> If the neuroinvasion of SARS-CoV-2 does take a part in the development of respiratory failure in COVID-19 patients, the precaution with masks will absolutely be the most effective measure to protect against the possible entry of the virus into the CNS. It may also be expected that the symptoms of the patients infected via facal-oral or conjunctival route will be lighter than those infected intranasally. The possible neuroinvasion of SARS-CoV-2 may also partially explain why some patients developed respiratory failure, while others not. It is very possible that most of the persons in Wuhan, who were the first exposed to this previously unknown virus, did not have any protective measure, so that the critical patients is much more in Wuhan than in other cities in China.
This is a good example of why writing off COVID-19 as no more dangerous than the flu is itself so dangerous.
I should also point out that most people in the US face similar conditions to those in Wuhan. The extent of infection is not known, and therefore protective measures are not in place. We have been actively discouraged from "buying masks" and told that they are ineffective.
Yes, only a N95 or better mask would protect you from incoming, as opposed to outgoing, viruses, and these masks are both impractical for everyday wear and need to be conserved for public health users.
I think that different sources are using different definitions of "effective" here. If a simple surgical mask cuts down transmission rates by 50% that isn't anywhere near good enough for health workers working with sick patients every day. But it might still make a significant improvement in your chances of getting infected and, combined with social distancing, might drop the R0 below 1. Hence why Chinese and Korean authorities are encouraging everyone to wear surgical masks but the CDC saying they're ineffective.
I completely agree. Even having a mask that only results in a 20% reduction of transmission could be the difference between a growth factor that is less than 1, vs a growth factor of greater than one. It could be the difference between taking off or halting.
I suspect that even a spare cotton t-shirt material affixed over the face would stop a significant amount of droplets from transmitting.
It would be worth researching the effectiveness improvised masks, at the very least.
The problem is that a mask that isn't regularly replaced and handled very carefully actually increases your chances of catching the virus, via a mask->hand->face transmission.
Is there data or a study that says that risks increase from using masks poorly? I’ve looked into the literature and everything I’ve seen says they are significantly protective in real-world use.
The masks encourage a warm moist environment surrounding your nose and mouth.
If the mask becomes contaminated, it becomes an ideal vector for encouraging infection -- so if you touch the inside of the mask with your contaminated hands (say you move the mask to touch your face or adjust it or whatever), for example, the mask becomes the opposite of protective.
Masks are somewhat effective at reducing spread if the already-infected person is wearing the mask.
Which part of this is being made up? That improperly fitted mask isn't protective? That unless you very carefully handle a mask when taking it off, you'll transfer the contaminants from it onto your hands and/or face? That people compensate for risk[0]? That those masks are disposable and lose their protective power over short time (hours)?
Yes. Do you have a study that shows that a mask that has not been fit tested either provides no protection or actually increases the overall risk to the wearer?
I have looked at a fair bit of research on masks lately, and everything I've seen is that they are significantly protective, and, for example, reduce your risk of catching SARS by about 70%.
Yes, if a mask doesn't fit properly, some air will come through the sides. Even in that case though, the mask is still filtering some air, and it's protecting you from touching your mouth or nose, and it's protecting you from droplets hitting your mouth or nose from being coughed or sneezed on.
TL:DR:
The most effective use of disposable masks for blocking germ transmission is by the people with the germs who might pass them to this without but at risk.
Surgical masks are meant to protect surgery patients from the medical staff and the droplet-encased germs they emanate. N95 masks are meant to protect the wearer from particulate matter (harmful dust) in the air, specifically those particles over 30 microns. SARS-CoV02 is roughly half the size, so as an aerosolized virion, as opposed to droplet-suspended virions, they may have limited effect. N95 masks also often come with exhalation valve releases to improve inhalation fit - so exhalation pressure does not break the seal around the sides. A sick person wearing a mask with a valve that releases right in front of their mouth may be better than no mask, but it is a potential bypass for droplet suspended virions.
The US just doesn't have the culture where everyone puts on masks during flu season, like some places (HK for one), and that level of herd usage is really what might be likely to slow transmission to a breakable rate.
What I've read about Coronaviruses is that most transmission is either through hand to face contact or droplet-suspended virions so a mask that doesn't protect against aerosolized droplets would still be fairly effective. I understand that surgical masks aren't intended to prevent inhalation of droplets but the substantial symmetry between air passing through one way or the other would suggest at least broadly similar effects either way. Given the empirical results from elsewhere in the thread it seems like that may be the case.
Are surgical masks sealed around the edges? I've only worn N95 before and if you don't have a proper seal you're not even filtering the air. That's what I've always assumed was the problem with surgical masks. It's not that they're not a good enough filter, it's that they aren't even filtering the air when you breath in. But I might be wrong.
> N95 masks are meant to protect the wearer from particulate matter (harmful dust) in the air, specifically those particles over 30 microns. SARS-CoV02 is roughly half the size, so as an aerosolized virion, as opposed to droplet-suspended virions, they may have limited effect.
The N95 filters are tested with particles at 30 microns, but that doesn't say anything about their effectiveness against other particles.
3M, naturally, has released some information on this exact topic [1] which goes into a fair bit of detail on the various methods by which masks effect filtration. The tl;dr version is that there are several ways by which filtration is achieved that generally overlap and work towards providing effective protection well above and below 30um. There is generally a small dip in the transition between two primary methods which creates a specific size range where filtration is less effective.
Whether that's an issue depends on your definition of "limited effect". For the masks they tested, that dip generally occurred around 0.04-0.1um. Even in the worst case scenario, however, the worst masks tested were still filtering ~94% of the particles (in a mask that only claims 95% effectiveness to begin with). The linked document has coronaviruses listed as being about 0.125um in size, which has them falling toward the end of the dip where the mask is trending back towards 100% efficacy.
(For what it's worth, they also have the distribution of droplet sizes in a sneeze and they are all smaller than 30um as well. However they're still in a range where the mask will be about 100% effective.)
Which is all to say I certainly wouldn't describe an N95 mask as being of "limited effect".
And as to that not our culture comment, I mean it's the American of course who got told to isolate himself on suspicion of infection but decided to go to a group political event across state lines regardless, only to infect at least one other person and lead to further isolation calls for everyone else he came into contact with.
I'm not sure I would call them impractical for everyday wear. I wear N95 masks when commuting during active wildfires. The news always says not to wear them because you won't put them on properly, but it's really not that hard to ensure the fitment is correct. It's not like the construction workers that wear them occupationally are rocket scientists.
My partner is more vulnerable to respiratory problems and has always worn N95 masks when in public during flu season. What's changed now is she gets all kinds of shit from people because they think she somehow hoarded masks away from healthcare workers. We've had boxes N95 masks for years, but now we're assholes for hoarding...
Telling people they should wear masks because they don't put them on properly is like telling people they shouldn't drive cars because some people drive them into trees.
I think what OP means is N95 masks must be properly fitted to the individual. When my wife started working at a hospital she had to undergo such a fitting. So unless you get the proper size, you could still be exposed. I think that’s what he meant.
> N95 masks must be properly fitted to the individual.... So unless you get the proper size, you could still be exposed.
I'd really like to know how often those fit tests actually result in someone needing to select a different respirator size or style.
I wonder if they're only needed if you're required to be 100% sure all your people can use their respirators with near-100% effectiveness. That's probably necessary if you're working in a contagious disease isolation unit or removing asbestos all day every day, but maybe not for less dangerous environments.
Looking at the current infrastructure and the current investment in said infrastructure. I think it’s a safe bet to go out 30 years or more before self driving cars are the norm.
In cities sure. Rural areas not happening. Add the fact people like to drive to Mexico Canada and Alaska I’d call it a non starter.
Example. I have a place where the road on google maps and the place people drive vary because rural Arizona uses washes as roads. Cars driven by humans get stuck.
A lot hinges on whether one considers level 4 or level 5 to be "self-driving".
I wouldn't want to own a car without a steering wheel, sometimes you have to do weird stuff like park on a specific patch of grass at a rural wedding and it's going to be easier to do that myself than try and convince a robot.
But a car that can a) handle 'most' driving for some value of 'most' and can b) safely hand over or come to a stop under basically all circumstances including a sleeping driver? That's actually a much simpler task and it's a very useful vehicle. I would want one of those even if I lived somewhere where road conditions were such that I had to steer it myself on a daily basis.
Like in Arizona, once you got to paved road you could enter an address in Phoenix and kick back in actual safety, without having to worry about taking over at a moment's notice. I think that's achievable in 10-20 years, and it could be less.
I wouldn't say it's a certain type of people ("some people" vs. "sometimes people"). You could argue for it, though seems like a hard argument to push.
Cars are inherently dangerous, because there isn't a reasonable guarantee that something will not go critically wrong (as opposed to, say, a train). Also, when driving a car, you're not only betting that you won't make a mistake, but also that someone else won't make a mistake (that would affect you).
Occupationally I'm a diesel mechanic,so I suppose I could be lumped into the non occupational rocket scientist category. Im learning python.
Yes, we wear n95, but we also get OSHA/niosh specific training on fitment, changing, PPE exposure limit, and appropriate environments. You do not. What people are hoping is that an industrial particulate mask is going to somehow prevent the flu or corona, which honestly I have never understood. Wearing a mask while pressure cleaning a paccar12 engine? Yes, you don't want fine grease mist in your lungs. Powder coating something? Better mask up. Wearing it for a fire? Yes, but change it out once or twice a day and check it often. The flu? How?
I used to be a residential painter. AIUI (and I could be wrong here) biological and water-based molecules are larger than other chemical molecules so can be stopped by the particulate mask. This is why you can wear a dust-cup when spraying with acrylic (water-based), but need a respirator for oil or lacquer-based paint.
TBH I'd expect the n95 to work better for infection than a surgical mask because you can get a better seal to your face
> I'm not sure I would call them impractical for everyday wear. I wear N95 masks when commuting during active wildfires.
Right on. For the past couple of years, because the Seattle summers have been hazy due to the wildfire smoke, I still have quite a large batch of N95 masks. I too used to wear them during my commute and the only problem I see is that if you're at risk (underlying respiratory/heart problems) you'll not be able to tolerate the mask... With a good fitment, it makes it harder to breathe.
I think it's unfair to label people hoarders for having these masks... After a couple of consecutive years of wildfire smoke, I think this is the new normal and everyone should have them. It's not my problem that the healthcare industry has a supply issue with these masks, they should have a different, hopefully more efficient and preferential supply chain. I hope they don't buy them from Home Depot (where I got them from).
I was under the impression that there isn't (yet? But not even close to) a supply issue for the healthcare sector, but rather only at retail, due to a combination of increased demand and supply switching over to for-healthcare-only mode.
This will be something that's routine, just following the plan, that exists to serve some combination of regulation, duty, and risk (burning important healthcare customer or government relationship) mitigation.
Regular surgical masks won't protect your from inhaling the virus, but they will protect you from rubbing your face and nose 100 times a day with contaminated hands, without even noticing it. I wouldn't dismiss their efficacy.
Bank customers in bandanas would probably be a good way to get shot by a security guard in a bandana. The days of Butch and Sundance aren't that far behind us!
Many places small and large put a large value on butts in seats.
For a less cynical take, there's a lot of conversations that do happen more efficiently in-person, particularly at a lot of places that aren't set up for "full remote".
It's sometimes seen as a security issue, especially if you are not provided with a company-issued laptop. Or your work may require specialized equipment like beefy machines for 3D rendering or local access to a server.
I think there's a legitimate question here. Intuitively, if a non-N95 mask only stops 25% or 50% of incoming viruses, that still seems helpful? It's worth noting that in countries where wearing masks is normalized, making sure the general public can get some is a top priority.
On top of providing some limited protection of the wearer, it also works like herd immunity in that if everyone wears them, then those that don’t yet know they’re sick are reducing their spread.
At the moment because of the misinformation people wearing masks are being mocked and chided in public and its really unhelpful. Especially since there are immune compromised individuals and individuals with other conditions that really need to take every precaution they can, including that 10% reduction a surgical mask may give them.
My layman's understanding is that any barrier will stop some percent of most things. In the case of small, airborne particles, this stopped percentage of already-dry, floating material is very small. That means inhaling through them is relatively ineffective at stopping you from inhaling the particles.
When you exhale it is more wet and the moisture causes the barrier to catch more of the airborne particles. The barrier also catches any more-solid material that would otherwise land elsewhere, providing a mechanism for the particle to spread.
This means the net gain for wearing them to keep from catching the disease is relatively small compared to the gain by wearing them to prevent the spread if you may have been exposed.
I would agree if everyone exposed wore masks the spread of this contagion would be reduced considerably.
Logically, I might extend it to everyone wearing masks would considerably reduce the spread of exhaled contagions. This might first be encouraged in high population density areas, like parts of Asia, and first need to be integrated with fashion[0] to have any chance of broad success. I suspect it will never be a preference everywhere barring some sort of serious consequence (like death) for not wearing the mask.
In this situation, I think the most important thing is to know that normally available or homemade masks are helpful for presenting the spread of the disease. The more expensive masks are better but in this instance, not better in a meaningful way for the average person. The current supplies should be saved for those at-higher-risk populations like medical staff.
I will argue this is wrong: Only N95 or better masks have studies proving their effectiveness. I don't think we have good data on weaker masks or even "home made" masks- It's totally possible they are also effective, with proper technique.
Please somebody show me data that proves otherwise, I'm totally open to it. (Note: I'm not saying I want you to post opinions from people in authority, I'm saying I want to see data)
No, there is a 2009 study which compares N95 mask efficiency with surgical masks, because they predict that during a pandemic N95 masks will be in shorter supply. (1)
They don't find significantly more efficiency for N95 masks, but other studies do find N95 masks slightly better. (2)
Even a simple homemade mask has some efficacy [1] though it significantly less. The primary author’s summary of wether they would be protective is “no” [2]
> Quality commercial masks are not always accessible, but anecdotal evidence has showed that handmade masks of cotton gauze were protective in military barracks and in healthcare workers during the Manchurian epidemic.
> The prototype mask achieved a fit factor of 67 for 1 author with a Los Alamos National Laboratory (LANL) panel face size of 4, a common size. Although insufficient for the workplace, this mask offered substantial protection from the challenge aerosol and showed good fit with minimal leakage.
One of my coworkers, who is a staunch supporter for wearing face masks to protect against coronavirus, wears an N95 the entire time he's in the office. Yesterday he claimed he's having chest discomfort (which is what some people will feel when they wear N95 24x7 awake) and went to a hospital to demand a test for coronavirus infection. Needless to say his request got declined and he's doing just fine but I am simply speechless at the irony.
Meanwhile in South Korea everyone has masks. In WWII we built one bomber an hour at one plant, and now we can't figure out how to build millions or billions of masks.
Multiple companies in the US, China, and Europe have announced that they will be producing millions or more masks a month with availability beginning as soon as next week, just 2 months after the virus went global...
It took most of the war for that plant to get to the point of building a bomber an hour.
Even N95 masks are not fully sufficient. They typically block particles at 0.3 microns or larger, but coronaviruses tend to be smaller, around 0.1 - 0.3 microns.
You need an ASTM Level 2 or higher surgical mask to block coronavirus from completely penetrating the mask.
That said, any mask is better than no mask, first because it prevents you touching your mouth and nose with potentially infected hands, and second because coronavirus travels in water droplets which can be stopped by the mask from going straight into your mouth or nose.
Yes, the virus itself is small enough to get through, but typically the virus comes in a water droplet (as in being coughed or sneezed out) and those will be mostly stopped by an N95 mask.
Hmm. Based on what I read, particles smaller than 0.3 microns have a widely "wandering" path of travel through the mask fibers on account of Brownian motion. My understanding was that 0.3 micron particles are the size that the N95 mask is least effective at blocking. Smaller particles are blocked more effectively, not less, until you get down to a scale so small that you pretty well exclude live biological material.
I think we should all ask ourselves why we take it for granted that we should simply have to ration masks. Why aren't there enough masks available for everyone for inevitable outbreaks like this? Why don't we have the industrial capacity to manufacture masks in the US, leaving us reliant on foreign imports?
We spend ~$80 billion dollars a month on our endless war, military and spy agencies in the name of "national security", but I'd argue that having ample medical supplies (and the ability to manufacture them) are just as, if not more important, to our "national security" as the vast majority of our military activities. Hopefully this crisis will not become to severe and will serve as a wakeup call for us to rethink our national priorities before the next inevitable crisis.
There was an article recently about an US mask manufacturer (small one, not 3M), which for years warned that this will happen: a pandemic will hit and there will be a severe lack of masks anywhere.
He also recounted how after the 2009 flu scare everyone was telling him how after it ends they will now stockpile masks to be ready for the next one, he increased production, but then was stuck with it because people stopped taking his calls the moment the flu faded.
> Why aren't there enough masks available for everyone for inevitable outbreaks like this?
I don't know anyone who has conclusively demonstrated there are not. What we have right now are runs on Home Depot and the like buying out respirators and dust masks faster than the stores can restock them.
> Why don't we have the industrial capacity to manufacture masks in the US, leaving us reliant on foreign imports?
We haven't and aren't. 3M manufactures their masks in the US.
It comes down a question of priorities - the money is being spent right now. Is the average American better off if we spend $25 billion dollars next week arming Turkish Jihadists and sending missiles to Ukraine, or spending that money to build up our own country and respond properly to this outbreak before it gets out of control?
> The study reported 'no significant difference in the effectiveness' of medical masks vs. N95 respirators for prevention of influenza or other viral respiratory illness.
I have a small box of N95 masks in my shop - bought last summer for dust protection. When is the right time for me to put them on my family. Part of this is how long will they last before I must replace them. Or should I put them on eBay for a million dollars and hope I life to enjoy my new found wealth?
Surely you have elderly friends and relatives, give each one one of your masks (once things are dire enough that people will actually learn to use masks properly and not waste it.)
There isn't a shortage if you're a hospital. There's a run on the retail supply, and retail restocking will be very limited, if at all. But your local hospital is fine.
And it would have to be apocalyptic for them to accept a box of medical equipment from some guy wandering in.
I've used them a fair bit at work, you get used to them. Proper fit is important though, and many people with facial hair will need to remove it before the mask will be effective.
It's almost a moot point right now though because they're sold out pretty much everywhere.
This is NOT true. N95 is needed for health professionals in an active care environment. THIS DOES NOT IMPLY MASKS in general ARE NOT EFFECTIVE for individuals in public spaces who may run into someone who’s infected.
This is super scary. Before I read this I was happily thinking hey it's no worse than flu. Now... I'm wishing I didn't live in a huge city riding the subway daily.
Learning about the mechanism by which it kills shouldn't change our estimates of the lethality of the disease. We already knew that for most people it was just a bad flue but a noticeable fraction of those infected needed to get to an ICU. Now we just have a better idea of why.
I keep trying to not look up Coronavirus news online, but I can't help it... and after reading this I'm genuinely terrified. The word "potential" on the title is entirely invisible to me.
Oddly enough, I was on the "pandemic" bandwagon early enough that my period of anxiety and insomnia has now passed already. People get used to new states of affair pretty quickly.
Mortality rate of covid19 for people with cancer is estimated at over 6%. My mom has cancer. Every person who gets covid19 but thinks "oh it wasn't that bad" makes it just a little more likely that people like my mom will contract it.
The reason to not panic but be prepared is that humanity has zero immunity to this virus, whereas there's lots of group immunity to influenza. I'm not sure why it's so hard for people to see the issue here.
It's significantly more deadly than the flu. But also, people should probably take influenza more seriously anyways.
China also had some pretty extreme measures to get their low number of cases, measures I don't think will play out too well in the US. And probably won't have a full count yet.
We can hope for the best, we can wash hands etc., but it's not unrealistic to say this can get bad.
The rates in China are dropping because they have some form of travel restrictions for 780m people. If those restrictions would be removed, the rates would go up immediately as seen before and now in other countries.
You can't compare absolute deaths between the flu and WCV.
The flu infects nearly 20% of the world's population each year. Estimates by the NIH are 10-20% annually in the US, and those numbers are probably similar in other countries. China has a billion people, so that means the flu infects probably 200 million people each year but only 130,000 die. The death rate is below 0.2%.
In contrast, only about 90,000 people have been infected with WCV so far. Thousands have died. The death rate is at 3.8%, or roughly 19-20x higher than the flu.
Have you considered the fatality rate and what would happen if it reaches the same percentage of population as seasonal flu?
Check out Spanish Flu for worst case scenario.
China restrictions have been much more stringent than what you imply. People in Wuhan were prevented from leaving their apartments at all and needed to wait for food from the government.
The jury is still out whether softer forms of restrictions can work once the disease is widespread. We will see about that by watching South Korea and Italy. (We know it works if there are not too many cases around, like in Singapore.)
This makes zero sense. We know the fatality rate. We know the R0. We know how many people have it currently and how fast it’s spreading. It’s simple math.
It's not clear that it spreads via aerosols, in fact it's more likely that it spreads via droplet and contact. Thus the virtue of the mask is that it keeps the individual's fingers away from their faces. From the perspective of the theory in the article, masks keep people's fingers out of their noses. Of course, there are other ways to do that.
Wuhan was infected at the worst possible time (CNY) where the entire population underwent a systematic distribution of the virus (visiting relatives) and also likely bodily fluid exchange (via sharing food - Chinese people don't use communal utensils with family).
Ok, but is brain tissue uniquely infectable compared to eye tissue or something? The ultimate worry isn't that your olfactory bulb gets hurt, it's that the infection reaches deeper into the brain, and I don't get why it's easier to do that from the olfactory bulb rather than from the eye.
When you have an infection around the nose area you'll be immediately put on strong antibiotics, because the danger of the infection spreading to the brain through the nose is so big.
Yan-Chao Li [etal.] ABSTRACT
Swine hemagglutinating encephalomyelitis virus (HEV)
has been shown to have a capability to propagate via
neural circuits to the central nervous system after pe-
ripheral inoculation, resulting in acute deadly encepha-
lomyelitis in natural host piglets as well as in
experimental younger rodents. This study has system-
atically examined the assembly and dissemination of
HEV 67N in the primary motor cortex of infected rats
and provides additional evidence indicating that mem-
branous-coating-mediated endo-/exocytosis can be
used by HEV for its transsynaptic transfer. In addition,
our results suggested that this transsynaptic pathway
could adapted for larger granular materials, such as
viruses. These findings should help in understanding
the mechanisms underlying coronavirus infections as
well as the intercellular exchanges occurring at the syn-
aptic junctions. J. Comp. Neurol. 521:203–212, 2013.
that doesnt seem to be the case. this virus really likes your lungs because of a specific protien. this protien exists in your lungs at a greater concentration than elsewhere in your body. The virus would have to undergo a specific series of mutations to get good at targeting neurons.
yes, but there isn't a direct route from the outside to your brain. Your eye socket is relatively well insulated from the outside by skin, connective tissue, conjunctiva.
what you should take home from this is that you are not in immedate danger from a neurotrophic virus at this time.
what you should also take from this espescially if you are involved in policy is that this corona virus we are experiencing has in its distant heritage ancestors with reported neurotrophic properties. It is possible, that at some time in the future, this virus will accumulate signifigant genetic drift and gain or lose certain properties.
> It may also be expected that the symptoms of the patients infected via facal-oral or conjunctival route will be lighter than those infected intranasally.
Why not use a cheap noseclip for swimming? Perfectly leak-free. The paper suggests intranasal transmission is what you most want to avoid.
> It may also be expected that the symptoms of the patients infected via facal-oral or conjunctival route will be lighter than those infected intranasally.
Self-infection is very plausible. Once someone has it in their body, some minor action can transfer it from one organ to another. No one can stay vigilant of their own body 24-7.
> I should also point out that most people in the US face similar conditions to those in Wuhan. The extent of infection is not known, and therefore protective measures are not in place. We have been actively discouraged from "buying masks" and told that they are ineffective.
Not exactly. I'm hopeful that differences between the typical American lifestyle and the typical Chinese lifestyle will help make the epidemic less severe in the US.
Americans are more "spread out" than Chinese: we often drive personal cars instead of taking public transit; our homes are freestanding with more private space per person; our public spaces are often less crowded, etc. I think open offices are even more common in China. Hopefully that extra distance will help.
This suggests an advantage to purposeful infection by oral/eye rather than accidental by intranasal. It'll be interesting to see what the case fatality rate is when segmented by infection route.
It's been suggested to me, in addition to hand washing, to use soap to rinse a bit of my nostrils. Not sure if it makes any difference at all, but I've been doing it on the off-chance.
I would think this would actually increase the odds of infection via that route since it would tend to dry out the skin in your nostrils and remove some of the natural defenses we have there.
Yeah probably reduced, but it may be more to do with them becoming contaminated. The link points to a study saying
> One study found that nurses averaged 25 touches per shift to their face, eyes, or N95 respirator during extended use.
How problematic that touching is probably scales with how problematic your environment is. They're pretty sponge-like. Wearing a surgical mask over an N95 would help a lot.
In a controlled biosafety level 3 lab, "single use" things are definitely the most common, where everything exposed to the outside world is destroyed after you're done. What's worn underneath is washed and you're forced to take a shower. So that's what you do if you know you're in a contaminated environment – not sure what I'd do in a public place.
> Yeah probably reduced, but it may be more to do with them becoming contaminated.
How effective is the virus after the mask has been unused for a while (so "cold", like a doorknob or a desk)? If it is not, the mask should be good to go then, doesn't it?
I gather that it's too early in understanding COVID to have robust answers to this sort of question.
I use a reusable mask, and honestly, I don't wash it very often. It's there mostly so if I absentmindedly touch my nose I don't actually touch my nose, and so I never remove it until I've thoroughly washed my hands.
No idea but some people (whose source I don’t know) say the virus can live on some surfaces to nine days. Guess one could use sterilants/disinfectants to accelerate that time dramatically.
This! It really boggles the mind that officials would discourage wearing masks (even surgical masks). You see, the best way to stop COVID-19 is to thwart its infectious potential. And this is done by two things: everybody wears masks (since nobody knows they are contagious until it's too late) and everybody washes hands constantly. But nooo, no need to panic, this is not Asia, this is The West... Freedom!... x_x
Can someone shed some light on the difficulties of producing the "simple" surgical masks? I'm not talking about something that filters the incoming air, but the lame kind that just reduces the amount of liquids you disperse when breathing, coughing, sneezing etc.
Are they so high tech you can't just ramp up production? And how many months in advance would you need to ramp it up? We're about 3 months in and nobody got the idea to increase production of masks until about a week ago (similar for hand sanitizer, soaps etc)? What am I missing, why is that a thing?
Demand is probably relatively (to other products) stable, why would you have been running a factory with unused capacity available to ramp up into for years ?
I read about a hand sanitiser manufacturer ramping up in the UK; by increasing hours, not throughput. And obviously to increase hours you need more staff, training, and maybe to review some policies, local bylaws, and other procedural stuff.
Obviously buying masks is discouraged because there is a shortage and hospitals have a much greater need for them than an uninfected person living in location as of yet untouched by the virus. Its about priorities.
As a side observation: most reporting seems rather binary, i.e. you either die or survive, period. What interests me the most, however, is how often survival means full recovery, especially now that the nervous system comes up. Are there any long term effects? Should one generally expect to come out of it worse, the same, or stronger? I'm much less afraid to die from this than to end up with chronic respiratory and/or neurological issues.
If it gets to the point of causing pneumonia, you may end up with permanent loss of lung tissue. If it spreads to the rest of the body, liver and kidney damage are also on the menu.
it is very likely the same circumstance.both those virus conserve the same cell fusion machinery, to the end of causing the same effect. The host may be variable and there is a basis for the range of morbidities observed. the central problem with lung damage involves disruptions to the RAS system that will lead to accumulations of extracellular fibres in the lung tissue
It has only been around for a few months so nobody knows. It is also too early to know about reinfection. My advice would be to avoid getting infected if you can but please be mindful that a lot of people won't have the privilege of avoiding it, and they do not need to be unduly stressed from the prospect.
There are patients that have been hospitalized in Wuhan for weeks or potentially months.
Will they ever recover? Will that compound the already-critical lack of medical infrastructure?
EDIT - Just to be clear, I'm not saying that people shouldn't take precautions or that it's not worth protecting vulnerable groups. I'm simply suggesting that perhaps there is news coverage about other things (remember the whole Hong Kong situation that we aren't hearing about suddenly?) that might still deserve some air time.
The media is profiting off this story big time. It's like when the plane went missing and a news station actually put some moron on the air who said there's technically a chance a black hole swallowed the plane. It's disgraceful, to be honest.
That said, it looks like the rate of fatalities is overblown significantly [0](0.2% in a healthy population (COMPARED WITH THE 3.4% NUMBER BEING SPOUTED ALL OVER THE PLACE). I've yet to see coverage that is remotely reputable about long-term health effects after recovery.
EDIT 2 - Case in point about premature statements being made.
> [1]“I think it is likely we’ll see a global pandemic,” said Marc Lipsitch, a professor of epidemiology at Harvard T.H. Chan School of Public Health. “If a pandemic happens, 40% to 70% of people world-wide are likely to be infected in the coming year. What proportion of those will be symptomatic, I can’t give a good number.”
followed by:
> [2]"Because I am now less certain of where the R0 will end up (and how it may vary geographically) I am going to revise downward the range of outcomes I consider plausible to 20%-60% of adults infected. This involves subjectivity about what range of R0 may turn out to be true."
It is getting annoying that people keeps comparing different numbers to make their points. If you are using 0.2% mortality rate in a healthy population, you have to compare it with the flu mortality's rate in a healthy population, which is still a magnitude lower. It's disgraceful, to be honest, to compare mortality rates on different population at all.
And I'm just gonna quote your link directly to make my point, I'm fairly upset at people calling it a bad flu at this point.
"While this correction does not change the assessment that COVID-19 exhibits severe pandemic potential in the absence of effective interventions, the shift in framing brought about by this three-fold revision from ‘possibly comparable to the 1957 flu but not 1918’ to ‘possibly comparable to 1918’ may meaningfully impact risk perception."
Its CFR is 3.4% according to WHO (actual number may be be higher than this because it is an early statistic and does not take into account patients that are still struggling and may eventually die).
So, in your opinion, the news coverage is totally justified and the lack of coverage for every other subject is okay? There's already 'effective interventions' being discussed openly from n95 masks to quarantines and travel restrictions.
Getting irritated at me for pointing out that the average person is not at severe risk of death, contrary to what the media is currently saying, seems a bit of an over-reaction.
That's not much consolation if someone close to you dies. I'm frustrated with the lack of empathy on display in discussions about this virus. People see 2% and then blow it off because "it probably won't happen to me". Those numbers represent real people with loved ones that will be 100% dead.
I appreciate the source. I'm still hopeful that the long-term effects of Covid-19 will turn out to be less dramatic than SARS but only time will tell I suppose.
Influenza has a CFR of 0.1%
COVID-19 has CFR of 2-3% (20-30x higher). Officially the CFR for COVID is ~3.3% but it is thought that is too high because there is thought to be many people who have it who are asymptomatic or have a mild reaction. FTR - 2% of 40% is 2.6 million.
The R0 is the highest driving factor for how many people will end up getting it the first year (aka R-Naught, is how many people on average an infected person spreads the infection to).
R0 for flu is 1.3. R0 for COVID is estimated to be 2.6, but I just read that the R0 is thought to be overestimated. and closer to 2.0. An R0 of 2.6 => closer to 70% of people. R0 of 2.0 => closer to 40% of people.
I think people forgets that if the ordinary flu would have caused this outbreak the counter measurements would probably be the same. But now it’s too late and too complex to stop it. Having two such viruses would probably very problematic and expensive. And which I believe many who compares this to the flu, forgets that we don’t know what this virus does and can cause. A person that had their lungs destroyed because, if true, the coronavirus still will have a miserable life than just dying. Assuming that the death rate is 1% there perhaps be 10% who will have major issues after an infection. That’s not dying but still bad enough.
I've seen very different estimates. I'm gonna go off on a limb and say that there's probably more misinformation out there than real information. People should remain calm, take [0]reasonable precautions, and make decisions based on the latest information from credible sources such as the [1]CDC - rather than the media.
> “I think it is likely we’ll see a global pandemic,” said Marc Lipsitch, a professor of epidemiology at Harvard T.H. Chan School of Public Health. “If a pandemic happens, 40% to 70% of people world-wide are likely to be infected in the coming year. What proportion of those will be symptomatic, I can’t give a good number.”
He has since revised his estimate down to 20-60%. Which is still a lot, of course, but I think reflects the uncertainty here. He's also been very clear about mitigating factors and the uncertainty on his twitter account.
So, basically, you proved my point that everyone is so damn eager to talk about this that they'll make claims without sufficient evidence and scare people into distress.
As someone who is in Hong Kong, there's a good reason you don't hear about the Hong Kong situation. A lot of people in Hong Kong are in pseudo self quarantine, working remotely, going to school remotely, avoiding any areas with a lot of people, wearing masks all the time,...
This doesn't lead to protesting easily. It doesn't stop the fact that pretty much everyone here is unhappy with Carrie Lam.
And to be fair, the relatively slow growth of the number of cases we have in Hong Kong might be due to all the precautions people take (although I haven't found any information on the total number of people tested in Hong Kong so it might be because not enough people are tested)
I would like to see more details about those affected, age, immuno compromised or not, asthma or not. Its hard to really draw any comparison to flu or anything else as things stand right now.
I have mild persistent asthma, for example, which for me means if I take a daily (low) dose of an inhaled corticosteroid, I can generally go about my business like a normal person and almost never need to use my rescue inhaler.
I've only seen stats for COVID-19 fatalities for people with "respiratory conditions." Which could be anything from mild asthma on up to stuff like emphysema and cystic fibrosis.
If you're below 50 your chances of dying after contracting the virus are similar to that of being in a car accident if you got in a car over the course of one year (I think a car accident is higher). https://www.worldometers.info/coronavirus/coronavirus-age-se...
I'm not sure exactly how they evaluate risk, but they probably estimate the error based on populations where very few people are studied (probably most people below 50), so it's likely if you're below 50 the chances are actually lower, I'm not sure.
Risk factors for immune disorders and car accidents are probably similar if I were to conjecture (just in: sick people tend to die), so most people on this subreddit will just get the fever. 15% of people don't even present with a fever, so it seems like the immune system can typically fight it off.
Whether you believe this or not comes down to whether you believe references 32-34 from the paper. I haven't read the stuff about transgenic expression of human ace2 in mice, but it would sound a lot more like it was aberrantly expressed, so I'm not counting that. "More evidence needed" is the correct interpretation here, I believe.
There's other literature out there saying ACE2 is ubiquitously expressed (including brain) - so that means one of two things: People saying it's expressed everywhere are wrong, or SARS-COV-2 requires more than ACE2 for infection. There are papers saying that transfecting cell lines with ACE2 doesn't always render the cells susceptible, so it's probably a good idea to consider the requirement for a co-receptor.
Like anything, the true answer probably lies in between all these possibilities.
This is almost a week old, I haven't read about it anywhere else. I have read and heard plenty of interviews with scientists involved in this in the past few days and noone has mentioned anything in that direction.
Anyone has any link to secondary sources where other scientists try to put this in perspective?
> According to the complaints of a survivor, the medical graduate student (24 years old) from Wuhan University, she must stay awake and breathe consciously and actively during the intensive care. She said that if she fell asleep, she might die because she had lost her natural breath
Reminiscent of the Polio outbreak/iron lung era. A survivor described the sound of clicking tounges in iron lung rooms after the electricity had failed and a few nurses needed to rotate between devices, manually pumping air. Tounge clicking because no one had the ability to exhale air and produce vocal sounds.
I've only read the abstract, and it seems to clearly say that the virus can get to the brain via the lungs. So I have no idea what people ITT are on about regarding purposeful infection or masks for prevention. Regardless, this abstract also does not explain the mildness of the disease except for the immunocompromised and elderly, which to me renders the link between how you get the infection and fatality a bit suspicious.
If you read more than the abstract, it explains that animals that are infected nasally have much higher rates of brain infection than the fecal-oral route of infection.
Edit: changed "oral/fecal" to "fecal-oral," thanks calmworm. Also removed a period.
Not a biologist, but reading the paper, the chain of reasoning appears to be summarized in this section:
> Taken together, the neuroinvasive propensity has been demonstrated as a common feature of CoVs. In light of the high similarity between SARS-CoV and SARS-CoV2, it is quite likely that SARS-CoV-2 also possesses a similar potential. Based on an epidemiological survey on COVID-19, the median time from the first symptom to dyspnea was 5.0 days, to hospital admission was 7.0 days, and to the intensive care was 8.0 days 15. Therefore, the latency period is enough for the virus to
enter and destroy the medullary neurons. As a matter of fact, it has been reported that some patients infected with SARS-CoV-2 did show neurologic signs such as headache (about 8%), nausea and vomiting (1%).
There's also this rather disquieting anecdote used as evidence of a link to the nervous system:
> According to the complaints of a survivor, the medical graduate student (24 years old) from Wuhan University, she
must stay awake and breathe consciously and actively during the intensive care. She said that if she fell asleep, she might die because she had lost her natural breath.
Supposing that this neurological link is real,
> the precaution with masks will absolutely be the most effective measure to protect against the possible entry of the virus into the CNS. It may also be expected that the symptoms of the patients infected via facal-oral [sic?] or conjunctival route will be lighter than those infected intranasally. The possible neuroinvasion of SARS-CoV-2 may also partially explain why some patients developed respiratory failure, while others not. It is very possible that most of the persons in Wuhan, who were the first exposed to this previously unknown virus, did not have any protective measure, so that the critical patients is much more in Wuhan than in other cities in China.
So let me ask a dumb question for someone with actual biomedical knowledge. Are they saying that infection of the CNS is somehow easier through the nose, in which case high-quality face masks actually do matter?
I'm also confused by this sentence in the introduction, which appears to contradict the hypothesis that the upper respiratory tract is a high-impact area?
> However, different from SARS-CoV, SARS-CoV-2-infected patients rarely showed prominent upper respiratory tract signs
and symptoms, indicating that the target cells of SARS-CoV-2 may be located in the lower airway.
I will note that, unlike some other papers on this topic, this one has been peer-reviewed in what seems to be a legitimate medical journal (Journal of Medical Virology), so there should be some genuine substance here.
1. I am not familiar with coronavirus biology, however, as to the general question about nasal -> brain routes if infection: yes this is a risk if the virus is able to infect the olfactory nerves and travel retrograde through the cribriform plate into the olfactory bulb. It is a little peculiar that it would lead to medullary viral replication, as the medulla is a few steps back and distal from the olfactory bulb. Other infectious agents can travel into the CNS via the cribriform plate, most terrifying is naegleria fowleri but other terrible fungal infections like mucor and rhizopus can do it as well. They don’t tend to grow in neurons but rather eat through the tissues.
2. Upper versus lower: when people have a URI the upper airways meaning the nasopharyngeal, oropharyngeal, and trachea are predominantly affected. The typical symptoms are runny nose, nasal congestion, sore throat. However, SARS/COVID tends to cause a lower respiratory syndrome affecting the small airways deep in the lungs, namely the alveoli and small bronchioles. It is entirely consistent to hypothesize that infection through the upper airway mucosa is “worse” but the target cells that primarily cause disease are in the lower airway.
> So let me ask a dumb question for someone with actual biomedical knowledge. Are they saying that infection of the CNS is somehow easier through the nose, in which case high-quality face masks actually do matter?
The olfactory receptors (nerves that smell) are among the most exposed nerves of the body, and IIRC they are single cells stretching from the mucus membrane in your nose all the way to the brain. And because smell is such an evolutionary ancient function, the relevant brain region is really close to the centre of the brain (and brainstem).
So it's really just two hops from the outside world to the command post of your autonomous nervous system (i. e. breathing)
> There's also this rather disquieting anecdote used as evidence of a link to the nervous system:
> According to the complaints of a survivor, the medical graduate student (24 years old) from Wuhan University, she must stay awake and breathe consciously and actively during the intensive care. She said that if she fell asleep, she might die because she had lost her natural breath.
Would that explain people collapsing suddenly on the streets as seen in Wuhan and Iran?
No, I think that'd be very unlikely because it'd be a late symptom after substantial damage has been done. Compared to the frequency of syncopal episodes I'd expect in people sick with any other cold or flu, I think it's overwhelmingly more likely to be from other causes.
And if it actually were causing neurological damage, I'd expect still more causes like seizures and the like.
> Is this how people typically write a paper to Medical Virology?
I wont assume that (I am software engg.)
I see where you are coming from. Here is my perspective, think of this like a outage of your service. No one has exact answers so team starts to dive in and starts sharing what they find.
These findings mostly prune the "solution space" of the problem.
> Is this how people typically write a paper to Medical Virology?
As with the other person, I'm not in the field so I can't actually answer.
My prior, though, would be that papers that come in the early period of a response to a global widespread disease are not representative of the typical status quo in the field.
Recently I started listening twiv.tv podcast and that's how they talk. For instance, they said there are many videos in social media of people dropping unconscious to the floor, but the virologists said not to trust those videos because "it's social media". I stopped listening to their podcast. These people don't reason unless they are shown a peer reviewed paper saying people drop unconscious. I mean, how likely is it that those videos are being faked?
>Provocation studies on EMF have yielded different results, ranging from where people with EHS cannot discriminate between an active RF signal and placebo, to objectively observed changes following exposure in reactions of the pupil, changes in heart rhythm, damage to erythrocytes, and disturbed glucose metabolism in the brain.
The paper you linked admits that there are studies that show it's the same as a placebo. Just because most people aren't qualified to realize that the studies in the first half of the sentence might be more reliable than the studies in the second half doesn't mean the paper shouldn't be published.
So? You can say exactly the same things about ESP or dowsing. Run enough studies, even properly-conducted ones, and some of them will yield the results you're hoping for. At that point, all you have to do is either ignore the others altogether, or leverage them to argue in favor of "teaching the controversy," as is done in this particular paper.
This strategy is meaningless in terms of scientific value, but it certainly sounds authentic enough to non-specialists.
> It may also be expected that the symptoms of the patients infected via facal-oral or conjunctival route will be lighter than those infected intranasally.
That seems like the hypothesis they suggest. Interesting implications.
Your nasal passages include structures called "conchae" which, among other purposes, secrete mucus to capture small and potentially disease-carrying particles from incoming air. [1] It's not a perfect defense, of course, but better to have it than not - and when you breathe through your mouth, you don't get the benefit.
If it did turn out this virus is neuroinvasive and that is what causes acute respiratory problems, how would this be prevented/mitigated/treated, theoretically?
> Considering the potential neuroinvasion of SARS-CoV-2, antiviral therapy
should be carried out as early as possible to block its entry into the CNS. Airway inhalation of antiviral agents will be the first choice at the early stage of infection,
which will inhibit the replication SARS-CoV-2 in the respiratory tracts and lung and
prevent from its subsequent neuroinvasion. It is also urgent to find effective antiviral
drugs that can cross the blood-brain barrier. Moreover, corticosteroids, which are used
frequently for severe patients, may have no treatment effect, but rather accelerate the
replication of the virus within the neurons.
Yes, but it suggests that it could be important to distinguish whether the cause of their decline and hypoxia is CNS respiratory depression or issues with lung function before making that call.
The full text mentions masks being particularly effective and inhaled antiviral meds that could slow the spread of the virus in airways. It also talks about the need for antiviral agents capable of crossing the brain-blood barrier. See the last 3 paragraphs of the full text.
As a sort of "vaccine", would it make sense to have people intentionally infected orally so they build up antibodies before it has a chance to spread to their brain?
Great. I work in an E.R. and my neurological system is already being ravaged by M.S. I'm not sure that I would not just walk off of the job if we are inundated with COVID-19 patients.
Question what effect is vaping having on the spread? Walking in a city in the UK I see people leave large plumes of vaper which seems to me be an excellent transport system.
There have been some theories (that has not been tested at all) that hot and humid climates might be less susceptible to the virus due to the virus not surviving in the air as long. Not sure if this can be applied to small vapor clouds though.
It is interesting how absolutely passionate some people are about masks. There is a pretty heady contingent here that seems to be of the "I DID MY PART" sort (by mindlessly pushing an absurd anti-science anti-mask angle -- I was one of the silly minority countering it a few days ago, to very little effect).
"If you wear a mask your testicles will shrink and everyone will hate you!"
But the more important question: Is it time to stop trimming nose hairs?
Airborne viral particle protection: N95 masks may only be effective used with eye protection. Surgical masks may not help at all.
Looked for interventional studies testing whether face masks and eye protection work in humans to protect against airborne viral particles. A critical issue with many such studies is that medical staff only use masks and/or eye protection at work, opening them to being infected outside of work.
Found a small study [1] getting around this problem by exposing subjects (n = 28, avg age 30.5 years) to monodispersed live attenuated influenza vaccine particles by placing them in front of a vibrating-orifice aerosol generator for 20 minutes, subsequently testing for infection using RT-PCR and culture in nasal washes.
Surgical mask + eye protection: 5 out of 5 infected.
N95 mask only: 3 out of 5 infected.
N95 mask + eye protection: 1 out of 5 infected.
1. Bischoff WE, Reid T, Russell GB, Peters TR. Transocular entry of seasonal influenza-attenuated virus aerosols and the efficacy of n95 respirators, surgical masks, and eye protection in humans. J Infect Dis. 2011;204(2):193–199.
I was actually wondering about this because both the Spanish Flu and the 2009 H1N1 pandemics left life-long brain damage for some survivors in the form of narcolepsy with cataplexy. The vaccine for H1N1 caused it in a very small amount of patients as well. After the Spanish Flu they called it "encephalitis lethargica". It appears that it damages the hypothalamus.
Who wants to help make a design file for 3d printed nose plugs? If blocking the intranasal path is effective in preventing the CNS infection, as this paper suggests, nose plugs should be effective here.
keep in mind this is a preliminary, the grammar used in this paper needs to be revised so as to avoid as much as possible, people coming to errant conclusions after misinterpreting poorly written phrases.
so that means that while reading this paper one should not skim but should take the effort to interpret this paper.
there is an absence of references in the abstract, this makes it hard to examine the basis for statements in abstract
In your own source it is said unproven with detailed explanation:
>If we strip the above-displayed videos of their captions, we can take a look purely at what the videos show. In one case, it looks like a person was the victim of a traffic accident. In another, it appears that a man suffered a head injury. But since these videos appeared online during heightened hysteria about an outbreak of an illness, it’s easy to see how a passerby may have made the assumption that these incidents were connected to the coronavirus.
Folks, if you see someone collapse on the street and they're wearing a mask. TAKE THE MASK OFF OF THEM. They're not getting enough oxygen. It is taxing to breath through an N95 mask. Source: I passed out when I put on a surgical mask while my wife was getting an epidural. Not from seeing the needle because I didn't even see the needle, and I don't get squeamish anyway. I have low blood oxygen and it was too hard to breath through the mask.
> If the neuroinvasion of SARS-CoV-2 does take a part in the development of respiratory failure in COVID-19 patients, the precaution with masks will absolutely be the most effective measure to protect against the possible entry of the virus into the CNS. It may also be expected that the symptoms of the patients infected via facal-oral or conjunctival route will be lighter than those infected intranasally. The possible neuroinvasion of SARS-CoV-2 may also partially explain why some patients developed respiratory failure, while others not. It is very possible that most of the persons in Wuhan, who were the first exposed to this previously unknown virus, did not have any protective measure, so that the critical patients is much more in Wuhan than in other cities in China.
This is a good example of why writing off COVID-19 as no more dangerous than the flu is itself so dangerous.
I should also point out that most people in the US face similar conditions to those in Wuhan. The extent of infection is not known, and therefore protective measures are not in place. We have been actively discouraged from "buying masks" and told that they are ineffective.