> they looked at humoral immunity—also called antibody-mediated immunity—to measure the body’s defenses against the coronavirus.
The title is misleading. Humoral immunity is not the only aspect of immunity but it was the only aspect measured. Cellular immunity is generally much longer lived than antibodies. The title should be something like “losing 80% of Covid-19 antibodies after 6 months...”
We'll see where this goes after ACIP, but this is now highly politicized, and the recommendation of boosters for healthy adults is far from a sure thing.
The nejm study you reference is great, but it only goes up to 6 months! We want to look at waning in the 6-9+ month period to see if boosters are needed.
> There have been several studies demonstrating waning inline with Israel’s data:
You cite three links: the first is self-reported data, which is problematic. Nevertheless, it still finds effectiveness against infection of 74%. This is a bit lower than the other studies (consensus is around 80%), but not dramatically so. If anything, it is evidence that the vaccines remain effective against the most challenging endpoint (infection), with only minor declines in effectiveness that might just as easily be statistical noise.
The second is a news article, referencing the Israeli study. It is not "a study". It is not new information.
The third is the Mayo clinic study (covered in the Twitter thread from Muge Cevik) and explicitly says that vaccinations remain highly effective against infection and hospitalization over the study period, and tries to extrapolate from a fluctuation in infection data in the final month of the study. This is sketchy:
> Both vaccines were highly effective during this study period against SARS-CoV-2 infection (mRNA-1273: 86%, 95%CI: 81-90.6%; BNT162b2: 76%, 95%CI: 69-81%) and COVID-19 associated hospitalization (mRNA-1273: 91.6%, 95% CI: 81-97%; BNT162b2: 85%, 95% CI: 73-93%). However, in July, the effectiveness against infection was considerably lower for mRNA-1273 (76%, 95% CI: 58-87%) with an even more pronounced reduction in effectiveness for BNT162b2 (42%, 95% CI: 13-62%).
Again, this claim is an outlier. When you have an outlier based on questionable methodology, you must be skeptical of the claim.
> The nejm study you reference is great, but it only goes up to 6 months! We want to look at waning in the 6-9+ month period to see if boosters are needed.
The NEJM is just the latest study, not the only study. Also, the two studies that vex you so -- both the Israeli and the Mayo clinic study -- occurred within six months of their vaccination programs.
Essentially, you're projecting doom based on two studies that disagree with the ~dozen others that have been conducted, that have methodological problems, and are inconsistent with known biology. When given evidence to the contrary, you dismiss it, in favor of speculation about what might happen tomorrow. You're latching on to outliers which confirm your biases.
Ok let me be clear here. I am not intending to project doom, what I am trying to project is that there is real data which shows boosters are beneficial.
Of course the vaccines even without boosters are clearly extremely effective. Even as breakthrough cases increase because of waning immunity, the prognosis for someone fully vaccinated is very different compared to someone who is unvaccinated.
The main thing I disagree with you with, and would use your argument against you, is that there clearly is real data showing waning effectiveness and the benefit of boosters. The main argument for not recommending them is that the vaccines would be better off for people that have not been vaccinated in the first place. Well no shit, but if that population is refusing to take them then the point is moot.
The Mayo clinic study is the other major outlier. The Mayo clinic study found that the vaccines were highly effective, but nonetheless tried to extrapolate from a trend seen in a subset of the data from the final month:
> Both vaccines were highly effective during this study period against SARS-CoV-2 infection (mRNA-1273: 86%, 95%CI: 81-90.6%; BNT162b2: 76%, 95%CI: 69-81%) and COVID-19 associated hospitalization (mRNA-1273: 91.6%, 95% CI: 81-97%; BNT162b2: 85%, 95% CI: 73-93%). However, in July, the effectiveness against infection was considerably lower for mRNA-1273 (76%, 95% CI: 58-87%) with an even more pronounced reduction in effectiveness for BNT162b2 (42%, 95% CI: 13-62%).
There are many problems with this, and it shouldn't be given much weight.
Since covid 19 is new. No one really knows how much time a booster can give or if it'll be similar to flu when each year there will be a need to a shot relevant for this year variants.
What so far seems reliable enough is that the vaccination itself reduce chance for complications when you do get it.
Not enough time has elapsed to say, but it certainly does appear to put immunity back up to original levels, which were against wild-type, even though delta is worst.
>that maybe it was always going to take 3 shots with Covid
Why does it feel like that there is constant retconning going on when it comes to these Covid vaccines? Have we truly always been at war with Eastasia?
Completely wild speculation, but I think it will be more than 6 months, because covid variance is much less than flu.
There is emerging proof that dissease+vaccine immunity is much better than dissease or vaccine alone, but it might also be the booster effect.
After all, there are other vaccines -- such as hepatitis B where you need a booster after one year (booster 3), before you get your long-lasting antibodies.
There appears to be complete lack of clarity in what we're aiming to achieve. As in asking ourselves "what are the next steps?" as my OH is wont to say.
At several points in 2020 it seemed fairly clear that health services were at risk of being overwhelmed. That's a pretty big deal, drastic measures to try and prevent that seemed the appropriate and necessary response.
Now that a majority of adults are vaccinated - and hopefully almost all of the most vulnerable - are we still at risk of health services being overwhelmed?
If the vaccines are keeping a majority from serious illness from a Covid19 infection, where are the patients coming from to overwhelm the hospitals?
It's also become completely clear that the delta variant can (and will) both a) infect and b) spread in the vaccinated population. Happily the vaccine does a good job preventing serious illness, so these people aren't likely to end up in hospital.
In Münster, Germany 380 vaccinated people attended a party in a nightclub on 3 September, the latest data show 81 confirmed Covid19 infections from this event.[0] This event is being reported as if it were somehow a failure or a scandal, but isn't this how mass vaccination is supposed to work? The cases are all mild. Nothing to see here, move along...
At some point we're going to have to stop testing, stop contact tracing, but keep offering vaccines(!), although stop stressing about who choses to take them, and head back to how we dealt with viruses before 2019.
I’ve been waiting for governments to reach that conclusion for months now. Alas, it seems that today’s political speech are voluntarily simplified to the extreme, probably as a mean to maximize the expected result (aka: getting the max number of people vaccinated).
The risk being to antagonize educated citizen that may completely loose respect for public policies as a consequence.
The question of whether hospitals are overwhelmed is actually multi-factor. Are some hospitals overwhelmed? Yes, but is the cause due to COVID or unvaccinated patients? The fact is there is a labor shortage right now, many people are struggling to hire and find people and at my local hospital the rooms are there, built, empty but they cannot be maintained or used because the nurses have all quit because of the ease to find another job, high stress, risk of catching COVID, mask requirements all day, dealing with people who won’t wear masks and more issues that are all directly related to the disease but not caused by the disease itself. Now they can find a less stressful job, maybe working remotely from home, move to a cheaper cost of living area, or simply work in an environment without masking all day long. When Delta hit nurses quit because they didn’t want to deal with it any more.
> Yes, but is the cause due to COVID or unvaccinated patients?
Given hospitals routinely test for Covid on admission, isn't there a third option? Patients admitted to hospital with non-Covid19 medical issues who then happen to test positive and subsequently get put in the statistics in a total which the media then report as "Covid19 patients in hospital"
See:
"23% of Covid infections in hospital [in the UK] - or nearly one in four - were patients admitted for other reasons"[0]
"More than half of Covid patients in hospital [in the UK] 'tested positive after admission'"[1]
Now that a majority of adults are vaccinated - and hopefully almost all of the most vulnerable - are we still at risk of health services being overwhelmed?
Maybe? The official model for the UK projects (it stresses that it's not a prediction, they're not very confident) 2000 daily hospitalisations in a likely, optimistic scenario. I don't know how many hospitalisations it takes to overwhelm the system in the UK.
The numbers per capita are bound to be worse in Germany and parts the USA, which have lower overall vaccination rates. An astonishing 15% of the population over 60 in Germany is still not vaccinated. Younger people end up in critical care in much lower numbers, but those that do, tend to stay there for a longer time.
> The numbers per capita are bound to be worse in Germany and parts the USA, which have lower overall vaccination rates
Germany and the USA have way more critical care beds available per capita than almost anywhere else in the developed world, by some margin, at least based on the figures in this article (the US more than 5x as many as the UK, Germany almost 4.5x)
To a dreadful first-order approximation, shouldn't it be around 5x harder to overwhelm a system which has 5x more capacity?
> To a dreadful first-order approximation, shouldn't it be around 5x harder to overwhelm a system which has 5x more capacity?
Not with an exponentially spreading disease. Remember the lake that double its size each day, and becomes full in 50 days: it takes 49 days to make it half-full, and if you doubled its capacity, it'd fill in 51 days instead.
In the end, it mainly depends on the (serious) morbidity rate and the transmission rate. The latter more than the former, generally: if it is any higher than one, you'll have a doubling period just like the lake (longer than a day, though) until you approach saturation (a sizeable portion of the population is infected or immune). Doubling hospital capacity will only give you a doubling period's worth of time before you have to resort to other measures that push the transmission rate below 1.
Now if the (serious) morbidity rate is so low that hospitals don't become saturated even as most of the population got infected, that's another story.
> Not with an exponentially spreading disease [..] remember the lake [...]
Mathemetically that's OK but cases can't just keep on doubling, we'll run out of uninfected people and/or ones vulnerable enough to get a Covid19 infection that puts them in hospital.
As a thought experiment, if tomorrow we were to magically vaccinate in one fell swoop all the under 18 year olds in Germany (or the UK, or the USA), just how many intensive/critical care hospital beds would that prevent from being filled up by those very same under 18 year olds over the coming winter?
Note that at the start of this month (September) the BMJ reported that "80% of young adults in UK are likely to [already] have antibodies"[0]
>If the vaccines are keeping a majority from serious illness from a Covid19 infection, where are the patients coming from to overwhelm the hospitals?
In my part of the world (US south), they are coming from the half of the population that refuses to be vaccinated. They are still overwhelming the ICUs and EDs. Non-essential procedures for the rest of us have been rescheduled etc. It's just another wave, who knows how many more we'll have?
So from where we're at, any decrease in immunity still presents enough of a threat to the healthcare infrastructure. Lung cancer and heart disease aren't shutting down other units of our hospitals so they can move nursing staff to ICU.
> It's also become completely clear that the delta variant can (and will) both a) infect and b) spread in the vaccinated population.
It isn't clear at all that delta breakthrough infections result in superspreading. There are documented cases of transmission chains of breakthrough infections, but I haven't seen any instances of single individuals with breakthrough infections creating superspreading events. By preventing the worst symptoms and reducing the amount of viable virus and duration of breakthrough infections, transmission is almost certainly reduced by some amount. It may be a substantial amount. Literally nobody knows. People are assuming that since transmission isn't reduced to zero that we have to assume it isn't reduced at all, which is almost certainly false.
> It isn't clear at all that delta breakthrough infections result in superspreading.
The party in Münster that's making headlines over here is being called a superspreading event.[0] The number of confirmed infections has now risen to 83.
> transmission is almost certainly reduced by some amount. It may be a substantial amount. Literally nobody knows
If no-one knows, is the phrase "almost certain" appropriate?
We know for certain that the disease course in breakthrough infections is shorter and milder. Yes, it is almost certain that transmission would be reduced.
And the Münster party doesn't have adequate contact tracing at all. That could be one unvaccinated person with forged or lacking credentials that infected everyone else. They don't know who the index case or index cases were. At least 28 of the affected people haven't submitted proof of vaccination, and if the person who caused the outbreak knew they were breaking rules and got sick they may have avoided getting tested and might not even be in the 83 known cases.
Aren’t anti bodies supposed to get down at some point? I thought the point was that the immune system would make new ones a lot faster cause it already had to build them once.
Yes, but the response will be slower than if you still have a large amount of antibodies already there.
How much difference does it make in practice is still being researched, and the uncertainty is the cause of the conflicting recommendations for or against boosters.
High antibody titers is one reason it's very unlikely to get reinfected within 3 months.
But it's more complicated as there are multiple antibody types -- the actual infection produces antibodies in your nose that aren't produced when you get the vaccine, so those antibodies would protect even more.
I read that there are ongoing studies to administer covid vaccines intranasally to protect even better (I miiight have just reas that they were actually using one of the mRNA vaccines in existence but just putting it in your nose)
edit: I could not find the story about an existing mRNA vaccine being tested intranasally, but there are other vaccines in development that are given intranasally.
> and the uncertainty is the cause of the conflicting recommendations for or against boosters.
Imo it's more relevant that the majority of the human race is not even vaccinated twice. We have to decide, where we can safe more lives. Boosting the immune response in western countries, or giving vaccine to the poorer parts of the world.
> As of August 22, 2021, it is estimated that just over 80% of persons ≥12 years of age have received both doses of these mRNA vaccines. This appears to be the highest mRNA vaccine coverage worldwide ... Qatar has unusually young, diverse demographics, in that only 9% of its residents are ≥50 years of age, and 89% are expatriates from over 150 countries.
> ... BNT162b2-induced protection against infection appears to peak in the first five weeks after the second dose, but then gradually wanes month by month, before reaching diminished levels by the 20th week. Meanwhile, BNT162b2-induced protection against hospitalization and death appears to persist with hardly any waning for at least six months following the second dose.
The graph on page 25 reports that effectiveness of Pfizer against symptomatic infection falls to 0.0% after the 20th week.
The important part of your quote: "Meanwhile, BNT162b2-induced protection against hospitalization and death appears to persist with hardly any waning for at least six months following the second dose."
The vaccine reducing Covid symptoms to that of the common cold is a perfectly fine outcome IMO.
All viruses are like this. The first time a new mechanism originates, it decimates the population because nobody's immune systems have any protection of any kind whatsoever. That's how you get a New York scenario -- everyone exposed gets infected, very few people have natural immunity. Hospitals explode.
Fast forward 2 years. Many many people have had Covid and many many people have been immunized. Even if you get exposed a year later, the immune system has at least some idea of how to handle it. You get sick, but your immune system can fight it off. For a little while your immune system will completely annihilate any virus that it encounters, but after a while it chills out.
The initial anti-body levels produced by Biontech are ridiculously high, something in the 10,000s, while other vaccines produce 1000 or 100. Any value above a few dozen or so is good.
So 20% of 10,000 after six months is not really worrisome.
Since non-sterilizing, intramuscular vaccines provide blood/serum antibodies that offer protection against serious illness/death, rather than nasal/mucosal immunity which prevents infection via the upper respiratory system, recipients of existing Covid vaccines can be infected. If the vaccine works, they will be protected from serious illness. If there is vaccine escape (e.g. Delta) the risk of serious illness or death is that same as an unvaccinated person, i.e. a few percentage points.
After recovery from their Covid infection, they will have long-lasting immunity from infection, transmission and serious illness, with no further need of intramuscular vaccines or boosters. To shorten the duration of infection, accelerate recovery and reduce the risk of long-term side effects, a variety of early treatments are available, including monoclonal antibodies. Early treatment is especially important for those with other medical complications.
In the EU, recovery from Covid (proved via antibody test) enables qualification for the EU health pass, including travel to/in EU. At present, that duration is limited (as are vaccines), but that will hopefully change as more data becomes available from ongoing studies of both natural and artificial immunity.
My understanding is that there's little evidence that patients (vaccinated or unvaccinated) have worse outcomes with delta; they're just more likely to spread it.
> However, in July, the effectiveness against infection was considerably lower for [Moderna] mRNA-1273 (76%, 95% CI: 58-87%) with an even more pronounced reduction in effectiveness for [Pfizer] BNT162b2 (42%, 95% CI: 13-62%). Notably, the Delta variant prevalence in Minnesota increased from 0.7% in May to over 70% in July whereas the Alpha variant prevalence decreased from 85% to 13% over the same time period.
> there's little evidence that patients (vaccinated or unvaccinated) have worse outcomes with delta; they're just more likely to spread it
Entirely possible, as viruses historically evolve to be weaker and more transmissible. That would be good news.
Many other studies disagree with that one. Current consensus is that the Pfizer vaccine is well over 90% effective against severe disease from Delta, and over 80% for infection:
That sentence is extremely misleading. The study showed people losing more than 80% of their antibody immunity. But they also have T-cell and B-cell immunity which lasts longer.
Here's a third study, from Qatar, based on positive PCR tests in recipients of Pfizer vaccines, which estimated 0% (not a typo) vaccine effectiveness against symptomatic infection after 20 weeks, https://news.ycombinator.com/item?id=28548322
It seems like a broken record but you don't need active antibodies to have protection from the vaccine. Antibodies give you protection in that moment. If you have no antibodies, you are extremely likely to test positive because the virus -- temporarily -- can freely enter your cells and replicate. However, other immune system components quickly identify the invader, re-boost antibodies, and crush the infection.
Expecting the vaccine to produce high antibody counts for life is not how our immune systems work.
>...estimated 0% (not a typo) vaccine effectiveness against symptomatic infection after 20 weeks
That's also extremely misleading. The greatest vaccine benefit is not elimination of merely symptomatic infection, but to reduce serious symptoms (i.e. hospitalization) and death.
Here's what the study says about that:
Meanwhile, BNT162b2-induced protection against hospitalization and death appears to persist with hardly any waning for at least six months following the second dose.
It's good that the CDC updated their definition of vaccine to make it clear to the general population that non-sterilizing Covid vaccines provide "protection" and not "immunity", to reset the expectations of vaccine recipients who may have believed that Covid vaccination provided immunity or stopped transmission.
It’s unfortunate however that public policies in most western countries haven’t adapted to that fact yet (which has been a serious hypothesis since the beginning). they still encourage risk-free patients to get vaccinated in the hope of herd immunity. It’s just sad.
That's interesting. If that bears out, it suggests without antibody immunity people will get infected by COVID. However, that same study also shows that the vaccine still prevents serious illness and death, i.e. those other immunity mechanisms are still there and effective, just not kicking in quickly enough to block infection. So "lose more than 80% of their COVID-19 immunity" is still misleading.
Transmissibility and virulence tend to be linked via in-host replication rate (viral load). It isn't quite that simple since if the virus can better evade in-host immune responses then higher viral loads could be better tolerated by the host, but generally transmissibility and virulence are expected to move together. It isn't clear that D614G or B.1.1.7/Alpha involved enhancements in virulence, but delta's advantage in transmission over Alpha does seem to come from increased viral loads, which causes more severe symptoms.
And even the difference seems to be about the same for both groups, which I read as a sign that delta is just better adapted to the upper respiratory tract where immunity from intramuscular vaccines generally doesn't happen. It seems to be a completely separate immune system (this part is not crude layman's speculation but crude layman's rewording of established knowledge I think) which is also consistent with the recorded observation that patients who struggled for their lives typically lost much of their infectivity long before the struggle even started to get serious. In a fully vaccinated environment it might not be so bad to get the "other immune system" to know the virus before the one prepared by intramuscular lowers alert status.
There's no "other immune system" involved. With RNA viruses in particular there's a long phase where infected cells are pumping out viral debris rather than correctly packaged and infectious virions. With severely ill people the cells pumping out viral debris late in the disease cause the same immune response to those proteins just like "live" virus. They aren't infectious though.
This is why a long time ago back in like April 2020 there were reports of "lingering infections" up to 90 days long in South Korea when measured by RT-PCR at high cycle thresholds.
This is probably why Christiano Ronaldo was testing positive for COVID long after he was recovered and (in)famously called PCR testing "bullshit".
With breakthrough infections it is also seen that while the Ct values are comparable between breakthrough infections and unvaccinated infections, the breakthrough infections have less culturable virus and decline faster -- the PCR machine is reading more viral debris.
Also, this is why the whole issue of hospitalized patients being moved back into nursing homes in NYC early in the pandemic is non-issue since they weren't infectious (and the peak in nursing home deaths occurred before the peak in returning patients to nursing homes). Cuomo is still a sexually harassing asshole though.
There's theories that some long COVID cases might be due to lingering viral debris being pumped out by cells, and might be why some vaccine recipients feel relief from symptoms. Although I think its looking more like long-COVID/PASC has more to with autoantibodies.
I think I may be reading/interpreting your comment incorrectly after writing this/digging up these sources -
Whether or not Delta specifically is causing a larger impact on severity of outcomes, we know for a fact that it's more transmissible. And unvaxxed are quite literally dying 99:1 against vaxxed now - mostly from delta. Even if it's less likely to kill/cause severe irreversible organ damage per case, it seems somewhat safe to say the vast majority of unvaxxed are going to get it sooner than later at this point because of increased transmissibility - which will lead to a giant pile of bodies that didn't need to happen.
I would like to think that info alone probably indicates that delta is having a larger affect on the severity of outcomes, but I know there's more to statistical analysis than that. Anyways.
…wouldn’t they just seek out a vaccine manufacturer whose vaccine has better longevity? Idk if this applies to Moderna, but even if it did, at this stage in the game there are over a dozen vaccines in production worldwide.
Are you suggesting that the likelihood of a contract renewal worth tens of billions of taxpayer dollars rests solely on our government seeking to objectively determine the best vaccine for the taxpayers?
Not in the near future. Pretty sure there are multi-year contracts given that the US government was able to negotiate the Pfizer vaccine price from $30+ down to $19.50 per dose.
I don't think any of them have better durability. If you used the Biothrax reduced schedule of doses at 0 months, one month, 6 months (five months after second dose), 12 months (six months after third dose), and 18 months, you might be able to switch to boosting once a year before a predicted spike. That would be improbable even in the richest countries (look at how Anthrax went in the US military), so the probable solution would be not to care about infection, or to pray to the god of live attenuated nasal spray vaccines to save us all.
Maybe they should give you the live virus after receiving the vaccine? I mean, studies show that being vaccinated and getting COVID-19 provides the best immunity.
One of Germany's top health officials actually said that he hopes to get infected with the virus as long as the vaccine protects him from severe symptoms. That caused a bit of a stir in his fan base.
It looks like they on purpose not developing new vaccine for delta, gamma, etc. and instead continue to milk the old one.
Typical MBA myopia - they don't see that with the quick production mRNA tech and the regularly emerging virus variants (seasonal Covid, flu and whatever is to come) they have on hands the perfect business model of vaccine as basically a subscription service, and instead they go the old way of regulatory capture to maximize the ROI of the current product through the vaccine mandate/etc.
That's not 100% true; boosters for the flu do not need to go through the whole 6-month-testing double-blind rigamarole. A COVID booster with a tweaked Delta specific formula could be approved much more quickly than the original vaccine. There's precedent for that.
There's no evidence that boosters actually need to be tweaked for delta.
Boosters produce much broader neutralizing activity, including neutralizing antibodies that are effective (in vitro) against SARS-1 and MERS.
The immune system is designed to be a fuzzy matcher, and the boosters seem to kick broad production of antibodies into gear.
If possible explanations involving the evolutionary psychology of the immune system appeal to you (yes i'm a bit sarcastic there) then it appears that broad immunity is expensive to the immune system, and if you only encounter a virus once then you get a narrower immune response under the assumption that it may be a one-time-thing. But if you get hit with two bad infections in the same year (with sufficient separation between them) your immune system gets the message that you're going to be seeing a lot more of this virus in the future so it goes all "okay, fuck you and your entire family" on the virus.
A couple of years ago (in the year after the swine flu craze), I was at the doctor's to get my yearly seasonal flu shot when I read the label on the vaccine vial stating that it was a seasonal flu / swine flu compound mix. Apparently the manufacturer got rid of their leftovers from the previous year by the help of a cost efficient second cycle use. I doubt that many people, who got their seasonal flu shot that year, were told what else they were injected with.
It was all over the news that the 2009 flu shot would have a swine flu component, and if I recall correctly it was somewhat delayed. I got mine as soon as I could. People who caught it over the summer said it really kicked their ass, the vaccine just made me a bit achey all over for a day.
It makes sense that antibodies are discarded when they are not needed as the human body is rather efficient in that way.
Memory T and B cells are there for a reason.
Sure response time to an infection will be slightly longer but it will be way faster than finding a matching antibody the traditional way when the damage has been already done to your lungs.
Hmm I just got my first shot 2 weeks ago. What would the government and medical experts suggest then? Should we take Moderna instead? I don't see them studying any other vaccine, why?
After spending almost 2 years in lockdown we're just confused what to do if even vaccine status is like this
So true... since the vaccines are so effective, shouldn't they be giving you the live virus after getting vaccinated to help boost immunity? Or are they afraid the vaccines aren't even that effective?
That makes sense. Like, people wear bulletproof vests without having their coworkers shoot them a couple times to make sure the vest works. The best way to avoid gunshot wounds is to not get shot.
>The best way to avoid gunshot wounds is to not get shot.
Bad analogy. What happens is that we're shooting people with .22LR (spike protein inducing mRNA) hoping it will help building immunity to bigger calibers (Covid19, not even talking about the variants).
Because there is a difference between getting actual Covid and getting vaccinated the weakened live stuff. You are just guessing the effect of the latter.
Although I've heard this frequently here, it's not consistent with the many stories from friends detailing reinfection cases. Although friends can be mistaken or fibbing, the sheer volume of these stories along with the specific details of positive tests and so on make me wonder who's correct.
Vaccines and antibodies are not a magical invisible condom that prevent you from getting re-infected again.
They prevent you from 1) having severe side effects, and 2) spreading it to others as much as if you had not encountered either.
No self-respecting immunologist would claim the COVID vaccines prevented re-infection. That's never been the claim outside of those who are ill-informed.
It really seems to me the poster is writing about post natural infection reinfection: the parent poster wrote, «If you've previously recovered from Covid».
1. If you've previously recovered from Covid you have long term immunity.
and
2. Many many stories 1st and 2nd hand detailing reinfection (with symptoms) -- people who have definitively been infected at least twice, symptomatically.
I don't think both 1 and 2 can be true, unless "long term immunity" means something different than my layperson interpretation.
SARS-COV-2 is not one-size-fits-all virus. It rewrites itself frequently and can affect two people with similar pre-existing conditions entirely differently. This is the main cause of misinformation and hysteria vs. e.g. the common cold, which has relatively well-understood and deterministic symptoms.
So in theory, both could be true, and also neither. We simply don't have enough data to say definitively how it really works long term, so any speculation is just that - speculation.
What medical experts can do is be realistic about what to expect from vaccines, recovery, herd immunity, etc. - which they've done quite well. It's other forms of media, "fake" experts, etc. that bolt on more guarantees to vaccines that cause an uproar when they are broken, the biggest one being that vaccines prevent re-infection.
The thing I've noticed the most throughout this pandemic is that people are incredibly short sighted. Explaining how vaccines work, and how they help to prevent spread and variant breakthrough in communities, collectively, is something that people can't seem to accept. They're too concerned with "well it doesn't affect me, so why bother?" without realizing that by getting vaccine they help to end the pandemic sooner, which does impact them directly.
Everyone is tired of the pandemic - medical staff especially - and people not getting vaccinated despite having pretty strong data right now that there are minimal-to-no side effects in the general case is ultimately prolonging the pandemic since new variants keep emerging from mutations in, presumably, unvaccinated individuals spreading shit around.
It's an interesting matter. Numbers should be seen. I have not followed the data, but a quick search reveals a few articles are available, for example:
Reinfection Rates among Patients who Previously Tested Positive for COVID-19: a Retrospective Cohort Study [Mar 2021]
> Of 150,325 patients, 8,845 (5.9%) tested positive and 141,480 (94.1%) tested negative prior to August 30. 1,278 (14.4%) of the positive patients were retested after 90 days, and 62 had possible reinfection. Of those, 31 (50%) were symptomatic. Of those with initial negative testing, 5,449 (3.9%) were subsequently positive and 3,191 of those (58.5%) were symptomatic. Protection offered from prior infection was 81.8% (95% confidence interval 76.6 to 85.8), and against symptomatic infection was 84.5% (95% confidence interval 77.9 to 89.1). This protection increased over time
The literature should be checked to see the different estimates of different researches.
--
Edit: those results seem consistent with my second in queue article,
Reduced Risk of Reinfection with SARS-CoV-2 After COVID-19 Vaccination — Kentucky, May–June 2021
> being unvaccinated was associated with 2.34 times the odds of reinfection compared with being fully vaccinated
Those studies show a good amount of post infection protection, though lower than some relevant vaccines. Also duration of the protection should be factored in, and the consideration is ongoing: only a few hours ago I read material (an Axios summary) about Pfizer vs Moderna,
Ok. If you formulate it those ways, you make it seem as if the vaccine does not make you develop antibodies (as if 'antibodies' implied 'not vaccine') :)
There is enough preliminary evidence to say mixing vaccine types is likely fine. Most of the mRNA vaccines are very similar formulations. I'm expecting it will eventually become recommended whenever it's the most convenient option.
I've looked into this more and you are correct. In fact, I've heard that a newer recommendation is to do the full course of one vaccine, then do another shot of a different one as a "booster".
I wouldn’t be surprised if regular doctors are less informed on latest studies than some information-hoarding member of this forum.
Chances are your doctor will only repeat the general advices given by state medical authorities, which are themselves probably heavily influenced by the sanitary policy of the day (which can themselves be heavily polluted by purely political considerations, depending on where you live)
The difference is that regular doctors understand in relatively detailed ways how the human body works, something most commenters on social networks have no clue about. Moreover, they meet patients who cherry-pick studies and medical information with extreme bias daily in their practice (thanks to "Dr. Google"), which together with knowledge of statistics and the ability to actually understand the studies gives them an exceptionally reasonable perspective on new studies in shifting medical domains and how to deal with them.
I very much hope that my doctor repeats the advice of state medical authorities. In my country, the Covid pandemic has been handled excellently, despite having a comparatively underfunded and not too well-outfitted health system.
i’ve had the personal experience of knowing obviously more about a disease than the specialist i was seing (over minor details, but still). It was surprising to realize how much a bit of googling on a very specific subject can get you, provided you have some general scientific background..
Out of curiosity: what country are you living in ?
I agree and have no doubt that a patient can on occasion know more than a regular medical doctor by googling. Like in any discipline, it's easy for laypersons to get some rather detailed, though often still superficial knowledge about some topics. But in my experience they always lack some depth of knowledge, the necessary background, and very often have the wrong perspective.
Jesus, that's not how immunity works. Your blood is not full of antibodies for every bug you encountered in your lifetime. Mechanisms like memory cells retain knowledge of how to quickly ramp up production if the pathogen is encountered again. They even pre-mutate to anticipate future variants so immunity can get better over time.
I think the point is, the memory cells do not retain this knowledge for extended periods of time in the case of the current Covid vaccines we have. So should we be looking for a 3rd dose, or try to fund a different vaccine?
Well, that's the question that this study doesn't answer. They (of course) didn't try to infect seniors with reduced antibody response with Covid, they only studied the antibody response in the lab. So the memory cells probably weren't a factor in the lab tests...
When you get infected (or vaccinated), your body produces antibodies as part of its primary response. The antibody tests that are commonly done for COVID look for these already circulating antibodies.
Upon infection or vaccination, your body will also produce antibody-producing memory cells to help respond more quickly if you are infected in the future. If you want to test for these memory cells, you can't use antibody tests. You have to use specialized tests that look specifically for the memory cell responses.
There are some commercially available tests, such as https://www.t-detect.com/, which looks at the T cell response.
A lot of the commercially available antibody tests will fail to detect a prior infection after just a few months. T-Detect now says that its test can pick up infections that occurred 10 months ago. 10 months is probably not the limit of detection; it's just based on the amount of time T-Detect has been available to the public.
Researchers have found memory T cells that respond to the original SARS-CoV virus 17 years post-infection:
Can any tests distinguish between having a response due to prior infection from having a response due to vaccination?
In the months before I was vaccinated I had on two or three occasions something that felt a bit different from the usual cold/flu/allergies that I get, but was not severe enough to justify trying to get a COVID test. I'm curious if I actually have had COVID or not.
It's like saying "All people run out of edible food (antibodies) within hours of being hungry (exposure to distinct protein)". Well, yes, but we have the ingredients to make them in the fridge (memory cells). Just measuring the amount of cooked food (antibodies) will tell you how much I can eat right now, but I'm not going to starve (get sick) in the absence of the cooked food (antibodies) since I have the tools - raw food (memory cells) in case I get hungry (exposed again).
In the case of this study, they tell us we've run out of cooked food in 6 months. That doesn't tell us whether we'll starve, because we could have hella stores in the pantry and they specifically did not measure any of that.
It does for certain bugs/substances, doesn't it, though?
I checked my tetanus antibodies(actually anti-neurotoxin antibodies) recently and they were 5 times over what's considered adequate and I haven't had (at that point) a booster shot in over 20 years.
I think other countries (maybe England) are going to start recommending tetanus shot every 30 years. It's probably one of the biggest medical misconceptions that everyone has. The shot lasts for a very long time. Also the chance of getting tetanus is so low for the modern human (that doesn't work on a farm). You basically have to step on glass in soil that has cow feces all over it. Also they try to give you the tetanus shot when you have a deep cut even though it's too late at that point.
It's been more than a year since I catched what I believe was light covid and periodical tests show my antibodies count never falls and even grows slightly, keeping on the level slightly above what people get after vaccines.
It wouldn't be the first time research lives in its own little bubble, (dis)proving something different from what the world wanted to know. Here, they looked into X (antibody presence) and people make it into Y (corona protection), so then yeah commenters have remarks.
Edit: I read the paper and it just speaks of humoral immunity. Wikipedia:
> Humoral immunity is the aspect of immunity that is mediated by macromolecules found in extracellular fluids such as secreted antibodies, complement proteins, and certain antimicrobial peptides.
Antibodies I'll get to below. Complement proteins and antimicrobial peptides links go to articles saying they're part of the innate immune system (covid protection is done by the adaptive immune system if I understand it correctly). So antibodies is the relevant part:
> Together with B and T cells, antibodies comprise the most important part of the adaptive immune system. They occur in two forms: one that is attached to a B cell, and the other, a soluble form, that is unattached and found in extracellular fluids such as blood plasma. Initially, all antibodies are of the first form, attached to the surface of a B cell – these are then referred to as B-cell receptors (BCR). After an antigen binds to a BCR, the B cell activates to proliferate and differentiate into either plasma cells, which secrete soluble antibodies with the same paratope, or memory B cells, which survive in the body to enable long-lasting immunity to the antigen.
So B cells (well, some but not all) are responsible for long-term immunity, distinct from antibody levels. An antibody (further up the article) is a Y-shaped cell with receptors on the tips which it uses to bind to and thereby tag pathogens for other parts of the immune system to deal with or to neutralize it directly.
So it doesn't sound to me like the paper talks about how long vaccination has an effect, just how long the Y-shaped receptors are in the blood for. This is the so-manyth research I've seen looking at antibodies rather than memory cells. I'd be curious why, but either way it's an incomplete way of looking at protection.
I doubt that the professors and researchers are clueless, but I'm not so sure about the people writing articles based on this research. And even these people might not be clueless, they might simply be willing to sacrifice accuracy to get a better headline...
Jesus, that's not how immunity works either. The immune system isn't one thing that learns and then works. Certain components of it work like that, but certain others do not.
You can't just throw out vague statements like that and pretend it's the truth and fact. There are innate and adaptive components, but even the adaptive components, which you conveniently threw everything under, aren't as simple and straightforward as you make them out to be.
For a very "basic" introduction to the adaptive immune system the wikipedia article has some reference[1].
Part of the whole ordeal about Covid is that the whole adaptive response is nowhere near as clear cut as you make it out to be and any actual epidemiologist agrees with that.
The title is misleading. Humoral immunity is not the only aspect of immunity but it was the only aspect measured. Cellular immunity is generally much longer lived than antibodies. The title should be something like “losing 80% of Covid-19 antibodies after 6 months...”