Coronavirus thread

[DavidW]

Concerning the parallel to flu vaccines, the point is made that covid-vaccines work more effectively on an individual, than flu-vaccines do, which will also influence the ability to spread the virus.

In both cases the rapidity in which a virus can mutate makes it difficult to know or predict future efficacy rates.  Case in point, the efficacy of the various vaccines for the South African variant is not well known.  And with several major strains already present, who knows what the next mutations hold?  My point is that we are talking about moving targets. 

[MusicTurner]

Yes, that's right. We have no evidence which says that people, who are vaccinated and gets a milder infection, do not transmit the disease to others. Theoretically though they will excrete lesser quanta of virus and therefore tend to be less contagious .

It's not just theoretically, but it's early, and the data aren't comprehensive.

https://www.nature.com/articles/d41586-021-00450-z

"... Preliminary analyses suggest that at least some vaccines are likely to have a transmission-blocking effect ... (...) (Israel:) one team observed a significant drop in viral load in a small number of people infected with SARS-CoV-2 in the two to four weeks after receiving their first dose of the Pfizer vaccine, compared with those who caught the virus in the first two weeks after the injection2. "The data is certainly intriguing and suggestive that vaccination may reduce the infectiousness of COVID-19 cases (...) The Oxford–AstraZeneca trial also observed a larger reduction in viral load in a small group of vaccinated participants than in the unvaccinated group.


https://www.isglobal.org/en/covid-19-novedades-cientificas

((Israel) ..." preliminary results show a significant decrease in viral load among people over 60 years of age, one month after the vaccination rollout started in this age group. This suggests that vaccination may also impact on transmission." (...) (Catalonia:) Another analysis of 282 COVID-19 cluster (...) shows that the viral load was a leading driver of SARS-CoV-2 transmission. People with low viral load infected 12% of their contacts, while people with high viral load infected 24% of their contacts.)

[prémont]

It's not just theoretically, but it's early, and the data aren't comprehensive.

https://www.nature.com/articles/d41586-021-00450-z

"... Preliminary analyses suggest that at least some vaccines are likely to have a transmission-blocking effect ... (...) (Israel:) one team observed a significant drop in viral load in a small number of people infected with SARS-CoV-2 in the two to four weeks after receiving their first dose of the Pfizer vaccine, compared with those who caught the virus in the first two weeks after the injection2. "The data is certainly intriguing and suggestive that vaccination may reduce the infectiousness of COVID-19 cases (...) The Oxford–AstraZeneca trial also observed a larger reduction in viral load in a small group of vaccinated participants than in the unvaccinated group.


https://www.isglobal.org/en/covid-19-novedades-cientificas

((Israel) ..." preliminary results show a significant decrease in viral load among people over 60 years of age, one month after the vaccination rollout started in this age group. This suggests that vaccination may also impact on transmission." (...) (Catalonia:) Another analysis of 282 COVID-19 cluster (...) shows that the viral load was a leading driver of SARS-CoV-2 transmission. People with low viral load infected 12% of their contacts, while people with high viral load infected 24% of their contacts.)

Thanks for the update. If this holds true it is good news.

[prémont]

It's not just theoretically, but it's early, and the data aren't comprehensive.

https://www.nature.com/articles/d41586-021-00450-z

But still the authors of this article conclude:

But whether these observed reductions in viral load are sufficient to make someone less infectious in real life is not yet clear, say researchers.

[MusicTurner]

But still the authors of this article conclude:

But whether these observed reductions in viral load are sufficient to make someone less infectious in real life is not yet clear, say researchers.

Yes. And of course, the second, quoted text then suggests otherwise. That's also why I included it, a study from The Lancet this month.

[Brian]

Tens of thousands of appointments here got delayed due to our crazy weather, so my (and everyone else in the area's) estimated wait time just got an extra week added.

[prémont]

Yes. And of course, the second, quoted text then suggests otherwise. That's also why I included it, a study from The Lancet this month.

Yes, I have read it afterwards. It seems, that there are strong indications to support the claim, but more investigations need to be made. Good news BTW.

[Todd]

Tens of thousands of appointments here got delayed due to our crazy weather, so my (and everyone else in the area's) estimated wait time just got an extra week added.

I would not be surprised if you experience one or two or three more delays. 

An no less a celebrity than Tony Fauci now says that young kids won't get vaccinated until 2022: Anthony Fauci now says elementary students won't get vaccinated until early 2022, after high schoolers in fall

So herd immunity in the US is at least one year away.  Should we start a pool on whether it takes until Q2 2022?

[Mandryka]

One thing I just heard on French TV was interesting, I've not checked to see if it's true.

Apparently this winter has seen a dramatic reduction in flu and gastroenteritis, presumably because people are washing their hands and not getting close to each other.

But we have NOT seen a reduction in COVID. Why not?

The proposed answer was that flu and gastroenteritis viruses are very fragile, they don't survive for long on surfaces, but COVID does.

And so, the suggestion is,  people are picking them up from touching surfaces - and the obvious place is the supermarket trolley. The handles are touched by many people and they are not cleaned systematically.

I for one will be wiping mine down next time I go.

[prémont]

And so, the suggestion is,  people are picking them up from touching surfaces - and the obvious place is the supermarket trolley. The handles are touched by many people and they are not cleaned systematically.

I for one will be wiping mine down next time I go.

The second reference in MusicTurner's post above writes:

It is now clear that SARS-CoV-2 is transmitted predominantly through the air, by people talking and breathing out large droplets and aerosols. In contrast, catching the virus by touching infected surfaces seems to be rare.

BTW I never use the supermarket trolleys, but bring with me my own bag for the purpose.

[T. D.]

The second reference in MusicTurner's post above writes:

It is now clear that SARS-CoV-2 is transmitted predominantly through the air, by people talking and breathing out large droplets and aerosols. In contrast, catching the virus by touching infected surfaces seems to be rare.

BTW I never use the supermarket trolleys, but bring with me my own bag for the purpose.

I have also seen stories asserting the passage in bold above.
But just to be safe, I always wear disposable gloves when shopping (keep a large box thereof in the car). One shop I frequent furnishes free latex gloves and requires their use.

[DavidW]

It is now clear that SARS-CoV-2 is transmitted predominantly through the air, by people talking and breathing out large droplets and aerosols. In contrast, catching the virus by touching infected surfaces seems to be rare.

It seems like we've known this for many, many months now too.

[Pohjolas Daughter]

One thing I just heard on French TV was interesting, I've not checked to see if it's true.

Apparently this winter has seen a dramatic reduction in flu and gastroenteritis, presumably because people are washing their hands and not getting close to each other.

But we have NOT seen a reduction in COVID. Why not?

The proposed answer was that flu and gastroenteritis viruses are very fragile, they don't survive for long on surfaces, but COVID does.

And so, the suggestion is,  people are picking them up from touching surfaces - and the obvious place is the supermarket trolley. The handles are touched by many people and they are not cleaned systematically.

I for one will be wiping mine down next time I go.

At my co-op, they are extremely diligent:  line outside for people to stand 6' apart; hand sanitizer next to the entrance which they ask you to use before entering with gloves also available inside the inner door; they spray and wipe the cart handles before putting them back inside the store for incoming customers (they also have a kind of semi-portable hand wash stand just inside if you want to use it instead of hand sanitizer).  One supermarket does have someone to spray your cart if requested.  At a slightly smaller supermarket, you need to do it yourself.

[Mandryka]

It seems like we've known this for many, many months now too.

It is something that governments have been reluctant to take on board partly because of the cost to themselves (e.g. installing ventilation in schools) but mainly because of the cost to their backers (e.g. installing ventilation in the workplace.) Much better to put the focus on hand washing and face coverings,  then you can blame the public rather than their employers if it goes pear shaped. Capitalism in action.

[DavidW]

It is something that governments have been reluctant to take on board partly because of the cost to themselves (e.g. installing ventilation in schools) but mainly because of the cost to their backers (e.g. installing ventilation in the workplace.) Much better to put the focus on hand washing and face coverings,  then you can blame the public rather than their employers if it goes pear shaped. Capitalism in action.

I learned that fact directly from the CDC many months ago.  There is no government conspiracy at play.  Face coverings do protect against aerosols like covid.  Please don't lump them in together or be an anti-masker.  Masks and social distancing is the top most effective preventative measures that we can take.

[Mandryka]

Masks . . .  is the top most effective preventative measures that we can take.

Is there any evidence for this?  I mean for the sort of face coverings people actually use, the way they actually use them, while going about their daily business?

[Irons]

Is there any evidence for this?  I mean for the sort of face coverings people actually use, the way they actually use them, while going about their daily business?

If nothing else masks remind us to be cautious with our interactions in daily life. Invaluable for that alone.

[MusicTurner]

Info here in DK is that the standard paper masks typically protect against 63% of potential virus particles, and if combined with a good textile mask (but much less convenient of course), it's 92%.

Textile masks can be of poor quality, down to 30-40%, and people tend to re-use them too much. Authorities here will be introducing official markings for those guaranteeing an effect of 60-70%.

[prémont]

Info here in DK is that the standard paper masks typically protect against 63% of potential virus particles, and if combined with a good textile mask (but much less convenient of course), it's 92%.

As I have read some time ago (don't recall where, but it was a Danish site) the standard masks protect relatively well against droplets but not so much against aerosols. Droplets fall rather fast to the floor, but aerosols can remain floating in the air for hours. This is why ventilation is important, and why the length of time one stays indoor is important. The longer time, the more aerosols you inhale to the lungs.

[Mandryka]

Info here in DK is that the standard paper masks typically protect against 63% of potential virus particles, and if combined with a good textile mask (but much less convenient of course), it's 92%.

Textile masks can be of poor quality, down to 30-40%, and people tend to re-use them too much. Authorities here will be introducing official markings for those guaranteeing an effect of 60-70%.

Which standard of paper mask? How long do they protect at that level for? What happens if they're touched? Reworn after a few hours? What about non standard masks? What if they're not worn properly?

I've got a paper mask in my pocket, I'm not sure if it meets a standard, bought cheap ones from Amazon months ago, it has been in my pocket for about two months, rubbing against my wallet and keys, I get it out when I go into a shop, it seems to keep everyone happy.