oral surfaces during inhalation, resulting in a milder infection.  

 

I feel it is important to have a thread on this, even if it doesn't get much traffic, as what I see out in public is very concerning.  People are chattering away, while standing quite close, often with very loose fitting masks, and family members are visiting each other in their homes, talking the whole time with no masks at all.  

 

This story caught my eye today: https://www.business...-so-much-2020-9

 

A 30-minute conversation may spread COVID-19 more easily than sharing a bedroom. Here's why quiet is a key virus-fighting strategy.

 

"A new study conducted in Singapore found that 30 minute conversations may even spread the coronavirus more than sharing a bedroom with a sick patient."

 

It's a fairly long read, much like the pdf I attached from MedScape, but those who really wish to avoid getting this virus (particularly a deep pulmonary infection) might wish to adjust how they are evaluating potential for contagion in their interactions with others.  I'm all for masks.  Worked as a Surgical Technologist for 35 years, masked all day, but a loose fitting reusable mask with stretched out ear-bands that hangs open at the top is hardly a mask at all.  Please spend a little time on the pdf & linked story, and adjust your defenses accordingly.  

Attached Files

•  AerosolTransmission.pdf   129.03KB   5 downloads

Edited by Dorian Grey, 04 November 2020 - 04:09 AM.

[Florin]

The best way to eliminate aerosol transmission is by using a reusable respirator with P100 filters and wearing some sort of eye protection.

 

[Dorian Grey]

The best way to eliminate aerosol transmission is by using a reusable respirator with P100 filters and wearing some sort of eye protection.

 

 

Agree, a proper respirator is the ultimate in protection.  Have seen around 2 people utilizing this while in public over the last 8 months.  Not something I'd care to wear for too long if there were an alternative.  Simply giving a wide berth to those engaging in conversation would be the next best thing, and probably about as effective. 

 

I'm in California, so always masked (disposable / tri-layer surgical) in public.  I no longer worry so much when I see someone with mask down, quietly drinking or eating.  I use my ears, and change course to avoid those who are chattering away; vocalization being what really generates the aerosols.  If I have to pass someone in close quarters, I take a slightly deeper breath as I approach them, and exhale slowly as we pass.  By the time I take my next breath, we're a dozen feet apart.  

Edited by Dorian Grey, 04 November 2020 - 06:05 AM.

[hotbit]

 

If I have to pass someone in close quarters, I take a slightly deeper breath as I approach them, and exhale slowly as we pass.  By the time I take my next breath, we're a dozen feet apart.

 

 

Funny, I found doing this myself sometimes, but all these measures are such a nuisance.

 

The bigger problem is - do you intend to live wearing masks, preferably P100, avoiding people and in general live in fear and anxiety the rest of your life? In the late spring I wished they would open country and maybe get virus as early as possible in the summer. With 0.5 million cases now found daily, it won't be stopped. Better to contract the virus in the summer as close to now as possible than 5 years later in the winter time.

Long term anxiety may also have negative effect on immune system and possibly person taking preventive steps and living in stress and anxiety for months or years might be deeply stricken after contracting this virus, which may influence inappropriate immune response. Just loose thoughts.

[Dorian Grey]

Funny, I found doing this myself sometimes, but all these measures are such a nuisance.

 

The bigger problem is - do you intend to live wearing masks, preferably P100, avoiding people and in general live in fear and anxiety the rest of your life? In the late spring I wished they would open country and maybe get virus as early as possible in the summer. With 0.5 million cases now found daily, it won't be stopped. Better to contract the virus in the summer as close to now as possible than 5 years later in the winter time.

Long term anxiety may also have negative effect on immune system and possibly person taking preventive steps and living in stress and anxiety for months or years might be deeply stricken after contracting this virus, which may influence inappropriate immune response. Just loose thoughts.

 

As reports of asymptomatic infections rise and death rates subside, my fear has shifted away from the virus and more towards the vaccines, which may become mandatory if you want to travel, go to work or school, and perhaps even leave your home to dine out. 

 

This said, I still hope to avoid infection, particularly a deep pulmonary infection with a large initial inoculum, which can still do a lot of damage.  The knowledge of how this is most likely to occur (close quarter vocalization exposure) has actually been empowering to me.  I'm dining out more often now, outside of course, & no longer fear brief encounters with unmasked strangers, provided they are not actively vocalizing.  

 

A good outpatient therapeutic would be a godsend, & we've recently seen some remarkable study results with ivermectin.  It would be great if they would grant Emergency Use Authorization for IVM, but I'm not holding my breath on this.  I'd also like to see some progress on immune modulation to prevent cytokine storm before I let my guard down.  HCQ still the only immune modulator that does not seem to potentiate infection with early use.  I'd rather not have to be hospitalized & hypoxic before steroids are started.  

 

I'm retired, so perhaps I can comfortably avoid the vaccine for a while, but I still hope to avoid infection until we get some outpatient therapeutics to reduce the incidence of lasting pulmonary or cardiac damage.  Avoiding the jabberwockies & chatterboxes when we can looks like the best way to prevent an unfortunately large, deep pulmonary inoculum.  

Edited by Dorian Grey, 04 November 2020 - 02:56 PM.

[Florin]

Simply giving a wide berth to those engaging in conversation would be the next best thing, and probably about as effective. 

 

I use my ears, and change course to avoid those who are chattering away; vocalization being what really generates the aerosols.  If I have to pass someone in close quarters, I take a slightly deeper breath as I approach them, and exhale slowly as we pass.  By the time I take my next breath, we're a dozen feet apart.  

 

But your strategy doesn't take into account the accumulation of aerosols when there's poor indoor ventilation even when no one's talking much. The vent system could also be spreading the stuff around with no one in sight. And you constantly have to be on your guard for talking people. Maybe if you don't go out in public that much, the risk and the constant vigilance would be acceptable, but this doesn't sound like a good strategy for longer periods of exposure or if there's a lot of people around.

Edited by Florin, 04 November 2020 - 06:33 PM.

[Florin]

The bigger problem is - do you intend to live wearing masks, preferably P100, avoiding people and in general live in fear and anxiety the rest of your life?

 

If you wear a respirator in public, you don't need to avoid anyone. There's no need for fear or anxiety. And as a bonus, you won't get colds or the flu either. If everyone wore a respirator, all of this would be over in a few weeks without the need for any magic concoctions or lockdowns.

[Florin]

Under some circumstances, there's medium to high risk of transmission even when everyone is silent and wearing masks.

 

 

Two metres or one: what is the evidence for physical distancing in covid-19?
https://doi.org/10.1136/bmj.m3223

Edited by Florin, 04 November 2020 - 06:56 PM.

[Dorian Grey]

I'll agree, simply avoiding vocalizing people is not 100% effective 100% of the time, but I'll also posit, aside from wearing a respirator, simply avoiding vocalizing people will always reduce your risk of a large inoculum of aerosol inhaled deep into your lungs, compared to the exposure you might get joining a group in a jabber-fest.  

 

If we consider inhaling a large inoculum of aerosol deep into your lungs as most likely to cause severe disease as opposed to a minor exposure resulting in mild or asymptomatic disease, I'll take the latter any day.  A minor exposure might also help avoid a mandatory Warp Speed vaccine if this is a concern.  

 

I've become quite fearless about going out & about now that I've learned how to avoid a large inoculum and resulting severe disease.  We have an indoor mall that I used to like to visit for lunch.  Avoided it for many months, but have recently returned.  Any minor exposure I get from widely dispersed aerosol is unlikely to land me in hospital, but just might seroconvert me to positive antibodies and natural immunity.  However long the immunity lasts, I can't help but think this might be safer than the Warp Speed vaccine.  

 

Time will tell!  

[Mind]

Can we all agree now (considering the aerosolized transmission) that all of the current mask mandates and the face coverings are not helping things?

 

I looked at the data from so many states and countries and it seems obvious that the current mask mandates are CAUSING increased spread (except in a couple of outlier SE Asian countries and monolithic culture/island nations). It is happening in my state as well. When there was no lockdown and no mask mandate, but people were asked to be careful (take precautions if you are vulnerable), the spread was slow. The mask mandate went into effect and POW, now the spread is higher. 2 months of the mask mandate (and good compliance) and the case numbers continue to rise.

 

Fauci, et al, were correct in the beginning, that regular people should not be using masks because they are not going to use masks properly and will start mingling in close quarters too often, thinking that they are protected. They constantly touch their masks. The (generic) masks are probably a significant vector for transmission, IMO, although I know some would disagree.

 

I also mentioned in the other thread that if everyone was wearing a respirator and hazmat suit, then transmission would be near zero, but that is not realistic. Currently, countries are unable to even provide N95 masks to all of their health care workers.

 

Considering the aerosolized transmission, I think a more comprehensive approach is needed. Protect the vulnerable - use the testing for them. Focus on treatments. Young healthy people (under 70) keep the world running.

[Florin]

No, masks still work. Even with imperfect mask mandates (no bans on indoor restaurant and bars and different households mixing without masks, for instance), there's little excess deaths, and this might indicate that masks are producing a kind of herd immunity (which isn't ideal but at least the vulnerable won't actually die). Another explanation for the increase in cases is that the virus is supposedly more contagious than the viral strains affecting Asia. Yet another factor might be that the masks worn in Asia, which seem to be either surgical or KN95, are better than the mostly cloth masks which are worn in the rest of the world.

 

And for the millionth time: there's no way practical way to protect the vulnerable without mask mandates; the vulnerable would either need to "voluntarily" lockdown or they'd just get a higher dose of the virus and have a more severe form of C19. Testing doesn't change this one bit.

 

Respirators are very practical, and no one needs a hazmat suit. If they were widely available, there'd be no need for mask mandates or lockdowns (voluntary or otherwise), but the idiots-in-charge aren't recommending them and this leads to not enough demand to justify expanding supply.

Edited by Florin, 05 November 2020 - 11:46 PM.

[Dorian Grey]

My 2c worth regarding the masks is, they do seem to instill a false sense of confidence & security.  I see people out in public talking with strangers standing 2 feet apart.  They seem to think "we're both wearing masks so it's all good, no distancing at all necessary".  I've also had store employees walk right up to me and start jabbering away.  I step back & they step forward, I step sideways & they follow suit.  Stand back dude, I can smell what you had for lunch!  

 

This said, I don't mind wearing them at all.  Wore one at work for 35 years.  If it will keep the peace, so much better.  I did hear a lecture (youtube) where the guy compared vocal aerosol to cigarette smoke.  He said any mask that wouldn't stop a lung full of smoke isn't going to contain aerosols.  I imagine even a poor mask would deflect aerosol containing breath to escape to gaps above, below and to the sides of the mask, where it may disperse better rather than creating a dense cloud right in front of your face as you're speaking with someone.  Don't really see how wearing one could be dangerous to the user, but again, masked people seem to have no fear about abandoning social distancing.  

[Hebbeh]

Dorian Gray,

 

You having been a surgical nurse for 30 some years, what would your professional opinion be on the long term patient outcome if nobody on the surgical team was masked?  Would unmasked surgical teams have any adverse effect on patient health over the long haul?  Did you ever work with a surgeon that was lax with masking or pulled his/her mask down during surgery because masks are an unnecessary nuisance?  If so, did you witness any trends in regards to higher patient complications?  What is the official health industry's position on mask usage around at risk patients?

 

Thanks! 

[Dorian Grey]

The nurses are all very strict about masks in the OR, & they would pounce on anyone (even a doc) who tried to briefly set foot in the room without a mask while a sterile field is open.  Sometimes the anesthesiologist will smuggle coffee into the room and will pull their mask down for a sip a few times during a case while the nurses back is turned.  The surgical team (surgeon, assistant & scrub) all wear sterile gown & gloves so we can't touch anything above our nipple line.  No nose scratching, mask adjusting or itching anything.  

 

Surgical infections are a most unfortunate complication following routine surgery, & the mouth contains a lot of bacteria that can infect open wounds, so compliance with aseptic technique is a badge of honor, though there are some surgeons that need encouragement from time to time.  There's very little risk of surgical wound contamination from the nose, & in England & Europe, surgeons would often wear their mask under their nose, simply covering their mouth. This practice has vanished in favor of full coverage, though you may see this in old movies.  

 

We have special precaution protocols for patients with MRSA, TB & now COVID, where N-95 masks are worn.  The surgical team usually isn't affected all that much, as full protection is the norm for all scrubbed personnel.  Interesting thing about being a scrub is that you never know what happens to the patients once they leave your OR.  The next patient will be arriving in less than an hour.  

Edited by Dorian Grey, 06 November 2020 - 04:17 AM.

[Dorian Grey]

Aerosols in the news: 

 

https://www.dailymai...eading-air.html

 

Covid is evolving 'to become better at spreading in the air': Scientists find Alpha-infected volunteers exhale up to 100 TIMES more virus than people who caught original Wuhan strain

 

Note an interesting clue within the text about how aerosols are generated: 

 

"Participants breathed into a machine called a Gesundheit-II for 30 minutes without wearing a mask and 30 minutes while wearing a mask"

 

"Volunteers were either asked to repeat the alphabet three times while taking part in the study, or sing 'happy birthday' three times"

 

---------------------------------------

 

Why talking or singing?  Because you generate far more measurable aerosols from vocalization than from normal breathing.  

 

Florin's post above seems to indicate normal breathing can generate some aerosols, but from the chart in his post it is clear, vocalization is what generates aerosols in great volume.  In the new study I linked to, it appears they didn't even attempt to measure aerosols in normal breathing...  WHY?  Doesn't seem like it would have been that difficult to add this.  

 

What's the big deal?  I can't help but notice masked people chattering away in close quarters with strangers, like their masks are some kind of magic shield.  From the study: "when wearing a mask, infected people exhaled 48 per cent less of the virus".  Oh, half as much.  Does this mean masked people do not produce infective aerosols while they are in a contagious phase?  Not really, but it seems clear they are most contagious when vocalizing!  We've already seen simple masks are not substantially protective to the wearer against aerosols, so I doubt you'd get an additional 48% reduction from your own simple mask.   

 

Haven't seen a lot of reliable data on indoor aerosol dispersion with distance.  We've heard of super-spreader events in churches (substantial vocalization / people sitting close together for an extended period of time), but little regarding a contagious person contaminating the air of an entire indoor mall just by breathing while walking through it.  

 

I'm still going face naked while out & about, using social distancing to avoid the 'rona, but I'm particularly conscious to give the chatterboxes a wide berth, whether they are masked or not while indoors.  That maskless guy quietly sipping coffee isn't going to get you sick.  It's vocal interaction with strangers in close quarters where risk is greatest, and masks only provide limited protection.  STAND BACK!  It's distance that will keep you safe.  

[joelcairo]

If you look at the data, N95 masks are extremely effective, vastly better than cloth masks. I don't know why there isn't more of a push to get people to use them. There doesn't seem to be a shortage -- I don't see them very often in stores, but they can be ordered online without much trouble.

[Florin]

If everyone wore N95s, they'd be effective due to their ability to prevent the accumulation of aerosols (despite the generally poor fit they provide).

 

But that's not going to happen, so you're better off wearing an elastomeric respirator or even a DIY PAPR.

 

Why isn't there a push for more effective PPE? Because people like Fauci think it'll eat your face off.

[joelcairo]

I'm sure the fit is important, but the worst fitting N95 mask is likely to be better than the best surgical mask or cloth mask.

 

I wear glasses and I especially like the metal tab that can be squeezed to make a tight fit around the nose. Other masks instantly cause my glasses to fog up, suggesting that the mask might work as a sneeze guard but there's not much air filtering going on.

 

 

[Florin]

If the choice is between masks and disposable respirators, better protection is only sometimes offered by N95s. Some poor-fitting N95s are no better than wearing surgical or cloth masks. Another poor-fitting N95 (Aero Pro AP0028) can provide almost zero protection, which is worse than even a cloth mask. 

 

https://doi.org/10.1...ne.0245688.g004

https://doi.org/10.1...ne.0245688.g003

 

Since more effective and comfortable PPE is available, why would anyone want to gamble with N95s? Plus, there's no need to worry about adjusting nose wires.

 

https://www.ncbi.nlm...BK540078/#effi1
https://www.doi.org/...urg.2020.05.022

https://www.doi.org/...1/jama.2008.894