Yes, it was already mentioned today in the update to parliament here. Apparently - as with other respiratory viral infections - if you don't get it really bad then you may not be immune. That's a pretty fine line there. This would explain some of the more puzzling positive / negative / positive test sequences.
The LabCorp test is not FDA cleared or approved and is being used under an emergency act.
"Testing was performed using the cobas(R) SARS-CoV-2 test. This test was developed and its performance characteristics determined by LabCorp Laboratories. This test has not been FDA cleared or approved. This test has been authorized by FDA under an Emergency Use Authorization (EUA). This test is only authorized for the duration of time the declaration that circumstances exist justifying the authorization of the emergency use of in vitro diagnostic tests for detection of SARS-CoV-2 virus and/or diagnosis of COVID-19 infection under section 564(b)(1) of the Act, 21 U.S.C. 360bbb-3(b)(1), unless the authorization is terminated or revoked sooner."
"It is possible for this test to give a negative result that is incorrect (false negative) in some people with COVID-19. This means that you could possibly still have COVID-19 even though the test is negative."
Due to this, it's hard to trust test results. It's a best effort and not perfect.
A PCR will generally have around a 99% sensitivity and a 95% specificity. That depends on things like the nasal swab going all the way to the back in a deeply uncomfortable way and if they only get the front of the nasal cavity (with Covid-19 in particular) it might be just a 95% sensitivity.
Antibody tests will generally have a much lower sensitivity but can detect whether you had the virus in the past.
Dr. Fauci said the only thing you can count on are positive test results, so I would assume false positives are much more rare, but I'm not qualified to say. I do think it's safe to discount a negative test result, especially if you also test negative for flu A/B but still have flu like symptoms and difficulty breathing. Hopefully soon, antibody testing will be available and much more accurate.
You beat the infection due to a skirmish between your 'standard' immune system and the virus infected cells. As soon as you get a full-on immune system response there is a change and some more long term effects come into play. Nature tends to be very efficient, engaging an expensive mechanism apparently leads to caching the knowledge so it can be recalled when required, but if the expense outweighs the cost of doing so then it stays on a one-off basis.
The longer you deal with biology the more impressive it all is.
There is the innate immune system, and the adaptive immune system. If I understand correctly pathogen specific antibodies are created by the adaptive immune system, so maybe if the innate deals with the virus quickly the adaptive is not triggered.
If your innate immune system beats it, does that mean you're effectively already "immune" and are unlikely to develop serious COVID-19 disease when you catch the virus again, or was it just luck?
I'm not referring the general concept. I've asked for a source that supported the claim that covid19 patients that "don't get it really bad" have been found to not get immune.
That was straight from a government hearing today here in NL, those usually don't come with conveniently linked sources but at the same time they tend not to have bullshit in them.
These people came out of hospital. I think they have been hit comparatively hard. I guess (!) we see some result of false-positive test results here, together with coinfection with influenca or even the common flu.
Hospital cases are all lower respiratory tract, but even just within that group there is huge variety. It starts from 'under observation' for a day, then goes through needed oxygen for a day or two, to progressively worse symptoms, cytokine storms, intubation, organ failure and finally death, from a couple of different causes, such as lung damage (the vast majority of the cases) or heart failure (1 in 5). It can reverse at any point during that trajectory, and can also go back-and-forth.
And the speed of onset, progression and severity can change dramatically from person to person.
Finally, in many cases of recovery there is apparently lasting damage.
So, young people have way less antibodies. Lots of stats also show people aged 0-19 have barely any test-confirmed infetions compared to older populations. I also read that for the first 7 days, the virus mostly stays in your throat with mild symptoms and only after that it goes to the lungs causing major issues.
Could it be that young people with strong immune systems easily fight the virus away within the first week?
Out of my keister I'd assume young people's innate immune response might often defeat the virus on it's own. By the time the adaptive immune system kicks in the war is over.
Many in NYC were unable to get a test. I was extremely sick mid-march and was unable to get a test because it was before New York started ramping up capacity. NY blood center requires a positive test result before they'll consider you for plasma donation.
Mt Sinai's study also accepts people that did not get tested for covid-19 at the time of infection. They will accept plasma and then test it for antibodies, which has the handy side effect of telling you if you already had covid-19. I'm scheduled to donate there next week.
I work at a publishing company and I have been seeing more researcher interest in this paper recently from 2010 - Zn2+ inhibits coronavirus and arterivirus RNA polymerase activity in vitro and zinc ionophores block the replication of these viruses in cell culture - https://journals.plos.org/plospathogens/article?id=10.1371/j...
Damn. I was thinking just a couple days ago that serum therapy might be a potential treatment avenue. For whatever reason, the plot of a Dragonriders of Pern novel came to mind, and I realized the similarity of the situation to the COVID-19 pandemic, and found myself wondering if the solution there wouldn't be workable here in the real world.
<Spoilers>
In Moreta: Dragonlady of Pern, a viral disease (a flu strain IIRC[1]) jumps from horses to people, and quickly begins spreading. A quarantine is implemented, but too late, and the illness becomes an epidemic. And this is Very Bad, because the dragonriders and everyone else find themselves with people falling ill and dying just in time for Thread to return.[2]
One of the master healers is infected in the line of treating others. Once he recovers, he realizes that his blood can be used to produce a serum to treat others. And so begins the work of producing the serum and logistical problems of getting it everywhere needed fast enough.
One thing we have over the fictional Pernese peoples is that we have a more advanced medical medical establishment that could probably produce a serum quicker and more precisely, with less secondary infection risk. (Although, a brief shortage of blood-work needles wouldn't surprise me.) And while Pernese dragons can teleport, they also tire, whereas our planes and trucks need only refueling, and each does not require a unique psychically-bonded pilot/driver to operate at all -- round-the-clock shift work is possible.
</Spoilers>
And I just realized, I recalled almost all of those details from memory without the aid of Wikipedia. I read that book back in middle school. Damn.
[1] I might be wrong about this detail. I know I am recalling this from an interview that I read, but I might be mis-remebering. The author might have been stating she took inspiration from the 1918 flu pandemic.
[2] If you're unfamiliar with the Dragonriders of Pern books, the general premise is that periodically, "Thread", a hostile organism which eats all organic matter it can reach, falls from the sky. The dragons and their riders protect everyone else by burning the Thread from the sky before it makes landfall.
They're currently working to establish antibody testing, and require potential donors to be at least 14 days from end of symptoms, but they will still accept your contact information and relevant details for later contact.
Assuming this treatment is viable, hospitals should be sending discharged patients home with the website and number to call for donating after recovery. I think most people will not see this or even know about it.
Dr. Peter Hotez has been proposing clinical trials of convalescent serum therapy for several weeks now. If it works it could potentially be used both to treat infected patients, and reduce the risk of infection for healthcare workers.
I don't know if Dr. Hotez is directly involved, but St. Luke's, which is a Houston-based hospital heavily affiliated with BCM/TCH (where Dr. Hotez works), started trialing this in patients a few days ago.
bio undergrad so take w/grain of salt
1. No, because serum does not contain any cells that have the markers of a bloodtype. You're just transferring the antibodies pretty much. When you spin down a blood sample in a centrifuge, the bottom pellet contains blood cells, the supernatant is plasma. From that supernatant, when you get rid of clotting factors, the remainder is just soluble molecules and antibodies.
2. Maybe. Serum can also contain viruses, but I assume the serum will be treated with chemicals to "clean it up" and just isolate antibodies.
No you don't plasma can be used on anyone. Which is one of the benefits, unlike whole blood it's safe to use with any blood type. Can also be stored and stockpiled.
And yes you can get HepC and other viral diseases from it.
Beyond plasma therapy plasma can be purified as well. Which makes it easy to administer. (See Gamma globulin).
I really, really wish there could be a clear answer on at least this one basic thing that one would think (as a layman) to be fairly understood about viruses and immune response: Having had a SARS COVID 2 infection and assuming the virus hasn't mutated in the way that influenza does periodically to keep needing new vaccines, does or does not your body gain bloody immunity for some time after recovery? From everything I've know to date, the absolute normal, standard thing is that yes, being sick with something viral that doesn't cause your death gives you at least a certain period of months or usually years of immunity to it unless it mutates enough to re-attack without being recognized immediately. Is this not correct? For smallpox it applied, for chicken pox it does, for measles it mostly does for many years, likewise for many viruses for which there are vaccines. We even get immunity from the flu once we've had it for at least some months to a year or two. So why would Covid 2 be different?
Short answer: recovering from Covid-19 probably does give immunity, based on all the precedents you mention, but we can't prove it for sure yet because not enough time has elapsed and no sufficiently rigorous studies have been done.
Of course viral antibodies persist for some amount of time, they don't disappear immediately upon clearing the virus. What we don't know is anything about the shape of that persistence. Is it days or weeks or years? Does it decline linearly, or exponentially (as a half-life), or on some other schedule? What kind of variance between people is there? How much does it vary based on all the other factors, like other health and immunological conditions, or re-exposure to the virus? This is all what we don't know yet, but need to before we can make assumptions regarding herd immunity to start lifting lockdowns.
Vincent Racaniello: We have a bunch of emails and correspondence about the use of convalescent sera, and Frank, for example, who's a professor at Misericordia University, said "Why aren't we using antisera from recovered patients to treat infected people?" and we have some email from Ed Niles in a bit, but I want to just say that yesterday the FDA approved this kind of treatment for serious infections on an emergency basis. So if you have a very serious or life-threatening infection you can apply to the FDA for what's called emergency investigational drug application and you can get convalescent serum, which means serum from someone who's recovered from the infection, is checked to make sure there's nothing else -- no other viruses -- in it, and it can be given to you and we know from previous experience with other infections that this can work.
Rich Condit: The idea here is that someone who has recovered from the disease has antibodies to the virus, in this particular case the SARS-CoV-2, and so if you give them intravenously this preparation that has these antibodies in it, presumably that can latch on to virus that's infecting you and those pathogen antibody complexes will be disposed of appropriately in your body. This what's called, comes under the general umbrella of passive immunization, which you're giving antibodies from some other source which will last you for some period of time and it can be up to weeks or months, actually (we've been through this before), as opposed to active immunization where you mount your own.
Racaniello: Rich, you had some correspondence with Ed Niles. Why don't you...
Condit: Yeah, he's obsessed with this. [laughter] Ah.. let me see here, we haven't highlighted this but I'll clip through it. This came to me, I forwarded it to everybody. "I listened to the first part of TWiV today, through the passive transfer comments," passive transfer being what we were just talking about, passive immunization, "It was claimed that passive transfer was first used in Lhasa in 1968. Smallpox docs shouldn't be short-changed in this regard. VIG, which is vaccinia immunoglobilin, was used a decade earlier. I went to a meeting in 2009 where several smallpox docs talked about their experiences trying a host of putative anti-pox drugs and the impact on their patients. One had tears recalling the impact treating sick patients with untested and unproven drugs. I understand the urge to try something, but there are limits."
Condit: Ok. So Ed, as background, worked for BARDA for a while. I forget what the acronym stands for, but it's a government agency that was born out of the...
Alan Dove: I think it was Biodefense Advanced Research and Development Agency, or something like that.
Condit: There you go. And, he, so he saw a lot of grants having to do with smallpox, anti-pox viral drugs and etc, so he's pretty up on this, and the vaccinia immunoglobilin would be part of that. He's referring to the 60's and before when the global smallpox eradication campaign went forward, and one of the things that was used was the vaccinia immunoglobilin. VIG is, was, prepared by two companies under contract with the US government from pooled serum taken from vaccinies, mostly military at this point. We have 100,000 doses in the stockpile. However, 25 doses have been used in some cases to clear vaccination complications. Provides a link to an article which provides some background for the practicalities of preparing and using coronavirus immunoglobilin if we get to that. "It helped remind me of what we were thinking about 15 years ago. Seems like a lifetime. On another note, pooled monoclonal antibodies have proven to be effective against pox viruses in animal models. Unfortunately this is an expensive way to go," and suggest contacting our friend Mike Bershlinsky (sp?) for looking in more detail. He attached an article from an old friend of ours, Rico Wittick (sp?), since deceased. It summarizes the prep and use of vaccinia immunoglobilin over the decades. Ok. So this is like a review. He correctly refers to a handful of reported anecdotal applications of vaccinia immunoglobilin against smallpox. "I don't know that true controlled studies have been done at this point. By 2011 there were none, even with the compassionate uses of vaccinia immunoglobilin ST-246," which is, was, an experimental anti-pox drug, now approved, "and Senovavir. It was never clear which, if any of them had a positive effect. You need controlled trials. In each case the patient cleared and survived. Controlled studies are hard to come by. So I'm not a big fan of VIG, vaccinia immunoglobilin, and if anyone wants an antibody approach to SARS-CoV-2 they may as well go directly to monoclonals and do the right set of studies. Of course this will take time. Alternatively, if you have other tools in the toolbox, maybe a convalescent serum study is warranted. Any volunteers? Keep the faith."
Racaniello: Well, that's exactly what the FDA is doing. They are doing a convalescent antibody study in case, for prevention. The emergency use is not for prevention, it's for very sick people.
Dove: Right.
Racaniello: Because.. So, Brianne, what could go wrong if you gave someone anti... SARS-CoV-2 antibodies?
Brianne Barker: Well, if we are imagining that there are no other viruses and nothing else there, there are some situations where antibodies and antigens can bind together and get sort of stuck in places, like in some cappilaries and some areas of the skin and kidney and lead to something that in class I call a type-3 hypersensitivity reaction, but really it's something called serum sickness or it's kind of similar to farmer's lung that we see in a few different people. So sometimes we can see some issues there where people will make a response to those antibodies that they're getting from other people, because they are technically foreign proteins that you are injecting in to someone.