Losing Covid-19 antibody immunity after six months after Pfizer vaccine

https://thedaily.case.edu/new-study-nursing-home-residents-health-care-workers-lose-more-than-80-of-their-covid-19-immunity-six-months-after-pfizer-vaccine/

by walterbell • 5 years ago

121 139 5 years ago

thedaily.case.edu

nyokodo• 5 years ago

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...”

bryan04• 5 years ago

True, but this is consistent with several other studies[0..3] which show waning immunity from pfizer in hospitalized patients.

This is why Israel is requiring boosters and the US is following suit.

[0] https://www.medrxiv.org/content/10.1101/2021.08.24.21262423v...

[1] https://www.nature.com/articles/d41586-021-02261-8

[2] https://www.cdc.gov/mmwr/volumes/70/wr/mm7037e2.htm?s_cid=mm...

[3] https://www.medrxiv.org/content/10.1101/2021.08.06.21261707v...

Edit: added more studies outside of Israel

timr4• 5 years ago

The Israel study (not "studies") is an outlier, and is inconsistent with the other studies that have been done so far:

https://nitter.net/mugecevik/status/1430218372348878860?lang...

https://www.nature.com/articles/d41586-021-01557-z

This one in NEJM, from today, just being the latest:

https://nitter.net/davidwdowdy/status/1438268969211744256#m

https://www.nejm.org/doi/full/10.1056/NEJMoa2110345?query=fe...

...which is why, also today, the FDA recommended against boosters for healthy adults:

https://www.wsj.com/articles/fda-says-covid-19-vaccines-rema...

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.

MuffinFlavored• 5 years ago

does the booster buy you another 6 months?

jonathanstrange4• 5 years ago

Elderly and at risk people also get booster shots in Germany. My mother is scheduled for one in October.

basicplus2• 5 years ago

a better overview....

https://theconversation.com/declining-antibodies-and-immunit...

daenz2• 5 years ago

Good news for Pfizer shareholders as there will be endless purchase orders from the government, and little incentive to improve its durability

Uehreka• 5 years ago

…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.

chitowneats• 5 years ago

Moderna also announced recently the effectiveness of their vaccine wanes.

https://www.reuters.com/business/healthcare-pharmaceuticals/...

Vecr2• 5 years ago

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.

bryan04• 5 years ago

Some studies[0] have shown Moderna does not have the same waning problems as pfizer, possibly due to pfizer’s much smaller dosage.

https://amp.ft.com/content/aaddc31b-415d-43d0-b314-bc89a8b86...

daenz2• 5 years ago

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?

andreygrehov• 5 years ago

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.

himinlomax• 5 years ago

Is that snark? Do you believe they did this on purpose?

generalizations• 5 years ago

Big corps have been known to do worse...see, e.g., the nesle baby formula scandal.

https://www.ranker.com/list/nestle-baby-formula-boycott/meli...

trhway• 5 years ago

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.

fsh• 5 years ago

COVID-19 is becoming endemic. The second booster will be the virus itself.

encryptluks23• 5 years ago

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.

walterbell9• 5 years ago

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.

mrosett• 5 years ago

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.

walterbell9• 5 years ago

Recent Mayo Clinic study estimated Pfizer was 42% effective against Delta, https://www.medrxiv.org/content/10.1101/2021.08.06.21261707v...

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.

s5300• 5 years ago

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.

https://www.npr.org/2021/07/16/1017002907/u-s-covid-deaths-a...

https://medicalpartnership.usg.edu/covid-19-staggering-stati...

https://www.cnet.com/health/99-of-covid-deaths-are-now-of-un...

https://www.al.com/news/2021/08/99-of-alabamas-2379-covid-de...

https://www.reuters.com/world/europe/italy-says-99-covid-dea...

usrusr• 5 years ago

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.

lamontcg7• 5 years ago

Unvaccinated hospitalization and death rates are roughly 2x higher with delta.

https://www.thelancet.com/journals/lancet/article/PIIS0140-6...

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.

yosito2• 5 years ago

If there is vaccine escape (e.g. Delta) the risk of serious illness or death is that same as an unvaccinated person

Uh, source? As far as I know vaccines still offer significant protection against delta.

walterbell9• 5 years ago

The sentence you are quoting says IF there is escape, it doesn't comment on the likelihood of escape.

Related discussion in sibling thread, https://news.ycombinator.com/item?id=28548083

mrtesthah• 5 years ago

...rather than nasal/mucosal immunity which prevents infection via the upper respiratory system...

Who says?

Expansion of tissue-resident CD8+ T cells and CD4+ Th17 cells in the nasal mucosa following mRNA COVID-19 vaccination:

https://www.biorxiv.org/content/10.1101/2021.05.07.442971v1

If there is vaccine escape (e.g. Delta) ...

The delta variant does not escape vaccines. They are extremely effective at preventing hospitalization even after antibodies have waned.

robertwt7• 5 years ago

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

walterbell9• 5 years ago

Increasing the time period between 1st and 2nd shots can improve effectiveness. This has been done in UK and Canada.

There have been no clinical trials of mixing vaccines, but that hasn't stopped some countries from trying.

If you've previously recovered from Covid, you already have long-lasting immunity.

dboreham2• 5 years ago

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.

rpmisms• 5 years ago

If you've previously recovered from Covid, you already have long-lasting immunity.

Careful, suggesting that can get you crucified in the US.

0xdeadb00f2• 5 years ago

I think it's I'll advised to mix and match vaccines. If you've gotten the first Pfizer, get the second one and nothing else.

It's probably safer to wait it out rather than risk something by mixing vaccines (something I think there is little study on ATM)

creatonez• 5 years ago

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.

throwaway2462• 5 years ago

Ask your doctor instead of HN.

jonathanstrange4• 5 years ago

That's the most reasonable advice I've seen in this thread so far.

walterbell9• 5 years ago

A recent study, "Waning of BNT162b2 vaccine protection against SARS-CoV-2 infection in Qatar", https://www.researchgate.net/profile/Hiam-Chemaitelly/public...

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.

bildung2• 5 years ago

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.

bigodbiel• 5 years ago

And then we return to a case of personal protection over community protection, undermining the case for vaccine mandates.

thehappypm3• 5 years ago

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.

d--b• 5 years ago

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.

occamrazor2• 5 years ago

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.

raducu3• 5 years ago

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.

red_trumpet• 5 years ago

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.

cat_plus_plus• 5 years ago

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.

Kiro3• 5 years ago

Yeah, these professors and researchers are clueless. The true experts are random people on Hacker News.

toyg• 5 years ago

The modern web in a nutshell: "We've had enough of so-called 'experts', we know better!".

ghuin• 5 years ago

If this pandemic has taught us anything is that professors and researchers are as clueless as the average online commenter.

rob742• 5 years ago

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...

Aachen• 5 years ago

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.

raducu3• 5 years ago

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.

marktucker• 5 years ago

Maybe you had a recent exposure?

qwerty456127• 5 years ago

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.

dham• 5 years ago

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.

Saptarishi2• 5 years ago

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?

LurkingPenguin2• 5 years ago

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.

I didn't see any mention in the article about memory T and B cells. The article only mentions antibodies. Where did you see this?

rob742• 5 years ago

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...

GeekyBear• 5 years ago

The people who had the original version of SARS 20 years ago, still have an immune response today. Memory cells work just fine.

https://www.nature.com/articles/d41586-021-02260-9

When you encounter the virus again, those with a healthy immune system will ramp up antibody production.

kjaftaedi• 5 years ago

the memory cells do not retain this knowledge for extended periods of time in the case of the current Covid vaccines we have

This is a very misinformed statement as this data hasn't been collected yet.

rjzzleep• 5 years ago

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.

[1] https://en.wikipedia.org/wiki/Adaptive_immune_system

david_draco• 5 years ago

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.

tibbydudeza• 5 years ago

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.

logifail5• 5 years ago

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.

Oh, and maybe we all need to take another look at the CDC's 'Leading causes of death' chart. Plenty of ways to die other than Covid19: https://www.cdc.gov/nchs/fastats/leading-causes-of-death.htm

The idea of reaching 'zero Covid' is dead (if it was ever much of a proposition anyway).

[0]https://www.spiegel.de/panorama/corona-mindestens-26-neuinfe...

bsaul4• 5 years ago

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.

morsch• 5 years ago

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.

https://www.gov.uk/government/publications/spi-m-o-consensus...

logifail5• 5 years ago

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?

https://www.forbes.com/sites/niallmccarthy/2020/03/12/the-co...

native_samples• 5 years ago

The SPI-M models have a consistent history of being wildly wrong everywhere they've been applied. It's really not worth paying any attention to them.

1shooner• 5 years ago

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.

smaryjerry• 5 years ago

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.

logifail5• 5 years ago

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]

[0] https://www.bbc.co.uk/news/uk-58030125 [1] https://www.mirror.co.uk/news/uk-news/more-half-covid-patien...

lamontcg7• 5 years ago

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.

logifail5• 5 years ago

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?

[0] https://www.wa.de/nordrhein-westfalen/muenster-2g-party-coro...

Losing Covid-19 antibody immunity after six months after Pfizer vaccine

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