Corona virus general questions mega thread

[MigL]

Could also be due to travel patterns.
More affluent West Germans, especially from the southern regions, will go on skiing vacations in the Italian/Swiss/Austrian Alps, in January or February. That area seems to be the epicenter of the central European infection.

[CharonY]

1 hour ago, StringJunky said:

Could it be East Germans are more likely to snitch on their neighbours and so there's more paranoia there?? Your post reminded of this Reuters article I read today:

https://www.reuters.com/article/us-health-coronavirus-germany-denunciati/germans-snitch-on-neighbours-flouting-virus-rules-in-echo-of-the-stasi-past-idUSKBN21K2PB

It's a WAG on my part but it seems plausible in a casual way.

 

There are easier explanations. The first is that in some states there was earlier spread from folks that returned from holidays and there were carnival festivities resulting in major infections in NRW. In Baden-Wuertemberg folks travelling from Italy were diagnosed with COVID-19 in February for example.

Another element is that aside from major cities the population density in East Germany is fairly low (unless it has changed in recent years) and I would think that together with spread pattern it could account for most of the differences. There are also differences in the length and time of winter holidays in the different states, so depending on when they are, there might also be different timing in when folks returned from holidays. Those coming back earlier might have evaded infection in Italy, for example, in addition to the point MigL made..

[StringJunky]

22 minutes ago, CharonY said:

There are easier explanations. The first is that in some states there was earlier spread from folks that returned from holidays and there were carnival festivities resulting in major infections in NRW. In Baden-Wuertemberg folks travelling from Italy were diagnosed with COVID-19 in February for example.

Another element is that aside from major cities the population density in East Germany is fairly low (unless it has changed in recent years) and I would think that together with spread pattern it could account for most of the differences. There are also differences in the length and time of winter holidays in the different states, so depending on when they are, there might also be different timing in when folks returned from holidays. Those coming back earlier might have evaded infection in Italy, for example, in addition to the point MigL made..

OK cheers.

[CharonY]

Another random  thought regarding SARS-Cov vs SARS-cov2 is that the latter is much less virulent. But in this case it does show how reduced virulence actually leads to far wider spread.

[J.C.MacSwell]

5 hours ago, CharonY said:

Another random  thought regarding SARS-Cov vs SARS-cov2 is that the latter is much less virulent. But in this case it does show how reduced virulence actually leads to far wider spread.

Is this then an example of a well known trend? 

[dimreepr]

28 minutes ago, J.C.MacSwell said:

Is this then an example of a well known trend? 

Makes sense, if all you get is a cold it's free to roam, at the other end of the spectrum, if the virus kills, it not only lose's a host but potential hosts soon learn to avoid the guy with a runny nose.

[Sensei]

  

10 hours ago, CharonY said:

There are also differences in the length and time of winter holidays in the different states, so depending on when they are, there might also be different timing in when folks returned from holidays. Those coming back earlier might have evaded infection in Italy, for example, in addition to the point MigL made..

 

13 hours ago, Sensei said:

 

The list of school holidays in Germany with their dates per region:

Baden-Württemberg --
Bavaria school February 24 - February 28, 2020
Berlin school February 3 - February 8, 2020
Brandenburg February 3 - February 8, 2020
Bremen February 3 - February 4, 2020
Hamburg January 31, 2020
Hesse --
Lower Saxony February 3 - February 4, 2020
Mecklenburg-West Pomerania February 10 - February 21, 2020
North-Rhine Westphalia : --
Rhineland Palatinate February 17 - February 21, 2020
Saarland February 17 - February 25, 2020
Saxony February 10 - February 22, 2020
Saxony-Anhalt  February 10 - February 14, 2020
Schleswig-Holstein  --
Thuringia February 10 - February 14, 2020

Reference https://www.iamexpat.de/education/primary-secondary-education/school-holiday-dates-germany

 

Edited April 3, 2020 by Sensei

[dimreepr]

3 minutes ago, Sensei said:

The list of school holidays in Germany with their dates per region:

Why???

Did I miss something?

[J.C.MacSwell]

27 minutes ago, dimreepr said:

Makes sense, if all you get is a cold it's free to roam, at the other end of the spectrum, if the virus kills, it not only lose's a host but potential hosts soon learn to avoid the guy with a runny nose.

That's a good argument. I'm just asking if it has been verified to any degree. When it only kills a small percentage of the hosts, and those killed off still last a substantial time the others would be contagious, I would not expect it to be a major driver...as in statistically difficult to correlate.

[dimreepr]

9 minutes ago, J.C.MacSwell said:

That's a good argument. I'm just asking if it has been verified to any degree. When it only kills a small percentage of the hosts, and those killed off still last a substantial time the others would be contagious, I would not expect it to be a major driver...as in statistically difficult to correlate.

I'm guessing influenza, is walking the tight-rope like a pro...

This guy is ten times more potent (ially, likely to fall off the rope).

Edited April 3, 2020 by dimreepr

[J.C.MacSwell]

27 minutes ago, dimreepr said:

I'm guessing influenza, is walking the tight-rope like a pro...

This guy is ten times more potent (ially, likely to fall off the rope).

You could be right. Too much spreadability could also be disadvantageous to the virus's long term "health", as it should lead more quickly to herd immunity (for whatever herd might host it)

[dimreepr]

10 minutes ago, J.C.MacSwell said:

You could be right. Too much spreadability could also be disadvantageous to the virus's long term "health", as it should lead more quickly to herd immunity (for whatever herd might host it)

A good analog is, the more time it has the more chance it has to evolve.

Which depends, of course, on the size of the herd...

[CharonY]

2 hours ago, J.C.MacSwell said:

That's a good argument. I'm just asking if it has been verified to any degree. When it only kills a small percentage of the hosts, and those killed off still last a substantial time the others would be contagious, I would not expect it to be a major driver...as in statistically difficult to correlate.

It is a common observation that pathogens with long evolutionary history tend to become less virulent. Our genomes are quite full with dormant viral sequences, indicating that at some point they just became part of us. There is an assumption that there is an optimum on what level is the optimum, depending on a variety of host-pathogen factors (e.g. resistance). 

There has also been experimental evidence in simple systems. However, due to the nature of interact there can be cases where virulence can increase (but again, the current outbreak does show how effective tempering virulence can be). 

It also means that pathogens jumping hosts are often maladapted and may have suboptimal virulence (e.g. too high).

[13mh13]

Why is the question "How many virus(es) - -corona , etc -- does it take cause infection" so across-the-board with responses?

https://www.quora.com/How-many-individual-virus-are-needed-to-start-an-infection-Will-1-flu-virus-be-enough-to-make-you-sick-or-do-you-need-many-more-than-that

[CharonY]

10 minutes ago, 13mh13 said:

Why is the question "How many virus(es) - -corona , etc -- does it take cause infection" so across-the-board with responses?

https://www.quora.com/How-many-individual-virus-are-needed-to-start-an-infection-Will-1-flu-virus-be-enough-to-make-you-sick-or-do-you-need-many-more-than-that

AFAIK the minimal infectious dose for SARS-Cov2 has not been established yet. I.e. no one knows yet.

[StringJunky]

6 minutes ago, CharonY said:

AFAIK the minimal infectious dose for SARS-Cov2 has not been established yet. I.e. no one knows yet.

On the subject of dose, I saw this recent paper that suggests the severity of the outcome may be tied to initial viral load:

Quote

Viral dynamics in mild and severe cases of COVID-19

....Nasopharyngeal swabs from both the left and right nasal cavities of the same patient were kept in a sample collection tube containing 3 mL of standard viral transport medium. All samples were collected according to WHO guidelines.5 The mean viral load of severe cases was around 60 times higher than that of mild cases, suggesting that higher viral loads might be associated with severe clinical outcomes. We further stratified these data according to the day of disease onset at the time of sampling. The DCt values of severe cases remained significantly lower for the first 12 days after onset than those of corresponding mild cases (figure A). We also studied serial samples from 21 mild and ten severe cases (figure B). Mild cases were found to have an early viral clearance, with 90% of these patients repeatedly testing negative on RT-PCR by day 10 post-onset. By contrast, all severe cases still tested positive at or beyond day 10 post-onset. Overall, our data indicate that, similar to SARS in 2002–03,6 patients with severe COVID-19 tend to have a high viral load and a long virus-shedding period. This finding suggests that the viral load of SARS-CoV-2 might be a useful marker for assessing disease severity and prognosis....

https://www.thelancet.com/journals/laninf/article/PIIS1473-3099(20)30232-2/fulltext

 

[CharonY]

Just now, StringJunky said:

On the subject of dose, I saw this recent paper that suggests the severity of the outcome may be tied to initial viral load:

Yes there are some conflicting results. A few studies from Italy and China indicate no difference in the load between asymptomatic and severe patients, for example. Another one suggests that the load is only different in swabs. Also animal studies with other coronaviruses  suggest worse outcome with higher loads. As with anything, the knowledge is very much in flux. 

[Danijel Gorupec]

Thanks StringJunky and CharonY... But I was not able to understand what do you exactly mean by 'initial viral load' - would this be exposure load or a measured load at (or near) onset of symptoms?

[StringJunky]

13 minutes ago, Danijel Gorupec said:

Thanks StringJunky and CharonY... But I was not able to understand what do you exactly mean by 'initial viral load' - would this be exposure load or a measured load at (or near) onset of symptoms?

Load at exposure.

[13mh13]

5 hours ago, 13mh13 said:

Why is the question "How many virus(es) - -corona , etc -- does it take cause infection" so across-the-board with responses?

https://www.quora.com/How-many-individual-virus-are-needed-to-start-an-infection-Will-1-flu-virus-be-enough-to-make-you-sick-or-do-you-need-many-more-than-that

But it does not prevent sensationalist science  vloggers from taking stabs...

 

[J.C.MacSwell]

Without clicking, I'm going to assume that's enough, targeted, to contaminate all 7 billion of us...but not contaminate the entire Earth enough to infect everyone.

+ 1 though for the snapshot, and especially for calling it sensational.

[13mh13]

2 hours ago, J.C.MacSwell said:

Without clicking, I'm going to assume that's enough, targeted, to contaminate all 7 billion of us...but not contaminate the entire Earth enough to infect everyone.

+ 1 though for the snapshot, and especially for calling it sensational.

No ... not even close  ...not according to the vlogger (who is a scientist: Phil Mason).

Would you please do me a favor. Remove your +1, and either replace w/ -1 or NOTHING. 

That social media LIKE/UNLIKE is not very "scientific" now, is it, toots? And neither is your attitude of not clicking thru video to INVESTIGATE.

 

------ BTW ----------------

A week ago, several of my in-line posts were deleted by Mods because many of you found them EXTREMELY OFFENSIVE. 

Well, for the sake of "science" -- for what THAT'S worth at the putatively scientific forum, SF -- the topic of URINATING (pissing) on ones body parts (or gloves) to sterilize them .... in case you were outta Purell... needs to be resurrected from the mode-deleted posts.

So where's the evidence for Pee-u-rell, you ask ....

https://www.ncbi.nlm.nih.gov/pubmed/2510466

Actually, it's the ammonium salts....fresh outta the bladder being ideal. Get that pH into an anti-viral zone. 

 

Edited April 4, 2020 by 13mh13

[MigL]

OK then...

I'm off to disinfect myself by rolling around in my cats' litter box.
( that really 'reeks' of ammonia )

[Danijel Gorupec]

If it turns out that the viral load at exposure significantly determines the outcome of the illness, then I think it would be fair to recommend to all people who are at risk to wear masks even for their own protection (not only for protection of others). Of course, this comes with educational lines how to do it properly.

As you can see, even on this forum, we talk a lot about mask. In my opinion, this is a because unclear messages were received from professionals. I hope for clearer recommendations eventually. And I hope epidemiological profession will note this small issue into their textbooks.

[J.C.MacSwell]

Seasonal allergies kicking in...is this a good thing if exposed to the virus with the immune system on hyperdrive...a bad thing with the immune system distracted with the extra load...or could go either way?