It seems far more likely to me that both of these phenomena are explained by higher-than-usual false positive and false negative test rates.
If this 30% recovered don't have antibodies, how did they beat the infection?
Does the immune system have some other mechanism to defat a virus?
Or does the antibody production taper off very fast for some people?
Or can the virus just die out by itself somehow?
Source?
Could it be that young people with strong immune systems easily fight the virus away within the first week?
I'm sorry but do you have a source for that? The only place I read this was in nonsensical WhatsApp forwards.
https://www.nybloodcenter.org/donate-blood/convalescent-plas...
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.
———— https://www.mendeley.com/catalogue/a048aadd-e0c3-3870-bf5d-6...
<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.
https://twitter.com/peterhotez/status/1239387184681177090?la...
1. Do you need the same blood type as the donor?
2. Can other infectious diseases spread via an infusion from an infected donor, ie. hiv, hepatitis?
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).
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.
[1] - http://www.microbe.tv/twiv/twiv-594/ (about 23 minutes in to the program)
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.
https://www.wsj.com/articles/questions-about-accuracy-of-cor...
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."
The Quest test is not FDA approved either: https://www.questdiagnostics.com/dms/Documents/covid-19/SARS...
"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.
This would affect death rate calculations
Antibody tests will generally have a much lower sensitivity but can detect whether you had the virus in the past.
The longer you deal with biology the more impressive it all is.
There was a good TWIV podcast talking about this.
So maybe 30% of people have an "innate" system well geared toward defeating this particular virus. Or/and they had a small exposure.
It's like the Trojan horse coming in, and the soldiers, once inside, getting arrested for tax evasion before they can open the gates.
You latched on to the wrong part of my comment, the part that was not novel, and now you are moving the goal posts to pretend that it was about the other part of my comment.
Finally, there are several links in this thread and other threads on HN on the subject pointing to articles supporting the novel claim, which you would have found if you really cared, (such as the comment I replied to) rather than that you are just pretending to keep the standard for evidence on HN to your personal level. I have no particular reason to disbelieve a government official making a claim like that in a parliamentary setting. I am not asking you to believe the claim, merely that I am passing it on with high fidelity.
If you choose not to believe that I am fine with it, but I am not in your pay, have given you ample opportunity to study the matter for yourself, no excuse for laziness in the times of wikipedia and the rest of the web, and yet, here you are pretending you have some kind of high ground and using all kinds of slurs. 'baseless assertion' (which it isn't, I've given you my source), 'random guys' (which I'm not, but you are), 'all kinds of nonsense' (this isn't nonsense), 'wild claim' (this isn't a wild claim at all, it is actually quite expected), 'cower' (see any cowering?).
That's a lot of suggestion that you are doing, all of which is trying to shed a negative light on something that is not controversial at all, merely something that you didn't know about yet. Which means you probably don't know all that much about biology to begin with.
It's ok that you didn't know something. It's not ok to not want to then correct that by studying the subject. That's called being lazy. It's not ok to then go harassing people and doing all kinds of borderline namecalling to attempt to pick a fight about something that isn't controversial at all.
So, the coward is you. Now get off your high horse and take it as read that for many viral infections the degree of infection can be to some degree dependent on the initial viral load and that in turn can be a big factor in the development of symptoms and whether or not you will end up immune. The immune system can deal with infections in an ad-hoc manner without invoking its long term planning or it can adapt and guard itself for re-infection in the future. The exact mechanism of the cost optimization is known which you would have understood if you read that WP article I linked to above.
This is NOT controversial at all in biology circles and does not need the kind of support that you are whining for. It's like claiming water is heavier than oil or the nucleus of an atom being larger than an electron, or use of global variables being a bad practice in software development. Pick your analogy.
The novel claim was that this also applies to COVID-19, and that claim is amply sourced.
https://www.medrxiv.org/content/10.1101/2020.03.24.20042382v...
In case you can't be bothered to read the entire pdf, this is the sentence you would be looking for:
"Stronger antibody response was associated with delayed viral clearance and disease severity."