The coronavirus spread updated in real time

[_EAllusion]

[quote]Context. If my recollection is correct, WHO from the beginning recommended that the sick wear surgical masks when in close contact, like when a health care provider or someone in their household is in the same room. That's different than the current cloth covering practice that's being promoted. If you're an essential worker going to the workplace, unless you don't work in proximity to others, you're wearing the same piece of cloth over your mouth all day. Healthcare workers change their masks with every patient. But these cloth masks can be worn for hours at a time, with people tugging on them to adjust them or repeatedly taking them off and putting them back on. If there is virus on the mask, they're getting it on their hands and spreading it everywhere they touch or on every surface that the masks touch. The concern about germs building up on the mask are why health care professionals use disposable masks. Yet, an ordinary person is supposed to drag around the same germ-ridden piece of cloth all day. That's what hasn't been studied, although I've read concerns expressed about it.[/quote]

The context I'm replying to are early posts in this thread. You in particular seemed really down on mask use, including N95 use. It came up a few times when I reread the early part of the thread. Perhaps I have you mistaken with someone else, but I believe I read you advising that masks are more appropriate if you are sick, but otherwise forgo them. But if they're appropriate if you're sick, then they're appropriate if you might be sick. It's just casting a wider net.

Unpacking your comments here, my partner at one point was down to being issued two masks to have indefinitely. Then was upgraded to one mask a day. Now things are tentatively better, though there is a warning that reductions could happen if the surge hits. Masks should be one use per patient, but if that's not possible, the judgement is that something is better than nothing.

There's a lot of uncertainty about how effective mask use is for reducing the transmission rate, though it is still standard to advise people to wear them if they think they are sick and by default in a health care setting (with that practice obviously spreading outward.) I take it simply that if it's more plausible to reduce transmission than increase it, which is the case, then in the middle of a sweeping epidemic, you probably should do it.

[_Jersey Girl]

"I don't think you're the one person that gets to make the decision," Paul continued. "We can listen to your advice but there are people on the other side saying there's not going to be a surge and then we can safely open the economy. And the facts will bear this out."

What's the other side? Trump? Fauci has never once said he's the one person who gets to make the decision. He's offered scientifically sound overviews, updates, guidance and now warnings. Wth is Paul talking to him about his making "the decision" for?

The freaking governors (cheered on by President) have made their decisions and are still making them. ALL of them opening not in keeping with CDC guidelines, but in spite of them and prematurely so.

Can none of these people THINK?

[_Res Ipsa]

RI I spoke to my medical practice about the antibody test. They referred me to Lab Corp with my question. Went to the Lab Corp website. Here's one of the links where it discusses the test.

https://www.labcorp.com/antibody-testing

p.s. She said that in order to take the test you have to have had a confirmed case. That's not what they said yesterday and the Lab Corp website doesn't say that at all. I told her I was looking right at it and the only criteria stated was if you think you may have had the virus. This was the front desk I spoke to today. :rolleyes: I'll just have to send a message directly to my PCP and find out about it. You would think the front desk would be well prepared to answer questions on testing. But no.

So, LabCorps doesn’t make a serology test. They use different tests that they buy from the manufacturers. From their website:

LabCorp is providing serology testing based on tests from various manufacturers. Such tests have either received an emergency use authorization (EUA) from the U.S. Food and Drug Administration (FDA) or were released for use under FDA guidance, “Policy for Diagnostic Tests for Coronavirus Disease-2019 during the Public Health Emergency - Immediately in Effect Guidance for Clinical Laboratories, Commercial Manufacturers and Food and Drug Administration Staff” that was updated on May 4, 2020. Tests being performed under an EUA have not been FDA cleared or approved and LabCorp has completed independent validation of these tests. In addition, various manufacturers have submitted or will seek EUA for their tests.

So, I’ve got no idea. Also, I combined some information on antigen tests with antibody tests last night — I shouldn’t try and post complicated stuff late at night. The two kinds of antibody tests are ELIZA and LFA. ELIZA gives you a level of antibody present in your blood and an LFA just gives you a yes, no, or indeterminate.

Here are the tests that have had an EUA and the accuracy information on a which the EUA was based: https://www.fda.gov/medical-devices/eme ... erformance.

The chart for each has a line labeled PPV 5%. The value on that line gives the answer to this question: If 5% of population has COVID antibodies, what is the chance that a positive result on my test would be accurate? Some have very high median values, but the 95% confidence range is very wide. Plus, I would be shocked if the prevalence rate is as high as 5% in your area. The lower the prevalence rate, the lower that PPV number will be. There’s a link to a calculator on that FDA page that lets you input specific numbers and gives you the odds that a positive test is accurate.

Just my opinion, but I would not change any of my behavior based on the test result. At a reasonable estimate of prevalence, I think a large part of that 95% confidence level would be at 50% or below — no better than a coin flip.

On the other hand, the prevalence among the population of people who had symptoms Is certainly higher. But we don’t how much. On the other other hand, if you weren’t in contact with a confirmed case and there wasn’t community spread in your locale, you’re likely part of a population with lower prevalence.

See how nice and clear and straightforward this is?

In Bayesian terms, you have to account for the likelihood that you actually were exposed based on the characteristics of the population you are a member of before you see your test result. When prevalence in the population you are a member of is very low and the test produces false positives, the odds that a positive result is a false positive can get very high. (Rate of false positives = 100% minus that PPV percentage. For example, I gave blood today. If the HIV test on that blood is positive, the odds that the result is a false positive approach 100%.

Also, this is what I understand and I’m happy to share it, but I wouldn’t rely on it without confirmation from Lemmie or Analytics or PG or any other person who knows stats better than I do.

[_Jersey Girl]

Okay, RI. I have to do something before I actually respond to you.

:surprised: :surprised: :surprised: :surprised: :surprised: :surprised: :surprised:


THIS IS ALL BS!!!!!!!!!

[_Jersey Girl]

Okay I'm better now. I wasn't thinking clearly last night posting to you either. Before I went to sleep last night I actually remembered other symptoms I had but, no worries. Let's start at the beginning.

The antigen tests detect active cases.
The antibody tests detect antibodies for CV-19 indicating that you've already had it. In other words, titers.

This is what I figure could have happened in my case. I could have been exposed to someone with a low viral load and in response, developed a low viral load myself. If that were the case then I'm starting to think that the antibody tests would be nothing more than a roll of the dice because don't we need to fight all out war in order to build up enough antibodies? I'm not sure if the experts know the answer to that question as it relates to CV-19 and this is my reasoning. We are hearing reports that people have contracted it a second time. What does that mean? Were they exposed and developed a low viral load...then what, they were exposed to the viral load from hell having never developed substantial antibodies to begin with?

This is way above my pay grade. Ask me how to respond to challenging behaviors. Ask me how to make homemade finger paint.

I would never change what I'm doing based on test results which only begs the question of why get tested to begin with? My answer is some small bit of peace of mind. Not walking on eggshells even when double masked and socially distancing.

I don't even know if it matters though because we're learning about how this virus behaves in real time.

Think about it. In the beginning they were warning people like me who take ACE inhibitors like Lisinopril or ARB's like Losartan that they could cause an up-regulation in the process where all hell could break loose and now they are saying the exact opposite.

I will just ask my PCP when I see her for a lab follow up. There, I've changed my mind how many times already? :confused:

[_EAllusion]

The Daily Beast is reporting on the previously rumored plan to have the CDC start lowering their mortality numbers referring to a pressure campaign by Dr. Birx to adopt a much stricter criteria to revise the count downwards:

https://www.thedailybeast.com/team-trum ... ath-counts

[_Icarus]

The Daily Beast is reporting on the previously rumored plan to have the CDC start lowering their mortality numbers referring to a pressure campaign by Dr. Birx to adopt a much stricter criteria to revise the count downwards:

https://www.thedailybeast.com/team-trum ... ath-counts

So Birx has become a shill for Trump? Fauci just said yesterday the numbers are most certainly an undercount.

[_EAllusion]

[quote]So Birx has become a shill for Trump? Fauci just said yesterday the numbers are most certainly an undercount.[/quote]Uh, she's been shilling for Trump for a while.

This is probably the funniest example:

https://Twitter.com/atrupar/status/1243556939369496576

But that's not isolated.

Dr. Fauci makes compromises for Trump, but they are not as overt. The benefit of the doubt argument for Dr. Birx long has been that she needs to preserve her position to do good within the admin because if she's replaced, it'll be by an even bigger hack loyalist with an even more liberal attitude towards dishonesty that will lead to even more harm. To that, I say that at a certain point the harm of Dr. Birx is providing an air of legitimacy to the Trump admin's actions and positions does greater harm than by her not being there and this logic of compromise is how Trump morally corrupts anyone who sticks in his orbit.

Anywho, Dr. Birx says the CDC numbers can't be trusted, are likely significantly overcounting deaths, and is reported to be leaning on the careerists to revise their methodology so the numbers lower. This, coincidentally, echoes both Trump's now long-standing pattern of trying to downplay coronoavirus numbers, or any numbers that he thinks makes him look bad, and recent reports that the Whitehouse has a deliberate political strategy to try to downplay COVID mortality numbers.

I know this is all about working press expectations and therefore the tone of coverage from a few idiot editors and producers in very influential posts, but if you overlook that part I wonder how anyone can even see that big of a difference in what your political reaction should be between, say, 70k dead and 120k dead.

[_Res Ipsa]

Okay I'm better now. I wasn't thinking clearly last night posting to you either. Before I went to sleep last night I actually remembered other symptoms I had but, no worries. Let's start at the beginning.

The antigen tests detect active cases.
The antibody tests detect antibodies for CV-19 indicating that you've already had it. In other words, titers.

This is what I figure could have happened in my case. I could have been exposed to someone with a low viral load and in response, developed a low viral load myself. If that were the case then I'm starting to think that the antibody tests would be nothing more than a roll of the dice because don't we need to fight all out war in order to build up enough antibodies? I'm not sure if the experts know the answer to that question as it relates to CV-19 and this is my reasoning. We are hearing reports that people have contracted it a second time. What does that mean? Were they exposed and developed a low viral load...then what, they were exposed to the viral load from hell having never developed substantial antibodies to begin with?

This is way above my pay grade. Ask me how to respond to challenging behaviors. Ask me how to make homemade finger paint.

I would never change what I'm doing based on test results which only begs the question of why get tested to begin with? My answer is some small bit of peace of mind. Not walking on eggshells even when double masked and socially distancing.

I don't even know if it matters though because we're learning about how this virus behaves in real time.

Think about it. In the beginning they were warning people like me who take ACE inhibitors like Lisinopril or ARB's like Losartan that they could cause an up-regulation in the process where all hell could break loose and now they are saying the exact opposite.

I will just ask my PCP when I see her for a lab follow up. There, I've changed my mind how many times already? :confused:

I think changing one's mind is healthy, especially in a situation like this where we have a firehose of information, ranging from reliable to complete crap, constantly hitting us in the face. There's what appears to be a pretty solid study that found people who tested positive while symptomatic can continue to test positive for 30 days after symptoms disappear. But a PCR test can only tell you whether there is virus RNA in the sample. It can't tell you whether the virus is capable of replication. So, it could be that the body is slow to shed enough remnants to get below the levels that a PCR test can find. That could explain "reinfections," but its still pretty speculative.

That same study had two sample pools. The first consisted of people who had previously tested positive. The second was people who had never been tested, but had been symptomatic and one of the following: had a doctor say they likely had COVID, lived with someone who tested positive, or were themselves a health care worker.

The people in the first group almost all developed antibodies after 3-4 weeks. Of those in the second group, only 1/3 developed antibodies in the same time frame. That could mean that cases with milder symptoms don't invoke an immune response. Or, it could mean that it's really hard to diagnose a mild case based on symptoms alone.

For me, it's easy. I have no reason to believe I've been exposed. No symptoms. Very few trips out of the house. No clusters, let alone isolated cases, in my family or people I regularly associate with. So, I'm not trying to be tested. I think it makes much more sense give antibody tests to people who tested positive with a PCR test, health care workers who were exposed, and others as part of a surveillance study. But that's just me.

It's way above my paygrade, too. But there are lots of folks on #epitwitter who will take the time to explain as long as you're civil about it.

[_EAllusion]

In a surprise to no one, the Wisconsin Supreme Court has struck down our stay-at-home order.