The One Covid-19 Science and Medicine Thread

[Loss Leader]

Multiple threads have been opened in this Science section regarding the novel corona virus. They cross each other frequently, making it difficult to decide in which thread a comment should go. This thread has been opened for all discussions of the science, math, medicine and technology related to our current pandemic.

All other threads have been closed. The threads have not been merged because it would create a chaos of cross-talk and confused timelines. However, members should feel free to quote from those closed threads and continue those discussions here.

Other aspects of the virus - such as the political decisions being made around the world, the economy, personal anecdotes and anything not related to this subform - are off topic. The posts will be sent to AAH and infractions or harsher mod actions will ensue. This shall constitute a Modbox Warning.

We look forward to a spirited discussion among our science-minded members and those looking to learn.

Thank you.

Replying to this modbox in thread will be off topic  Posted By: Loss Leader

 

[marting]

Los Angeles County is doing serological testing to determine the extent of exposed/infected v actual case rates and fatality rates. Question came re today's Stanford study that implies a IFR around .2%

Response was that they would be discussing this joint/USC study in detail next Monday.

Question is at 30:45 into the press conference.
https://www.youtube.com/watch?v=7sHs5MJRi10

 

[novaphile]

No, I still think it's likely that it will be very largely under control in the US by then. I also think there will be much fewer deaths than have been predicted by many. Of course it's now apparent we'll be talking about it for a long time, but i think it will be talking about the economic fallout, the response, future possible pandemics, etc.

Now, any answer to the question you quoted? The Johns Hopkins site still doesn't seem to be showing 30K deaths in the US. Am I looking in the wrong place?

Yes, you're looking in the wrong place.

Johns Hopkins is currently showing for the USA:

    36,721 deaths;
  692,169 confirmed cases;
    58,437 recovered;
3,541,368 tested; and,
   111,972 currently in hospital.

 

[TellyKNeasuss]

Deleted due to not having checked the date of the article the post was discussing.

 

[The Atheist]

Los Angeles County is doing serological testing to determine the extent of exposed/infected v actual case rates and fatality rates. Question came re today's Stanford study that implies a IFR around .2%

Well, if that holds up it seems to indicate the numbers infected aren't vastly more than we're seeing.

 

[casebro]

Los Angeles County is doing serological testing to determine the extent of exposed/infected v actual case rates and fatality rates. Question came re today's Stanford study that implies a IFR around .2%

Response was that they would be discussing this joint/USC study in detail next Monday.

Question is at 30:45 into the press conference.
https://www.youtube.com/watch?v=7sHs5MJRi10

"85 times as many people have had the virus as they had thought"? So mortality rate is not 4%, but 1/85 of 4%, but we all know my maths.... Herd immunity, here we come!

 

[EHocking]

Perhaps, then, if it does come down to male-female explanation, maybe it is not so much that women are necessarily more competent, or that men are necessarily more incompetent, but that if a leader is incompetent, that leader is more likely to be a man.

There could be a scientific reason for that!

The scientific reason is - simple maths.

Consider that, of the 138 countries in the world, only 14 are headed by women, there is a 90% chance that the head of a country will be a man.

So there is also the 90% probability that if a country’s leader is competent it will be a man.

 

[Samson]

From the Chinese study posted by Nessie in the closed thread:

Our study does not rule out outdoor transmission of the virus. However, among our 7,324 identified cases in China with sufficient descriptions, only one outdoor outbreak involving two cases occurred in a village in Shangqiu, Henan. A 27-year-old man had a conversation outdoors with an individual who had returned from Wuhan on 25 January and had the onset of symptoms on 1 February.

https://www.medrxiv.org/content/10.1101/2020.04.04.20053058v1.full.pdf

This looks useful to say the least

 

[Ulf Nereng]

Here's something I found interesting:

Dag Berild, a medical doctor and Associate Professor at Oslo University Hospital, argued that the low level of antibiotic resistant bacteria in Norwegian hospitals may also have played a role in the country's lower mortality rate.

"The argument for that is that many of the coronavirus pneumonia cases are complicated by bacterial pneumonia, so if that is the case with coronavirus, then patients in a country with a low resistance rate among bacteria would have a better prognosis than those in Italy, where they have an awful lot of resistant bacteria, particularly in Lombardy."

The article is about Norway's testing capacity which some may also find interesting:

https://www.thelocal.no/20200403/how-has-norway-managed-to-test-so-many-for-coronavirus

 

[Skeptical Greg]

Yes, you're looking in the wrong place.

Johns Hopkins is currently showing for the USA:

    36,721 deaths;
  692,169 confirmed cases;
    58,437 recovered;
3,541,368 tested; and,
   111,972 currently in hospital.

That's over 400k/~60% of confirmed cases not accounted for ( dead, hospitalized or recovered )..

What does that mean?

 

[Ulf Nereng]

That's over 400k/~60% of confirmed cases not accounted for ( dead, hospitalized or recovered )..

What does that mean?

It just means that they are at home, self-isolating (hopefully).

 

[marting]

From the Chinese study posted by Nessie in the closed thread:

Our study does not rule out outdoor transmission of the virus. However, among our 7,324 identified cases in China with sufficient descriptions, only one outdoor outbreak involving two cases occurred in a village in Shangqiu, Henan. A 27-year-old man had a conversation outdoors with an individual who had returned from Wuhan on 25 January and had the onset of symptoms on 1 February.

https://www.medrxiv.org/content/10.1101/2020.04.04.20053058v1.full.pdf

This looks useful to say the least

Yes, and it makes sense too. The probabilities of spread outdoors are extremely low unless you are in some rowdy group. OTOH, mass transit where you are sardines in a can or grouped indoors like nursing homes is really risky.

Also the study shows the obvious. That most infections are in families and close living groups like cruise ships and aircraft carriers. At least most of the sailors on the latter are young and are at little risk even if they get the bug.

 

[TellyKNeasuss]

Los Angeles County is doing serological testing to determine the extent of exposed/infected v actual case rates and fatality rates. Question came re today's Stanford study that implies a IFR around .2%

Response was that they would be discussing this joint/USC study in detail next Monday.

Question is at 30:45 into the press conference.
https://www.youtube.com/watch?v=7sHs5MJRi10

Did they query the people they were testing as to whether they had, or thought that they might have had, symptoms? At least for the Santa Clara County survey, it didn't sound like they did.

I'm wondering whether Santa Clara County is representative. I believe that only about 0.05 percent of the residents tested positive, which is about a quarter of the national average.

 

[rjh01]

Here's something I found interesting:

Dag Berild, a medical doctor and Associate Professor at Oslo University Hospital, argued that the low level of antibiotic resistant bacteria in Norwegian hospitals may also have played a role in the country's lower mortality rate.

"The argument for that is that many of the coronavirus pneumonia cases are complicated by bacterial pneumonia, so if that is the case with coronavirus, then patients in a country with a low resistance rate among bacteria would have a better prognosis than those in Italy, where they have an awful lot of resistant bacteria, particularly in Lombardy."

The article is about Norway's testing capacity which some may also find interesting:

https://www.thelocal.no/20200403/how-has-norway-managed-to-test-so-many-for-coronavirus

This suggests that the lockdown should be modified. You are allowed to do what you want as long as you do it outside and respect the 1.5 meter rule.

 

[marting]

Did they query the people they were testing as to whether they had, or thought that they might have had, symptoms? At least for the Santa Clara County survey, it didn't sound like they did.

I'm wondering whether Santa Clara County is representative. I believe that only about 0.05 percent of the residents tested positive, which is about a quarter of the national average.

No idea. They did suggest that the expected results that would be different numbers but more or less consistent with Stanford's results. I'm going to make a point of following up Monday. My major concern with serological tests is false positive rates. Especially critical when looking at small percentages. So I'm somewhat skeptical at this time.

 

[Skeptic Ginger]

None of the antibody tests have had anything close to adequate testing to verify sensitivity and specificity. That is probably true worldwide as well but I'm only familiar with the tests being used in the US.

 

[casebro]

.....My major concern with serological tests is false positive rates. Especially critical when looking at small percentages. So I'm somewhat skeptical at this time.

The nasal swab positive rate among patients with symptoms is only about 8%. Which leaves room for lots of serum true positives. 85x 8% is not a small number.

Got any numbers for false positives on equivalent tests? Isn't HIV about 5%?

85x is given for the Stanford study, the L.A. study is not as high, but of similar magnitude. And more random, and larger sample size. I eagerly await our Serological Overlord.

 

[Ulf Nereng]

Yes, and it makes sense too. The probabilities of spread outdoors are extremely low unless you are in some rowdy group. OTOH, mass transit where you are sardines in a can or grouped indoors like nursing homes is really risky.

Also the study shows the obvious. That most infections are in families and close living groups like cruise ships and aircraft carriers. At least most of the sailors on the latter are young and are at little risk even if they get the bug.

I think this result is with everybody wearing masks outside, though.

 

[rjh01]

None of the antibody tests have had anything close to adequate testing to verify sensitivity and specificity. That is probably true worldwide as well but I'm only familiar with the tests being used in the US.

I cannot understand how they could measure the accuracy of these antibody tests. Like the result of a test is positive. Does it mean the person has had the virus or is it a false positive? All they can do is test people who have recently recovered and if their test is negative then probably something is wrong with the test.

To find known negative cases they can go into nursing homes where they know that no one has had the virus and test these people. If they come out positive then it is a good indication that the test is faulty.

 

[pipelineaudio]

The more I listen to these virologists the more they talk about not so much anti virals or fighting the virus but talking about modifying how the body deals with it. it seems like the body starts to get good at fighting the virus then at the same time starts fighting itself badly. So it seems like we should be hearing a lot more about anti inflammatories and immune suppressors. We do hear a lot about steroids bad at the start of infection but good at later stages. What does Tocilizumab do?