That seems strange. Both the antibody test I had at a county run testing site and the antibody tests my girlfriends' employer purchased take less than 20 mins.
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Cont: The One Covid-19 Science and Medicine Thread Part 2
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Rolfe
Adult human female
Oh for goodness sake this is not an airborne virus. Correct terminology is important. If it was airborne everyone would have to stay inside with the windows closed. Ordinary cloth and surgical masks would do very little to prevent spread. You'd be in danger of catching it from me if I was infected and you were a couple of miles downwind.
Measles is airborne. Foot and mouth disease, famously, is airborne. So are a bunch of other things including many spore-forming bacteria. SARS-CoV-2, thankfully, is not.
The people pushing the canard that this is airborne mainly want to terrify you into believing the virus can't be contained and lockdowns won't help and we should all just give up, go to work and accept that herd immunity is the only endpoint. They don't want you to wear a mask because they point out how very much smaller the virus itself is than the pores even of a proper mask never mind a cloth mask. It's pernicious.
The virus has three modes of transmission.
What happened to the Skagit Valley Chorale on 10th March couldn't have happened in any other way than by aerosol transfer. There are at least two other choir outbreaks in that category. Nevertheless I saw an article in the Guardian by some idiot physicist who claimed that singing was perfectly safe because it didn't expel Flügge droplets far enough to be a risk. Bad advice. I've been in correspondence with various choirmasters and musical directors pushing this point pretty much since our choir practice scheduled for 15th March was pulled on the advice of the village doctor. The choral singing community understands and is sorrowfully making plans not to re-convene until the virus is properly suppressed.
Yes there needs to be greater awareness of aerosol spread. Yes people need more guidance about talking quietly and not shouting or yelling or talking loudly and animatedly and for God's sake no singing - indoors. Aerosols can only build up in a way that allows an infective dose to be transferred in an enclosed space. Out of doors and they're simply wafted away in the breeze or diluted in the infinite airspace all around. We're thinking of getting together for some al fresco choir practice over the summer.
Aerosol spread is still droplet spread. The virus is still contained in a moisture droplet, just one that's small enough to be suspended. Therefore it's still inhibited to a pretty good extent by masks. It also means that out of doors is safe so long as you stay far enough away to avoid Flügge droplets.
Airborne transmission is something else again and thank goodness it's not involved in this one. It is not going to blow in the window and get you. It's not going to get you while you're out on a country walk in the fresh air. That's what airborne viruses do. People need to stop saying that it is, because it's scaremongering, it's giving ammunition to the herd immunity pedlars (and the "masks are useless" lobby) and it's wrong.
Here's a good article that explains all this and more. The risks - know them - avoid them
Measles is airborne. Foot and mouth disease, famously, is airborne. So are a bunch of other things including many spore-forming bacteria. SARS-CoV-2, thankfully, is not.
The people pushing the canard that this is airborne mainly want to terrify you into believing the virus can't be contained and lockdowns won't help and we should all just give up, go to work and accept that herd immunity is the only endpoint. They don't want you to wear a mask because they point out how very much smaller the virus itself is than the pores even of a proper mask never mind a cloth mask. It's pernicious.
The virus has three modes of transmission.
- Large (Flügge) droplets that are acted on by gravity and which can be avoided by staying 2 metres back
- Fomite (touch) transmission where an inanimate object like a door handle transfers virus to another host (fomites become contaminated either by touch or by having droplets land on them)
- Aerosol droplets that are small enough to remain suspended in the air for some time, probably around half an hour. These contain significantly fewer viral particles than Flügge droplets and so more need to be inhaled in order to acquire an infectious dose, on the other hand they're easier to inhale right into your lungs
What happened to the Skagit Valley Chorale on 10th March couldn't have happened in any other way than by aerosol transfer. There are at least two other choir outbreaks in that category. Nevertheless I saw an article in the Guardian by some idiot physicist who claimed that singing was perfectly safe because it didn't expel Flügge droplets far enough to be a risk. Bad advice. I've been in correspondence with various choirmasters and musical directors pushing this point pretty much since our choir practice scheduled for 15th March was pulled on the advice of the village doctor. The choral singing community understands and is sorrowfully making plans not to re-convene until the virus is properly suppressed.
Yes there needs to be greater awareness of aerosol spread. Yes people need more guidance about talking quietly and not shouting or yelling or talking loudly and animatedly and for God's sake no singing - indoors. Aerosols can only build up in a way that allows an infective dose to be transferred in an enclosed space. Out of doors and they're simply wafted away in the breeze or diluted in the infinite airspace all around. We're thinking of getting together for some al fresco choir practice over the summer.
Aerosol spread is still droplet spread. The virus is still contained in a moisture droplet, just one that's small enough to be suspended. Therefore it's still inhibited to a pretty good extent by masks. It also means that out of doors is safe so long as you stay far enough away to avoid Flügge droplets.
Airborne transmission is something else again and thank goodness it's not involved in this one. It is not going to blow in the window and get you. It's not going to get you while you're out on a country walk in the fresh air. That's what airborne viruses do. People need to stop saying that it is, because it's scaremongering, it's giving ammunition to the herd immunity pedlars (and the "masks are useless" lobby) and it's wrong.
Here's a good article that explains all this and more. The risks - know them - avoid them
Skeptic Ginger
Nasty Woman
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Calm down. I know the ******* difference. And the surgical masks do very little to protect the wearer. No one said it traveled miles. Even measles doesn't spread miles downwind.
May 6th Preprint: Re-thinking the Potential for Airborne Transmission of SARS-CoV-2 (I posted this link earlier.)
July 5th: NYT: Scientists Prepare Letter to WHO Insisting COVID-19 Is Airborne
They did publish the letter.
It's not foodborne either but there is evidence if your food is directly contaminated that can transfer the virus to your mouth the same way you can contaminate your mouth with your hand. (I posted that study earlier.)
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Blue Mountain
Resident Skeptical Hobbit
Thanks for the elaboration. If that's indeed the case, is a vaccine necessary? Or can we simply rely on contact tracing and isolation to knock it out?
Thinking on my last question, it might be possible to stamp it out with contract tracing and isolation—if humans weren't so darned stupid. So we really need to develop a vaccine as well.
marting
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Masks are mostly to protect others from the infected and don't really do much filtering inhalations after exhaled small droplets evaporate and get even smaller. This work suggests nose plugs might be somewhat effective. Alternately, become a mouth breather.
https://www.cell.com/cell/pdf/S0092-8674(20)30675-9.pdf
https://www.cell.com/cell/pdf/S0092-8674(20)30675-9.pdf
gypsyjackson
Master Poster
When I was working on bird flu about 15 years ago, the Deputy Chief Vet told me that he suspected the adjuvant in the vaccines available then (mostly mineral oil in those) could actually have a close to equal effect to the vaccine itself - that injecting the birds with just paraffin could stir up their immune system enough to be as effective as the expensive and not field-tested jabs. I’m not sure if he was joking.
Rolfe
Adult human female
Yes there are people who should know better using the word "airborne". That doesn't make it right. It's scaremongering and it's playing into the hands of people who want to abandon lockdowns and even social distancing and believe the virus can't be stopped.
ETA: https://www.bbc.co.uk/news/world-53329946
This is nuts. Aerosol spread has been known about for months. I was writing emails about it to friends in musical circles in April. Now the WHO is saying it "can't be ruled out"!? I mean where have they been? And they're calling it airborne, which is disastrously wrong.
At least the professor who is quoted in the article gets the terminology right, but this shouldn't be allowed to continue. Aerosol and airborne are two completely different modes of transmission and they must be distinguished.
And if people are still saying things like "if this is confirmed" and "we may need to change the guidelines" at this stage, where have they been for the past four months? People have been writing about this for months and if anyone had any doubts at all then Skegit Valley (10th March) should have knocked them on the head.
ETA: https://www.bbc.co.uk/news/world-53329946
This is nuts. Aerosol spread has been known about for months. I was writing emails about it to friends in musical circles in April. Now the WHO is saying it "can't be ruled out"!? I mean where have they been? And they're calling it airborne, which is disastrously wrong.
At least the professor who is quoted in the article gets the terminology right, but this shouldn't be allowed to continue. Aerosol and airborne are two completely different modes of transmission and they must be distinguished.
And if people are still saying things like "if this is confirmed" and "we may need to change the guidelines" at this stage, where have they been for the past four months? People have been writing about this for months and if anyone had any doubts at all then Skegit Valley (10th March) should have knocked them on the head.
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Rolfe
Adult human female
If that was the case you'd only need one vaccine, you wouldn't need to develop separate ones for every condition! I don't think aluminium hydroxide or Quill-A are quite that powerful on their own!
Rolfe
Adult human female
The main difficulty with this virus is human behaviour. Drilling down into it, this is mainly because of asymptomatic, oligosymptomatic and presymptomatic spread. SARS was defeated because people aren't infectious before they start to show symptoms, and it tends to fell people pretty fast, before they've had the chance to pass it on to many others. Once the word is out that people who don't feel well need to isolate and seek medical attention you're well on the way to winning. With this one, people can pass it on while they feel well, or think they only have a bit of a cold. It takes a lot more self-discipline than many people have to adhere to strict biosecure behaviour when they feel fine.
If everybody did exactly as they were told and there was sufficient high-quality PPE to allow everyone who is sick or who needs personal care to be nursed safely, this would be gone by now. It's not happening and it's not going to happen. Individual countries can eliminate it, we've seen that, but they're always vulnerable to reintroduction from international travellers and we've seen that too.
We don't just need a vaccine, we need the vaccine to be used intelligently in a sructured global eradication campaign by the WHO so that the last traces are hunted down and extirpated even in the most difficult regions. They'll probably have to divert resources from the polio eradication campaign to do it.
The Swedes insist that it isn't really infectious as long as you don't have any symptoms, which ruins the idea that "If everybody did exactly as they were told ..." since they still tell people who have been present at potential super-spreader events to get tested if they have symptoms but not if they don't.
Rolfe
Adult human female
I think that one has been pretty well knocked on the head but there seem to be people in Sweden who are somewhat in denial of reality.
In fact the difference between asymptomatic and oilgosymptomatic is a bit artificial. If you only realise in hindsight that you've been a bit off-colour, what use is that? The singers in the Skagit Valley Chorale were asked by email not to show up if they didn't feel entirely well. In fact only half the choir turned up at all that night, presumably because the rehearsal failed many people's personal risk assessments. The original reports of the event said that nobody was symptomatic. It's only when you get to the later more detailed reports that you find there was someone there with mild cold symptoms, who hadn't thought anything of it at the time.
Someone commented that if you could simply shut every human being on earth up in a separate room for two weeks (the same two weeks, obvs) the virus would be gone. You can't, though.
In fact the difference between asymptomatic and oilgosymptomatic is a bit artificial. If you only realise in hindsight that you've been a bit off-colour, what use is that? The singers in the Skagit Valley Chorale were asked by email not to show up if they didn't feel entirely well. In fact only half the choir turned up at all that night, presumably because the rehearsal failed many people's personal risk assessments. The original reports of the event said that nobody was symptomatic. It's only when you get to the later more detailed reports that you find there was someone there with mild cold symptoms, who hadn't thought anything of it at the time.
Someone commented that if you could simply shut every human being on earth up in a separate room for two weeks (the same two weeks, obvs) the virus would be gone. You can't, though.
lomiller
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Covid-19 does infect dogs, cats, ferrets and hamsters. While cat-human transmission hasn’t been documented cat to cat and human to cat transmission has, so it’s reasonable to expect cat’s can infect humans as well. Cats also seem to remain largely asymptomatic while spreading the virus to each other. Animals do not seem to be a major factor in spreading the disease but they serve as a reservoir for the virus to cross back over into the human population.
Another issue is that immunity in Corona viruses tends to be relatively short-lived. 1-3 years is a reasonable expectation in which case eliminating it would require vaccinating every person on earth every year or two.
Rolfe
Adult human female
As far as I know cats have not been shown to be a significant driver of this epidemic in any meaningful way. As you say, nobody has been shown to have caught it from a cat and cats are not themselves seriously ill if they catch it. Maybe this will change as more information is gathered but at present I don't see cats as an animal reservoir fuelling or re-seeding this pandemic.
The point about the possibly short-lived immunity is exactly why you need to use the vaccine to eradicate the disease, not as a panacea. We do this all the time in veterinary disease control. Vaccinate in the face of a threat, but simultaneously work towards eradication, in which endeavour the vaccine is a significant help, then once it's done, no need to vaccinate.
Doing this right probably involves developed countries eradicating it within their borders and a growing system of travel vaccination requirements to visit or come in from a non-eradicated country. It's part of the WHO's remit to support less advantaged countries in their eradication efforts, and then to get in there and finish the job if necessary. I just hope we don't have problems with that like we've had in Pakistan and Nigeria with polio. But this is a lot easier to get rid of than polio I think.
lomiller
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We can’t conclude that no one has caught the virus this way, it just doesn’t seem to be very common relative to other types of transmission. There are cases of the virus speeding between locked down apartments in China (China had real and in some cases literal lockdowns) that would be nicely explained by infected cats or other critters moving back and forth.
While it may be too early to draw conclusions either way given the mild symptoms and short lived immunity it seems like feral cats are very likely an ideal animal reservoir for COVID-19. Even if they don’t show obvious symptoms cats to get sick enough to spread it to each other, so it seems unlikely they couldn’t spread it to humans as well. (would you let another human lick your hand?) IMO mild symptoms and short lived immunity and large feral communities seem to make cats a readymade animal reservoir for COVID-19.
Rolfe
Adult human female
Well, I did say that could change if further information emerged. If there is the potential for the virus to develop an animal reservoir that's an even bigger incentive to get rid of it before that happens. See bovine TB and badgers. However at the moment there does not seem to be any evidence of such a reservoir affecting the course of the pandemic.
The Atheist
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That is truly fascinating. Needs more work, but could be a huge difference if it's that simple.
It does make the people wearing masks under their nose even funnier.
Just an update on this: I talked to my Physician Assistant today and she said that about twenty percent of infections are missed by the swab test I had. That's much higher than I thought. I would have guessed two to five percent. From a Bayesian standpoint, that makes it much more probable that I actually did have Covid-19. Getting blood work next week to rule out some other possibilities.
TellyKNeasuss
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60,000+!!! Making America contaGious Again
Sure, but it's only because the US is testing. If no tests were done, no cases would be found.
I worry about if and when the death rate starts climbing again.
Don't make me read something I can't understand anyway. Is the conclusion that people contract covid primarily by inhaling aerosols? If that's the case, why wouldn't masks over the nose be at least somewhat effective? Apparently medical workers who spend their time in close contact with covid patients but who wear surgical (not N95) masks are less likely to ge sick than the general population with ordinary social contact.
And if we need to not breathe through our noses, maybe swimmers nose clips would make more sense than plugs.
https://www.amazon.com/Speedo-75310...search-10&pf_rd_t=BROWSE&pf_rd_i=3418821&th=1
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