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I really see the strong, immediate pushback against this idea as mainly an attempt to calm the lay audience. Ebola has been airborne in other species before, an

by themgt 12y ago

I really see the strong, immediate pushback against this idea as mainly an attempt to calm the lay audience. Ebola has been airborne in other species before, and it's very nearly airborne in humans - this is certainly not a virus like HIV where even unprotected sexual intercourse has a low infection rate - we've got a huge number of infected doctors and healthcare workers, and there are calls for this to be treated like SARS: "Infection control concerning EVD is not working, especially when more than 240 [now 300] healthcare personnel have been infected, and more than 120 workers have died. Guidelines used to control SARS in 2003 should be used, not "contact and droplet protection of 1-2 meters," as is still recommended by WHO. Personal protective equipment (PPE) for contact and airborne infections should be used because of a) respiratory symptoms, b) a big distance -- up to 9 meters -- for droplets when coughing and sneezing (Bourouiba et al. J Fluid Mechanics 2014;745:537-563.), c) re-aerolization from the environment, bed clothes etc., d) long survival of the virus outside the body, and e) high lethality. Healthcare workers (HCW) and helpers should be protected with PPE as they were during the SARS epidemic." http://www.promedmail.org/direct.php?id=20140914.2773490 http://www.promedmail.org/direct.php?id=20140914.2773490 The real question is more like, will Ebola mutate to be more airborne than it already is?

TeMPOraL 12y ago
> I really see the strong, immediate pushback against this idea as mainly an attempt to calm the lay audience. Little off-topic, but reminds me of something I read once - if the government tells you to panic, it's probably nothing important and will blow over soon. When they tell you to keep calm and carry on, then it's probably the time to be really worried.
- gugachiu 12y ago
  It's an interesting statement but if taken at its face value, we should have all been a lot more worried about December 21st, 2012 and the Mayan Calendar ending.
  - cordite 12y ago
    Maybe the Y2K hype softened most of those who would react.
    - cstross 12y ago
      Y2K wasn't hype: if we hadn't done the work, the outcome would have been moderately gruesome. (Not world-ending-apocalyptic gruesome, but not-getting-paid-for-a-month-and-the-stock-market-crashed gruesome.) Indeed, it was largely due to Y2K resilience preparations that the Federal Reserve managed to keep running on 9/11: http://www.dailykos.com/story/2014/09/10/1328813/-The-Astonishing-Story-of-the-Federal-Reserve-on-9-11 http://www.dailykos.com/story/2014/09/10/1328813/-The-Astoni... Upshot: it might look like hype, but sometimes it's actually the symptom of a bullet dodged just in time. (Which is why I hope that this time next year, when we look back at the Ebola outbreak, there will be plenty of folks saying "nope, it was overhyped fear-mongering".)
- rsync 12y ago
  With that in mind, I remember being particularly interested in the way, during the gore/bush election recounts and court battles, the "rule of law" turn of phrase was suddenly injected into common (tv news) discourse and repeated ad nauseam. I'd never heard that term being used in low-brow discourse before, and suddenly we heard it from every news source, every five minutes.
- wlievens 12y ago
  When has a modern government told its citizens to panic?
  - marcosdumay 12y ago
    Terrorists!
DennisP 12y ago
I didn't actually find the article that reassuring. It boiled down to "it's unlikely to evolve true airborne transmission because it doesn't need to bother, it's plenty infectious through another route already."
- undata 12y ago
  Evolution doesn't ask itself whether it needs to "bother".
  - hencq 12y ago
    It doesn't ask itself that, but an airborne mutation wouldn't have a meaningful advantage, since the current virus is highly effective in spreading already.
  - baq 12y ago
    exactly what the article was talking about.
  - Tloewald 12y ago
    The article's point is that it needs several mutations to become airborne and that those mutations have a cost; so unless the benefit of becoming airborne outweighs the cost, it won't happen. Bear in mind that the traditional method of dealing with Ebola was simply to shut down travel in/out of affected settlements until the disease ran its course. This isn't working as well this time for a variety of reasons (I'll guess increased urbanization, better transportation, and problems with public information -- e.g. distrust of governments telling people to do sensible things). What's probably far more likely is that a less lethal mutation will displace it. A disease that kills and kills quickly is maladaptive -- that's why the Ebola reservoir is believed to be bats which can catch it but not suffer ill effects.
    - andy_ppp 12y ago
      Cost simply isn't how it works, the mutations are completely random. It has no direction other than chance as to if it becomes airborne. People can talk about it but a strain this virulent going airborne would be a disaster.
JunkDNA 12y ago
The article addresses the so-called airborne nature of Ebola in other species and calls into question whether or not it was truly airborne in those instances. Furthermore, "very nearly airborne" is not a fair characterization. Bodily fluids transmit the disease, and Ebola's particular ability to make people spew lots of virus all over the place from every available orifice seems to be the primary way to spread. The odds of getting droplets in the eye, on a small cut on your skin, etc... as a healthcare worker are very high if someone is spraying virus-laden blood all over the place. But this is not what we're talking about with a truly airborne virus. In the case of an airborne virus like influenza, you have infection via the upper respiratory tract from viral particles that survive for extended amounts of time in aerosols suspended in the air. There is no evidence Ebola can or does spread in this manner. Obviously nobody can predict the future, but viruses that infect via the airway are highly evolved to do so. The article touches on it a bit, but doesn't get into the real specifics. I'm going from memory here, but I recall that in things like the common cold and influenza, the viral proteins have specific humidity, pH, and temperature requirements in order to dock with receptors in just the right part of the airway in order to maximize infection. You don't get that without significant evolutionary pressure which as far as I can tell is totally absent in the current environment. The virus is easily spreading via direct contact with body fluids, so even if it develops an ability to spread by air, this offers little advantage over the plain old bodily fluid route.
thathonkey 12y ago
That's all well and good but a slew of actual virologists disagree with this, citing examples such as no viruses affecting humans ever changing from being spreadable via bodily fluid/direct contact to becoming aerosol. This includes all viruses that have ever been known to affect human beings. So, yes, while it is theoretically possible, it is extremely unlikely and really not worth discussing because no good can come from it.
- joeguilmette 12y ago
  As the parent comment states, the question isn't will Ebola completely change it's infection vector to become airborne. Someone who has Ebola today can cough blood. If you become infected from someone coughing blood on you, does it matter that the infection came from the blood on their breath or from virus on their breath? It seems that virologists are answering the wrong question and getting caught up on semantics, perhaps to prevent more hand wringing and panic. Edit: removed statements about Reston, as they seem to have been remembered incorrectly from Hot Zone, the book about the primate-only Ebola outbreak in Virginia in the 90s.
  - thathonkey 12y ago
    You're confusing "spreads via an exchange of body fluids" (getting sneezed or coughed on by an infected individual would be included in this category) with "can survive and therefore spread via the air without any direct contact with bodily fluids" (walking outside of your house and breathing). You can't even call that a "semantic" distinction without coming off as really dishonest considering it's a totally different infection vector. Anyway, I'm just arguing the points I've heard made by ACTUAL VIROLOGISTS. Read: PhDs who have been studying this exact behavior in viruses for many years. They've all said the same thing: theoretically possible, extremely unlikely.
    - joeguilmette 12y ago
      I think we're actually in agreement. To be fair tho, influenza is airborne, but you're not going to contract it by going outside and breathing, unless you're being breathed on by someone with the flu, or shaking their hand. My point is that being breathed on, or even in close proximity to someone with Ebola is likely to result in you contracting the disease without actually touching them, as it is with influenza. So, does it matter if the virus isn't 'airborne' in the strict medical sense if it is just as contractable as one that is from things like coughing? It's a question, and not a rhetorical one.
joe_the_user 12y ago
The link you quote is speculating on the needed guidelines based on "existing guidelines" failing - yet with these primitive conditions it's hard to see the infection of health care worker as being caused by these guidelines. The level of protection being used by health care workers in the affected area seems to be determined by the fact that these are essentially the poorest nations in the world, with health care systems that barely functioned before the outbreak. Reports indicate most Ebola clinics lack running water. Hopefully reports of donated masks and gloves indicate they will enough supplies soon. But until recently, many also lacked even rubber gloves. I'm sure a good supply of PPEs would appreciated anyone could offer them, however.

by themgt 12y ago

TeMPOraL 12y ago

> I really see the strong, immediate pushback against this idea as mainly an attempt to calm the lay audience. Little off-topic, but reminds me of something I read once - if the government tells you to panic, it's probably nothing important and will blow over soon. When they tell you to keep calm and carry on, then it's probably the time to be really worried.

gugachiu 12y ago
It's an interesting statement but if taken at its face value, we should have all been a lot more worried about December 21st, 2012 and the Mayan Calendar ending.
- cordite 12y ago
  Maybe the Y2K hype softened most of those who would react.
  - cstross 12y ago
    Y2K wasn't hype: if we hadn't done the work, the outcome would have been moderately gruesome. (Not world-ending-apocalyptic gruesome, but not-getting-paid-for-a-month-and-the-stock-market-crashed gruesome.) Indeed, it was largely due to Y2K resilience preparations that the Federal Reserve managed to keep running on 9/11: http://www.dailykos.com/story/2014/09/10/1328813/-The-Astonishing-Story-of-the-Federal-Reserve-on-9-11 http://www.dailykos.com/story/2014/09/10/1328813/-The-Astoni... Upshot: it might look like hype, but sometimes it's actually the symptom of a bullet dodged just in time. (Which is why I hope that this time next year, when we look back at the Ebola outbreak, there will be plenty of folks saying "nope, it was overhyped fear-mongering".)
rsync 12y ago
With that in mind, I remember being particularly interested in the way, during the gore/bush election recounts and court battles, the "rule of law" turn of phrase was suddenly injected into common (tv news) discourse and repeated ad nauseam. I'd never heard that term being used in low-brow discourse before, and suddenly we heard it from every news source, every five minutes.
wlievens 12y ago
When has a modern government told its citizens to panic?
- marcosdumay 12y ago
  Terrorists!

DennisP 12y ago

I didn't actually find the article that reassuring. It boiled down to "it's unlikely to evolve true airborne transmission because it doesn't need to bother, it's plenty infectious through another route already."

undata 12y ago
Evolution doesn't ask itself whether it needs to "bother".
- hencq 12y ago
  It doesn't ask itself that, but an airborne mutation wouldn't have a meaningful advantage, since the current virus is highly effective in spreading already.
- baq 12y ago
  exactly what the article was talking about.
- Tloewald 12y ago
  The article's point is that it needs several mutations to become airborne and that those mutations have a cost; so unless the benefit of becoming airborne outweighs the cost, it won't happen. Bear in mind that the traditional method of dealing with Ebola was simply to shut down travel in/out of affected settlements until the disease ran its course. This isn't working as well this time for a variety of reasons (I'll guess increased urbanization, better transportation, and problems with public information -- e.g. distrust of governments telling people to do sensible things). What's probably far more likely is that a less lethal mutation will displace it. A disease that kills and kills quickly is maladaptive -- that's why the Ebola reservoir is believed to be bats which can catch it but not suffer ill effects.
  - andy_ppp 12y ago
    Cost simply isn't how it works, the mutations are completely random. It has no direction other than chance as to if it becomes airborne. People can talk about it but a strain this virulent going airborne would be a disaster.

JunkDNA 12y ago

The article addresses the so-called airborne nature of Ebola in other species and calls into question whether or not it was truly airborne in those instances. Furthermore, "very nearly airborne" is not a fair characterization. Bodily fluids transmit the disease, and Ebola's particular ability to make people spew lots of virus all over the place from every available orifice seems to be the primary way to spread. The odds of getting droplets in the eye, on a small cut on your skin, etc... as a healthcare worker are very high if someone is spraying virus-laden blood all over the place. But this is not what we're talking about with a truly airborne virus. In the case of an airborne virus like influenza, you have infection via the upper respiratory tract from viral particles that survive for extended amounts of time in aerosols suspended in the air. There is no evidence Ebola can or does spread in this manner. Obviously nobody can predict the future, but viruses that infect via the airway are highly evolved to do so. The article touches on it a bit, but doesn't get into the real specifics. I'm going from memory here, but I recall that in things like the common cold and influenza, the viral proteins have specific humidity, pH, and temperature requirements in order to dock with receptors in just the right part of the airway in order to maximize infection. You don't get that without significant evolutionary pressure which as far as I can tell is totally absent in the current environment. The virus is easily spreading via direct contact with body fluids, so even if it develops an ability to spread by air, this offers little advantage over the plain old bodily fluid route.

thathonkey 12y ago

That's all well and good but a slew of actual virologists disagree with this, citing examples such as no viruses affecting humans ever changing from being spreadable via bodily fluid/direct contact to becoming aerosol. This includes all viruses that have ever been known to affect human beings. So, yes, while it is theoretically possible, it is extremely unlikely and really not worth discussing because no good can come from it.

joeguilmette 12y ago
As the parent comment states, the question isn't will Ebola completely change it's infection vector to become airborne. Someone who has Ebola today can cough blood. If you become infected from someone coughing blood on you, does it matter that the infection came from the blood on their breath or from virus on their breath? It seems that virologists are answering the wrong question and getting caught up on semantics, perhaps to prevent more hand wringing and panic. Edit: removed statements about Reston, as they seem to have been remembered incorrectly from Hot Zone, the book about the primate-only Ebola outbreak in Virginia in the 90s.
- thathonkey 12y ago
  You're confusing "spreads via an exchange of body fluids" (getting sneezed or coughed on by an infected individual would be included in this category) with "can survive and therefore spread via the air without any direct contact with bodily fluids" (walking outside of your house and breathing). You can't even call that a "semantic" distinction without coming off as really dishonest considering it's a totally different infection vector. Anyway, I'm just arguing the points I've heard made by ACTUAL VIROLOGISTS. Read: PhDs who have been studying this exact behavior in viruses for many years. They've all said the same thing: theoretically possible, extremely unlikely.
  - joeguilmette 12y ago
    I think we're actually in agreement. To be fair tho, influenza is airborne, but you're not going to contract it by going outside and breathing, unless you're being breathed on by someone with the flu, or shaking their hand. My point is that being breathed on, or even in close proximity to someone with Ebola is likely to result in you contracting the disease without actually touching them, as it is with influenza. So, does it matter if the virus isn't 'airborne' in the strict medical sense if it is just as contractable as one that is from things like coughing? It's a question, and not a rhetorical one.

joe_the_user 12y ago

The link you quote is speculating on the needed guidelines based on "existing guidelines" failing - yet with these primitive conditions it's hard to see the infection of health care worker as being caused by these guidelines. The level of protection being used by health care workers in the affected area seems to be determined by the fact that these are essentially the poorest nations in the world, with health care systems that barely functioned before the outbreak. Reports indicate most Ebola clinics lack running water. Hopefully reports of donated masks and gloves indicate they will enough supplies soon. But until recently, many also lacked even rubber gloves. I'm sure a good supply of PPEs would appreciated anyone could offer them, however.