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kriesel 2020-04-20 19:10

Most Wisconsin counties have no or very fewCovid19 cases. Yet the whole state is under stay at home order for another 5 weeks 18 hours, while businesses suffer or die, students go uneducated, biopsies and other needed medical procedures go unperformed, etc. [URL]https://newstalk1130.iheart.com/featured/common-sense-central/content/2020-04-20-most-of-wisconsin-has-seen-almost-no-coronavirus-cases/[/URL]
Weeks longer than any neighboring state. Wisconsin is doing well compared to most of its neighbors. [url]https://www.worldometers.info/coronavirus/country/us/[/url]

ewmayer 2020-04-20 21:49

Re. antibody tests, I see 2 huge red-flag issues:

[1] Studies involving self-selection, i.e. the people voluteering to be tested are likely showing some kinds of symptoms of flu-like illness, and thus not a representative sample of the population at large;

[2] It seems few or none of the antibody tests currently being used in various parts of the world is "gold standard" reliable - lots of false positives and negatives. I've heard only PCR-based assays have shown the needed reliability, and they are not being done at scale.

Lastly, on the does-exposure-generate-immunity question, here is a useful backgrounder from [url=https://www.npr.org/sections/goatsandsoda/2020/03/20/819038431/do-you-get-immunity-after-recovering-from-a-case-of-coronavirus]NPR[/url]:
[quote]Researchers do know that reinfection is an issue with the four seasonal coronaviruses that cause about 10 to 30% of common colds. These coronaviruses seem to be able to sicken people again and again, even though people have been exposed to them since childhood.

"Almost everybody walking around, if you were to test their blood right now, they would have some levels of antibody to the four different coronaviruses that are known," says Ann Falsey of the University of Rochester Medical Center.

After infection with one of these viruses, she says, antibodies are produced but then the levels slowly decline and people become susceptible again.

"Most respiratory viruses only give you a period of relative protection. I'm talking about a year or two. That's what we know about the seasonal coronaviruses," says Falsey.

In studies, human volunteers who agreed to be experimentally inoculated with a seasonal coronavirus showed that even people with preexisting antibodies could still get infected and have symptoms.

That happens even though these viruses aren't as changeable as influenza, which mutates so quickly that a new vaccine has to be developed every year.

"We work with some common cold coronaviruses. We have samples from 30 years ago, strains that were saved from 30 years ago, and they're not appreciably different than the ones that are circulating now," says virologist Vineet Menachery of the University of Texas Medical Branch in Galveston.

Still, seasonal coronaviruses probably do mutate a bit over time to evade the body's defenses, says Frieman. But there's little known about what those changes might look like, since researchers don't do annual surveillance of coronaviruses as they do for influenza.

It's also possible that, for some reason, the body's immune response to seasonal coronaviruses is just not that robust or that something about the infection itself may inhibit the body's ability to develop long-term immunity.

"Maybe the antibodies are not protective, and that is why, even though they are present, they don't work very well," says Frieman.

The other known human coronaviruses, severe acute respiratory syndrome and Middle East respiratory syndrome, can cause more severe disease, and basically nothing is known about the possibility of reinfection with those viruses.

Some people sickened by SARS, the dangerous coronavirus that emerged in China in 2002, did develop a measurable immune response that lasted a long time.

"We've gone back and gotten samples from patients who had SARS in 2003 and 2004, and as of this year, we can detect antibodies," says Stanley Perlman of the University of Iowa. "We think antibodies may be longer lasting than we first thought, but not in everybody."

Still, it's hard to predict how those survivors' bodies would react if they were exposed to the SARS virus again. "There were 8,000 cases, the epidemic was basically brought to an end within six months or eight months of the first case, so we don't have anyone who was reinfected that we know of," says Perlman.

The other severe coronavirus, MERS, emerged in the Middle East in 2012. "We have almost no information about reinfection because there has only been a total of 2,500 cases over eight years," says Perlman, who notes that the odds of anyone getting reinfected with that virus are not great, especially considering that 35 percent of people who had it died. Survivors of MERS did generate an immune response to the virus that can be detected up to two years later, he says. And the more ill the patient was, the more robust and long-lasting the immune response.

Until the recent emergence of SARS-Cov2, the official name of the current coronavirus, and this pandemic, scientists say, there just hasn't been much of a research push to fully understand how and why reinfection with coronaviruses can occur.

"You get colds over and over again, and I don't think we think that we're really so well protected against any of them, second time around," says Perlman. "You don't care, either, because it's just a cold virus. I mean, you'd like to not get a cold again, but it's not really a big deal."

This pandemic, he notes, "is a big deal."

He would bet that the virus that causes COVID-19 won't reinfect people. But he wouldn't guess how long their immunity might last.

What's more, some people might have stronger protection from reinfection than others.

"Based on other infections where you get a deep lung infection, you are usually protected against the second infection. If you just have a mild COVID-19 infection that involves your upper airway, maybe it will behave like a common cold coronavirus and maybe you can be reinfected again," says Perlman. "We just really don't know. It's even hard to speculate."

Understanding the natural immune response to this virus is important for vaccine development, he notes.

"If the natural infection doesn't do very well in giving you immunity, what is going to happen with the vaccine?" says Perlman. "How are we going to make sure that that vaccine not only induces a response that works for the next six months, but two to three years?"[/quote]

kladner 2020-04-20 21:59

[QUOTE=ewmayer;543308]Re. antibody tests, I see 2 huge red-flag issues:

[1] Studies involving self-selection, i.e. the people volu(n)teering to be tested are likely showing some kinds of symptoms of flu-like illness, and thus not a representative sample of the population at large;

[2] It seems few or none of the antibody tests currently being used in various parts of the world is "gold standard" reliable - lots of false positives and negatives. I've heard only PCR-based assays have shown the needed reliability, and they are not being done at scale.

Lastly, on the does-exposure-generate-immunity question, here is a useful backgrounder from [URL="https://www.npr.org/sections/goatsandsoda/2020/03/20/819038431/do-you-get-immunity-after-recovering-from-a-case-of-coronavirus"]NPR[/URL]:[/QUOTE]
Testing is a true SNAFU. I think the Feds are sitting on supplies for viral testing because Cheeto in Chief would not like the "FAKE NEWS" numbers. He would not have minded sinking a couple of cruise ships to keep "the numbers" down, if he could have gotten away with it.

kriesel 2020-04-21 02:40

[QUOTE=ewmayer;543308]Re. antibody tests, I see 2 huge red-flag issues:

[1] Studies involving self-selection, i.e. the people voluteering to be tested are likely showing some kinds of symptoms of flu-like illness, and thus not a representative sample of the population at large;

[2] It seems few or none of the antibody tests currently being used in various parts of the world is "gold standard" reliable - lots of false positives and negatives. I've heard only PCR-based assays have shown the needed reliability, and they are not being done at scale.[/QUOTE]
I'm curious, what do you base the conclusion of self-selection upon?

In the Santa Clara County study: "Participants were recruited using Facebook ads targeting a representative sample of the county by demographic and geographic characteristics." I read that as they took pains to avoid self-selection type errors.

In the Massachusetts homeless shelter study, they tested all clients of the shelter. Is being in a given homeless shelter self-selection? This testing was by PCR. [URL]https://www.medrxiv.org/content/10.1101/2020.04.12.20059618v1[/URL]

In the Massachusetts sewage system study, the only self-selection that may be occurring is who uses indoor plumbing vs. going on the sidewalk or elsewhere in a way it won't find its way into the sewage system. This study was done by quantitative PCR, by "a team involving scientists from startup Biobot Analytics, the Massachusetts Institute of Technology (MIT), Harvard University, and Brigham and Women's Hospital". If they can't get it right, who can? [URL]https://www.newsweek.com/coronavirus-traces-massachusetts-wastewater-levels-higher-expected-1497141[/URL]

In the Massachusetts random selection on the street study, "While the participants appeared healthy, about half told the doctors that they experienced at least one symptom of COVID-19 in the past four weeks." And a third of the tests of that group showed antibodies. So the rate of antibody production and also experiencing symptoms was somewhwere between zero and up to 2/3. Having had at least one symptom could easily mean they had a bout with a normal flu strain. There's a great deal of symptom overlap, and not enough symptoms to go around among the many diseases and strains. [URL]https://www.foxnews.com/science/third-blood-samples-massachusetts-study-coronavirus[/URL] The Biomedomics test is described here: [URL]https://www.bd.com/en-us/company/news-and-media/press-releases/bd-biomedomics-announce-launch-of-rapid-serology-test-to-detect-exposure-to-covid-19[/URL]
From what I've read, PCR is not applicable to antibodies, it's applicable to DNA and RNA.

The concern and yet to be answered well questions about extent and duration of immunity are included in the link I posted earlier, [URL]https://www.bostonherald.com/2020/04/05/massachusetts-lab-launches-coronavirus-antibody-test/[/URL].

Posted earlier was [URL]https://chicagocitywire.com/stories/530092711-roseland-hospital-phlebotomist-30-of-those-tested-have-coronavirus-antibody[/URL] which indicates 30-50% of those tested at Roseland in Chicago have antibodies, 10-20% live virus, from a combination of in-hospital and drive-up, so some substantial self-selection there.

Same article has a link to Gangelt Germany study article [URL]https://www.bccourier.com/these-are-the-first-lessons-of-the-heinsberg-study/[/URL]
High points: 15% infected, 0.37% fatality probability. "it can be assumed that the severity of the disease could be reduced through hygiene measures." “The number of pathogens affects the severity of the disease in the case of initial infections.” Subject selection method not stated.

It's disappointing how much air time the major media have wasted without getting much of this out or right.

retina 2020-04-21 02:49

[QUOTE=kriesel;543336]I'm curious, what do you base the conclusion of self-selection upon?[/QUOTE]Self selection means someone can decline to participate.

kriesel 2020-04-21 03:09

[QUOTE=retina;543338]Self selection means someone can decline to participate.[/QUOTE]Sounds like self-deselection to me.

retina 2020-04-21 03:18

[QUOTE=kriesel;543339]Sounds like self-deselection to me.[/QUOTE]Same thing.

kriesel 2020-04-21 04:49

[QUOTE=Uncwilly;541477]Epoch Times is a biased media source. As is Breirbart.[/QUOTE]The chinese undercounting has now been confirmed by the Chinese government's upward revision. That doesn't mean necessarily the new count is accurate either.

kladner 2020-04-21 07:25

[QUOTE=kriesel;543342]The chinese undercounting has now been confirmed by the Chinese government's upward revision. That doesn't mean necessarily the new count is accurate either.[/QUOTE]
The UK will have to do a lot of updating, too, when they start catching up on nursing home deaths. Does that make them deceitful?

xilman 2020-04-21 08:30

[QUOTE=kladner;543347]The UK will have to do a lot of updating, too, when they start catching up on nursing home deaths. Does that make them deceitful?[/QUOTE]In my view, no. The have been quite open in acknowledging that the data is incomplete.

Apply Hanlon's Razor.

Dr Sardonicus 2020-04-21 11:18

[QUOTE=kriesel;543342]The chinese undercounting has now been confirmed by the Chinese government's upward revision. That doesn't mean necessarily the new count is accurate either.[/QUOTE]I posted about an upward revision several days ago, [url=https://www.mersenneforum.org/showpost.php?p=542950&postcount=638]here[/url].


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