The paper claims that 1/5 of people experience Long COVID after an infection. Given that approximately everyone has caught COVID by now, this does not track with how rarely I've heard of people with it.
Wikipedia lists much lower numbers on https://en.wikipedia.org/wiki/Long_COVID (6–7% in adults, ~1% in children, less after vaccination.) and seems to use a more liberal definition than this paper, as it mentions "Most people with symptoms at 4 weeks recover by 12 weeks" (while the paper only considers it "long COIVD" if symptoms last past 3 months).
I've found studies (peer reviewed, as far as I can tell) claiming anything from well under 10% to well over 30%.
I won't make a claim to the accuracy of the numbers, but I can offer an example of how long COVID can be undercounted. My daughter was a competitive long distance runner. Months after recovering from the acute symptoms of COVID, her performance numbers were still about 10% down and no amount of training would allow her to reach her previous level of performance. After many visits to doctors and specialists, she was eventually diagnosed with long COVID due to lung damage. She's still very fast by most measures, but in track, the difference between being in the 99th percentile and the 89th percentile is the difference between a top 3 finish and a bottom 3 finish. This basically ended her track career. In our case, if we didn't have hard data tracking her before and after performance levels, we may not have ever noticed a difference. How many people who aren't competitive athletes are walking around with 10% degraded pulmonary function and just didn't notice?
It's a pretty sad reflection of the times that there's a need to create a throwaway account to talk about long COVID symptoms, but this is a good personal anecdote to draw attention to what's likely happening. In my case, I only caught covid once - somepoint last year just before I would've gotten the updated booster. It took me well over a year to stop having acute pulmonary issues, and my lung performance is down year over year (measured during high intensity training) even though I finally feel no differently at baseline than I did before I caught it.
Most people don't exploit the full capacity of their bodies and so would never notice, which is essentially the point OP is making. This disease very likely ravaged the 20% claimed, but the vast majority may never know because they're just never pushing their bodies hard enough.
I mainly created the throwaway because I'm sharing personal medical information and I'd rather not do that with my main account where people know me IRL.
It ought to be possible to test that hypothesis by comparing publicly available race results for the same athletes on the same courses before and after the pandemic relative to the expected age-related performance loss. Anecdotally as an age-group endurance athlete I'm not seeing any big declines in myself and my friends so I'm highly skeptical that 20% were "ravaged". The actual incidence of significant loss of pulmonary function is probably much lower although I have no idea as to the actual number.
If anyone wants to quantify this then Athlinks is a good place to start for race results. Obviously the data is somewhat noisy, like you'd have to throw out the slower finishers who maybe weren't trying hard. But if there's a significant correlation then it ought to show up.
> you'd have to throw out the slower finishers who maybe weren't trying hard. But if there's a significant correlation then it ought to show up.
Poor performers and no shows are exactly the population you’re looking for. To be clear the argument isn’t about a 10% decline across the board among people with long COVID as there’s non cardio pulmonary symptoms like brain fog, loss of smell, and difficulty sleeping.
If 80% of the fit population had COVID, 20% of them had long COVID, and half the people with long COVID had a 10% decline in race performance. That’s something like an overall 0.8% drop of performance assuming nobody dropped out or joined, but again you’re loosing people on both sides who were most impacted. Thus I’d be highly skeptical of finding an actual connection here rather than something else that impacts more people.
A more useful approach is to take a cohort of people who raced in 2019 and track what happened to every single one of them specifically.
This makes sense. I would've been marked as a "no show" because I had to rescind a job offer because of long COVID which lasted a year. From the government's point of view I was just an unremarkable figure prolonging my bout of unemployment when in fact I had a great job offer lined up that went to shit because I got COVID while on my little bit of celebratory vacation
The PVCs, adrenaline dumps, sleeping problems and anxiety/panic were insane! The doctor thought that my hypothalamus was inflamed because of COVID.
I was a highly trained endurance athlete my entire life and covid/long-covid absolutely destroyed all of that, permanently
After 5 years I would happily trade only a 10% performance loss for the days and nights full of nerve damage pain (neuropathy)and what seems to be 30% performance loss
BTW very relevant to your daughter's story:
the first year of long-covid I was absolutely certain I had permanent lung damage and started searching everywhere for solutions
There are two possibilities that might be hopeful for her
The first is that it might not be permanent alveoli damage (which do not regenerate in humans) but rather obstruction from a "hydrogel" that forms during active covid and takes many many months if not years to dissipate entirely
which are simple enzymes, you can buy Natto-Serra on Amazon and very very slowly perhaps over many months it might help her lungs (this is just a guess)
Thank you for the information, and I'm sorry to hear about your struggles.
> The first is that it might not be permanent alveoli damage (which do not regenerate in humans) but rather obstruction from a "hydrogel" that forms during active covid and takes many many months if not years to dissipate entirely
I didn't go into too much detail in my original post, but we think this is likely what happened to my daughter. Post-COVID, she could still go for long durations at 80% but when she pushed her limits, she would hit a wall and start to experience asthma like symptoms along with the feeling like she had mucous in her lungs that she couldn't get out. It took close to 2 years for her to stop experiencing those symptoms, at which point her competitive running peers had passed her by. She's happy to be able to enjoy running again but she did lose out on the competition part.
It takes very severe disability for it not to be brushed off as depression, anxiety, burnout, or blamed on lifestyle.
Additionally, a lot of those numbers are based on earlier strains of COVID, which were much more severe.
I suspect the 1/5 figure is largely true for "has some degree of cardiovascular damage and worsened general health after COVID", but the number of people actually disabled by the condition is much lower.
That said, any loss of ability is a sad thing, and I am incredibly disappointed that we did not introduce any shared indoor space air quality legislation post-pandemic.
And the lipid nanoparticle based Covid prevention shots caused myocarditis in some younger males, so earlier incidence of cardiovascular complications vs. the present (when most people especially younger healthy males are choosing not to take updated boosters) would correlate with that as well.
They did but if you go through the actual studies, the incidence of myocarditis was low, and almost all cases were non-serious, with no measured long-term impacts.
Further, the studies on long COVID incidence in vaccinated vs unvaccinated people suggested that the rates in vaccinated individuals were lower, though iirc it was only by something like a third or half. (among people who were symptomatic, at least, the total protective effect was likely greater)
The one Thai prospective study that I saw on this subject (the only one I ever found which measured biomarkers of heart damage like troponin before and after injection, which is utterly shameful), estimated a rate of heart damage in adolescent males in the range of 1-3%. So even that would be nowhere near enough to reach the 1/5 number.
I got pericarditis bad enough that I thought it was going to kill me but not bad enough to show up in any test. Thankfully the cardiologist accepted my description of what I felt and prescribed me colchicine which worked. I guess it would be called subclinical pericarditis and it would be good to have some stats on how often that happens.
I suspect many people commit the grave sin of mixing data sources to derive percentages, which seems almost impossible not to do in this case. I also strongly suspect that rates of infection (the denominator in question) were inflated to some extent during the pandemic as insurers and hmo were incentivized to detect covid even when it may not have been the primary reason for presenting. There were also disincentives or at least a lack of incentive to detect teratogenic effects of the lipid nanoparticle based preventative, and unfortunately likely personal biases as the preventative was highly politicized. But I’m not thinking about it much deeper than that, so you may be right.
The reported rates might have been inflated compared to what people presented with, but wastewater tracking and excess death measures all suggest that as a whole, infections were severely under-counted, possibly by a factor of up to over 2x.
Majority of the studies on myocarditis after vaccination found very low rates, with close to zero moderate to serious cases, and a full return to baseline of whatever the metrics studied were, I don't remember.
(The same omicron era the media originally claimed was "not as bad as previous variants." Perhaps not in the acute phase, but as we've seen, that's the least of anybody's concerns who track the longterm risks.)
> I am incredibly disappointed that we did not introduce any shared indoor space air quality legislation post-pandemic.
That seems like a tempting thing to lament, and I did too until seeing this recently:
Study finds HEPA purifiers alone may not be enough to reduce viral exposure in schools
This suggests our most reliable protection to date is consistent N95 usage (since present vaccines don't reliably prevent transmission) until next gen vaccines are developed.
There's more to air quality than HEPA filters. In-line far UV sterilisation, ventilation to reduce rebreathing and CO2 levels, and HEPA might not be enough as a single-building intervention, but it would almost definitely change disease spread dynamics if deployed world/nation wide.
Agreed. In fact, even before COVID this was long overdue to be addressed in classrooms etc:
> ventilation to reduce rebreathing and CO2 levels
Unfortunately since that hasn't happened yet, methods like:
> In-line far UV sterilisation
> HEPA
are not effective. It isn't that they don't kill/stop the virus. The problem traces back to the inadequate forced air exchange and distribution which these methods require, and which is often a show stopper when you're talking about retrofitting existing structures without costs becoming insane. At a certain point it's easier to build new with these things in mind (and we absolutely should be taking requirements to do so more seriously).
> might not be enough as a single-building intervention, but it would almost definitely change disease spread dynamics if deployed world/nation wide.
The point of the previously linked study is to demonstrate that "something is better than nothing" reasoning doesn't always apply. We need to go big to see an actual measurable improvement over longer time spans. Otherwise, what's the benefit seen if you delay an average (but inevitable) infection from occurring by X days? There basically is none.
> Otherwise, what's the benefit seen if you delay an average (but inevitable) infection from occurring by X days? There basically is none.
It reduces the R0 factor, which reduces the amount of people that need to be resistant for herd immunity to take place, and which makes it easier for other measures to bring it down further, potentially below 1 where the disease dies out instead of continuing to spread.
If you get a diagnosis at all, it's going to be a catchall for "idk" like fibromyalgia, CFS, allergies or it's filed away as psychosomatic.
There are probably a lot of syndromes caused by latent infections from virii like EBV, various herpes, HPV, etc that don't go properly diagnosed or treated if they can be treated at all.
Also, it's been found that some viral infections retreat to tissues where their detection might be difficult/impossible without biopsy. You saw this with, for example, Ebola, where survivors could test negative for the virus, but it would still survive and replicate in different isolated tissues like those in the eye.
After covid I suffered from intermittent brain fog for years and also felt like my heart was maybe struggling more than usual when I was training at the gym.
Never enough to warrant going to a doctor unless I was being super paranoid (and spend a long time convincing them I wasn't paranoid) but just enough to always wonder if there was something more to the story.
Similar situation, but I had (and still have) issues with the heart, and not sure whether they were from undiagnosed covid infection (never had typical Covid symptoms, and all tests for it came negative), or some rare complications from the vaccine.
I started having heart flutters a day or two after my shot and had severe fever (I was 25 at the time), but the former never went a way. I brushed it off as a temporary symptom and typical after shot reaction (well, fever was at least). Heart flutters never went away and I didn't go to the doctor for at least a few months, it became so frequent that I could not sleep, exercise or even climb the stairs anymore without heart feeling like it's about to explode out of my chest. Not the high heart rate, but abrupt, irregular vibrations/twitching and sometimes feeling like you get punched in the chest, just from the inside around the heart area. Anyway, it happens frequently and in any situation, even at rest.
Got diagnosed with third degree AV block. The flutters were due to the significant damage to the heart muscle, which caused the failure of the conduction system - signals from the upper chambers did not always reach the lower chambers.
I am not angry at anyone or anything, just disappointed. It would feel a lot easier if it was some obvious bad decision of mine, like drinking, doing drugs, smoking, or being overweight, but I did not nor were any of these things. I still keep categorizing life as "before" and "after".
Perhaps its a reflection of how hard it is to get the medical community to take Long COVID seriously ?
I would say there is more chance of them (sadly) telling you to go home, take a couple of paracetamol and get some rest. Or if you're lucky, they might mis-diagnose you with something else....
(No first-hand experience here, just going by one or two anecdotal stories I've heard on the grapevine)
> Perhaps its a reflection of how hard it is to get the medical community to take Long COVID seriously ?
Well let’s think about why. You’ve got an illness (Long COVID) that you can’t detect and manifests itself in a myriad of ways, most of which are very vague and subjective (“brain fog” or “I can’t exercise as much as I used to”) and also not detectable.
Is it any wonder doctors might think of it as today’s fibromyalgia?
Ironic perhaps that Fibromylgia has been chosen given there are tests for the small fibre neuropathy that causes and it now has a firm diagnostic pathway.
The same will happen for Long Covid and ME/CFS, the diagnostics are there in research, they even show up in scans and tests that can be run in healthcare systems today, its just there is a resistance to run them.
A lot of symptoms of long covid mirror the symptoms of unhealthy living, which may make it so people either dismiss their own symptoms and don't seek diagnosis, or their complaints are dismissed by others for needing to simply improve externalities.
Couldn’t it be the other way round, that changes in health caused by other external factors erroneously get blamed on COVID?
For instance, a disproportionate amount of long COVID cases are reported by women between the ages of 40 and 60, the exact age range when most women experience menopause [0]. Menopause can cause brain fog, fatigue, and other symptoms that mirror those of long COVID. Since pretty much everyone has had COVID, it’s a basic statistical certainty that many women caught COVID exactly when their menopausal symptoms started (whose onset can be extremely sudden), and falsely causally associate the two. The exact same conflation likely happens in children, who also go through several profound developmental shifts.
>It is possible, but not to the degree that all long Covid cases are being confused with external factors.
Didn't mean to imply that all cases are, just that our definition of and knowledge about long COVID is nebulous enough that some nontrivial proportion of cases are likely attributable to external factors.
>Additionally, long Covid can cause brain fog. This was shown in brain scans from a popular HN post about a research paper just yesterday
Absolutely, just as other infections can cause severe lingering symptoms [0]. But we don't really know how prevalent these are, nor the severity of the prevalence. Studies like the one you link typically select for the most severe cases. We don't know whether it's useful to generalize from those.
You can't see "brain fog" on any imaging scan. That study didn't demonstrate any such causation. At most you can establish a correlation between certain imaging patterns and patient symptoms (which are notoriously noisy for any sort of behavioral health condition).
I went on vacation, had a great time, then got COVID, and came back a completely nonfunctional wreck beset by random adrenaline dumps, heart palpitations, spontaneous panic attacks, and wicked insomnia. The condition lasted almost a year.
39 year old male. I was in great shape both physically and mentally before my trip.
Fine, here's a source where both the second and corresponding authors are from Harvard that says the same thing [0]. That said, you don't need to be from a prestigious institution to observe the basic statistic that long COVID is most frequently reported in women ages 40-60.
Doctors are at complete a loss to "diagnose" long COVID. There are only a few places which specialize in it, and even then I think they're probably grasping at straws.
The numbers in the range of 1/5 usually include in the definition things like "a cough that lasts six weeks after the acute phase of infection and then goes away," which is not what most people think of when they hear the term Long COVID (and is not even unique to SARS-CoV-2).
For a variety of reasons, hyping the threat of infection has been a pretty widespread practice among the medical and scientific community since COVID began. There's no way on earth 1 out of 5 kids are still experiencing symptoms 3 months out.
The paper says "One in five children." I wouldn't be surprised at all. Children are very dynamic, changing often as they grow and go through different developmental stages (which may include periods where they seem more tired or more cranky, etc)
. They also often lack the language and agency to explain what's going on with their bodies.
I don't see how you'd know the exact number without a solid diagnostic check.
Could it be that you can have different severity of long covid? Someone with very severe symptoms will notice it but someone with small symptoms might not realise it (and instead think they are just less fit)
Not sure it's relevant at all, but a therapist who's working with kids in a large clinic in Berlin told me that anorexia cases in kids have doubled since COVID. He said they don't have the infrastructure to treat all those kids. It's pretty dramatic. That being said, I wouldn't be surprised if a large portion of those cases were really caused by long COVID.
I have a 87 year old uncle who says he has long covid because he gets tired and needs a nap in the afternoon. I'm half the age and felt the same even before 2020.
I haven't looked it up but often odd numbers like that are often due to the paper looking at people who were hospitalised for covid which is a small percentage of those who get it.
Acute, in this context, just means the infection had a finite (and usually relativity short) duration. The opposite is a chronic condition, which is what “long covid” would be in this case.
With the math of reinfection, and percentages generally being lower than reality, long COVID is likely much more common and widespread in more people than not.
That spread has been consistent in the literature for a long time. It depends on what symptoms you are looking for. Frankly, I trust the consistent message from the literature. Long covid is extremely prevalent but not always visible
Most people don't even know to look for it, including doctors. Some cardiac doctors are finally beginning to take the research more seriously, however. It's slow going for everyone involved.
Im not sure if this is a comment generated by a bot, a troll or something else to try and generate disinformation or something. I've seen a few comments on this thread which seem out of line from the usual sort of good natured discourse seen on HN. Not sure if its this particular topic or a sign of the times.
Anyway, having had long covid myself for over 15 months, there are many, many people suffering with it, we are just discovering the tip of the iceberg
Yeah the paper is just lying. “Long Covid” is just a typical response to a severe flu. Many people are just ignorant of the fact that flus can weaken the immune system past the initial infection. It’s well meaning attempt to understand common flu symptoms but they are just relating to COVID to get more clicks and funding.
Did you actually look at any part of the paper? Their approach is not some hand-wavy qualitative measure. They are measuring an actual phenomenon in people with known COVID infections. If you have a methodological problem with the paper, try using facts next time.
Society is very stratified by intelligence, and the predispositions to long covid, like generalized joint hypermobility (GJH) strongly correlates positively with intelligence. See the work done by Dr Jessica Eccles on Bendy Brains Bendy Bodies and her published studies on long covid.
Anyway, because of the stratification many people don’t know anyone with long covid, while at the same time half of my friends have it. Both can be true observations of our surroundings.
On the actual numbers I would say that ~10% get some level of Long Covid while half of those recover in the first year. Of those who don’t recover around half have GJH which is a massive over representation suggesting a strong predisposition.
This is (probably) not a Long Covid story but I found that bloodletting (for which I even received money!) gave me back the energy that I was missing for the last few years (e.g. it was impossible to build stamina). I also read about a study about the positive effects of bloodletting[1] that somehow is not all the rage in mainstream news, which I find perplexing. If it might be so easy to improve your health (for some of us), why isn't this discussed or studied more broadly?
"the patients who gave blood had a significant reduction in systolic blood pressure (from 148 mmHg to 130 mmHg) as well as reduction in blood glucose levels and heart rate, and an improvement in cholesterol levels (LDL/HDL ratio)."
The modern version of this is called Therapeutic Plasma Exchange (TPE) or Plasmapheresis and it is used to treat a variety of conditions including cancer and autoimmune:
I live in an area with PFAS contaminated ground water (which I now aggressively filter.) To me giving blood just kind of makes sense, if there is a class of things that can enter your blood and never leave, and does not replicate on its own, why not perform a regular "oil change" and hopefully help some people at the same time. Some study has been done:
The study specifically does not look at the effect on recipients, though the donation centers do not disallow such donations. My presumption is that the donation is a net positive all around. If study comes to show the contrary, I'll certainly revise my approach.
“I’ll do something which might be beneficial or harmful to me (I don’t know) and if given evidence of harm (likely never) I’ll stop doing it.” Ok…have fun I guess.
The person you responded to didn't say anything about harm to themselves. They said there's nothing stopping them from donating even though they're aware of the PFAS contamination in their area.
And from what I understand, PFA contamination has no bearing on whether or not you can donate.
The post implied that doing a “blood oil change” was potentially a good thing. My point is, we don’t know either way, because a study hasn’t looked at that question for health outcomes. It could be doing more harm than good, the parent commenter doesn’t know.
I assume we are built to lose some blood. I imagine throughout most of our species development, injuries were somewhat common on a regular basis. Just looking at the scars on my own body, from a quite active childhood and young adult period outdoors, I am extrapolating. n = 1
It didn't always have to turn into an infection as there are plenty folk methods of preventing that from happening used throughout history - from wound cauterisation to my regional bread + spiderwebs.
The latter was given a scientific explanation in modern times: the webbing contains live penicillium fungi in quantities sufficient to act against microbes.
This is why most women spent most of their adult life pregnant and there's still lingering moral pressure to have children. Societies, especially as they advanced, had real trouble maintaining population through reproduction alone.
You've also probably lived your whole life in urban areas shaped by personal injury lawyers and don't spend your life doing hard labor so you may not have gotten any serious cuts or broken bones because if your lifestyle.
I’ve got scars all over my body from cuts and scrapes. Some even needed stitches, back when that was a thing (now we just use some magic glue)! I’ve been lucky to never have a broken bone, but it wasn’t for lack of trying!
I didn’t live in an urban area until I was in my late 20s.
The lower blood pressure I can explain by having a lower volume of blood. But the glucose and cholesterol have to go somewhere. Where do they go? Are they filtered in the process after blood letting?
Let's just pretend it's accurate and say your body burns 2000 kcal a day. If you have less glucose in your blood overall after giving blood, even if the ratio should theoretically remain the same, your body is still going to burn 2000 kcal anyway, and maybe the blood glucose equilibrium reaches a lower level.
Yes, but the relative amount per volume blood should be the same. I think that's why he's asking.
If so, the answer is that the body replenishes plasma in a day and red cells in six weeks (redcrossblood.org FAQ). The relative amount does change quickly.
There is very little glucose in circulating blood at any given time. Unless you have severe uncontrolled diabetes (or a similar condition) your body regulates blood glucose level within a low, narrow range. Most glucose is stored in the muscles and liver as glycogen.
Menstruating women don't lose nearly that much blood.
Even if they did, the hormonal effects would likely swamp anything else. Which is a huge problem: women are routinely excluded from studies to avoid that, meaning we have no idea what the effects are on women.
This has been done. Women seem to have certain health benefits that stop after menopause. Reading about it was the first time I wondered whether blood letting made sense.
God, this is so ignorant, the hormonal changes (loss of estrogen) are the cause of increased risks for heart disease and osteoporosis and changes in metabolism post-menopause. Nothing to do with not physically losing blood, FFS.
There are likely multiple causal factors behind the health differences. Hormonal changes are one piece of the puzzle but so far no one has conclusively proved that physically losing blood has zero effect. The research just hasn't been done yet so we can't definitively say one way or the other.
There is a significant difference in the rate of major adverse cardiac events between menstruating women versus men and post-menopausal women, even after controlling for age and other factors. The periodic blood loss might account for at least part of the difference although the exact mechanism of action hasn't been clearly established. So it's possible that donating blood (or bloodletting in general) could have a preventive effect.
I looked up the amount of blood lost due to a menstruation cycle, and the answer is around 50 ml.
OP's linked paper has "the iron-reduction patients had 300ml of blood removed at the start of the trial and between 250 and 500ml removed four weeks later."
A blood donation removes 500 ml, so about a year of menstruation all at once. You can donate every two months, besides.
So, yes, if there is an effect then we might expect the magnitude of the effect to differ. Or else we'd expect a paper cut to also have the same effect.
Yeah sounds like you get your medical advice from the Kremlin. There no conspiracy to hide the medical benefits of leaching, can you imagine if that actually worked? Every doctor in the world would have to be a complete moron not to notice.
I don't know why they decided to use the term "blood letting" but I'm pretty sure some of the benefits being talked about in the response also come from donating blood (which is essentially the same thing)? You calling it "leaching" doesn't seem good faith
> I also read about a study about the positive effects of bloodletting[1] that somehow is not all the rage in mainstream news, which I find perplexing. If it might be so easy to improve your health (for some of us), why isn't this discussed or studied more broadly?
If this works, how is anyone going to make money off of it?
The title should be edited. It sounds as if the test is 94% accurate at detecting long covid, but in fact it's 94% accurate at counting microclots
> We estimated a 94% accuracy for the microclot count using the devices, significantly higher than the traditional counting of microclots on slides (66% accuracy)
> We evaluated the diagnostic power (...). We estimated a 94% accuracy for (our method), significantly higher than the (traditional method) (66% accuracy).
Both methods have counting in their name, but they are comparing the diagnostic power.
The sensitivity of such a test would be 0. This test had a sensitivity of 91% versus 61% for the glass slide count method, which is a large improvement.
The sample size is pretty small here and the control group even smaller. The paper concludes that a larger study is necessary to confirm the result.
If you read the actual link I don't think they're saying that using it as a covid test with some specific threshold of microclots has a 94% accuracy but just that the raw microclot count has a 94% accuracy.
The title on hn which implies that seems to be inaccurate and it's not the original title of the article.
No, that does not seem to be what they are saying.
> We evaluated the diagnostic power of the device in a cohort of 45 LC patients and 14 healthy pediatric donors. We estimated a 94% accuracy for the microclot count using the devices, significantly higher than the traditional counting of microclots on slides (66% accuracy).
They are comparing the predictive power and using accuracy (instead of sensitivity, recall, F1, etc.). For their method "using the devices", they compute an accuracy of the predictive power, not of the count, of 94%. For the previous method they say the accuracy is 66%.
Basic questions: Is accuracy even a good metric for this? Is 94% a good value or just the difference between bad and very bad?
It might very well be that their improvement is from bad to really good, but the point is that a raw stat of "94% accuracy" is useless without context and so is the headline.
OK, I looked at the actual paper, and what 94% actually is is the 0.94 area under the curve for the receiver-operating characteristic curve (the plot of the true positive rate (TPR) against the false positive rate (FPR) at each threshold setting) not the accuracy for a specific binary result (e.g. at a specific arbitrary threshold).
> In general, an AUC of 0.5 suggests no discrimination (i.e., ability to diagnose patients with and without the disease or condition based on the test), 0.7 to 0.8 is considered acceptable, 0.8 to 0.9 is considered excellent, and more than 0.9 is considered outstanding
That is exactly why I gave the trivial example of an "always No" test. It has perfect specificity (zero false positives) and has accuracy corresponding to prevalence. The sensitivity is zero, however, which is the point.
The paper explains what it actually means, so it's not nonsense. See my other comment https://news.ycombinator.com/item?id=45558941 it's the area under the curve for the receiver-operating characteristic curve and 94% is extremely good.
The primary conclusion of this research was basically just "this looks like it would be worth doing more research on." Which is a fair conclusion for a study this small.
Can someone knowledgeable explain the current understanding of Covid’s long time effects? I thought it was still a big unknown and long COVID was still debated as to even having a clear definition.
The WHO [1] has a clinical definition of the disease and some basic data on chance of Covid infections turning into Long Covid. Then the meta study by Eric Topol and Zayad Ali-al from last year is probably a good primer into what is known about the disease that is well established science [2].
Its not a big unknown anymore, its very prevalent, it has a lot of symptoms, it has a clinical definition but its problematic and there are many diagnostic tests that can detect parts of the condition but none has yet reached sufficient prominence to be adopted by healthcare. Healthcare is largely ignoring that Long Covid exists so you can't get diagnosed with it but its very much a real thing and a lot of people have it.
The first link is not a clinical definition, the second link is not a "meta study" (it's a substack article with absolutely no rigor). Moreover, the first link cites prevalence numbers wildly in conflict with the second link:
> Approximately 6 in every 100 people who have COVID-19 develop post COVID-19 condition
vs., for example:
> From one center in Wuhan, 1,359 survivors completed 3-year follow up and 54% had at least one persistent symptom of Long Covid
This only underscores the lack of clinical definition. Both of these suffer from the same fundamental error, which, again, is that there's no precise definition of the syndrome. They include symptoms that are common amongst healthy people, mix them with less-common things that are associated with Covid (e.g. anosmia) and try to call this a disease state. See the WHO's grab-bag list of possible inclusion criteria:
> Over 200 different symptoms have been reported by people with post COVID-19 condition. Common symptoms include: fatigue, aches and pains in muscles or joints, feeling breathless, headaches, difficulty in thinking or concentrating, alterations in taste.
So literally having "headaches" or "aches and pains" is enough to claim Long Covid, according to the WHO.
The Topol/Aly substack engages in the same logic, and you will see that the referenced charts and graphs cover everything from fatigue to heart attack. Aly, in particular, has based his entire long covid research on a single dataset of (largely elderly, unhealthy prior to infection) VA patients that he refuses to release, and routinely engages in statistical fishing expeditions for new "symptoms" within that dataset.
I did read the article. It only talks about detecting long covid in children, which is different to understanding its effect on adults and the long terms effect of COVID in general (vs long COVID, which if understand correctly it’s a different syndrome to just “ long term expected outcomes from having had COVID”).
Hypothesis: microclots are caused by the viral spike protein. The mRNA vaccine produces the viral spike protein. Therefore, a non-zero percentage of microclots are caused by spike protein originating from the vaccine.
One of the working theories on people suffering long COVID-like symptoms after receiving an mRNA COVID vaccine may apparently be related to spike proteins found in the patient's blood far longer than is typical/intended. This is apparently similar to long COVID patients.
At least, that's my layman's understanding when I was following it some years ago. I'm not sure if there's been more recent studies that have found more concrete links since then, but I suspect GP is in the same boat, which is why they asked.
Throwing out this random data point: I know several people who I believe have some sort of what could be called "long covid". Here's the weird thing though: all these people are some level of covid denier/vax skeptic type person. They themselves don't believe they have long covid (and in some cases don't even believe they had covid). But all of them conform to this pattern (as observed by me): 1. They had covid, 2. Immediately after they developed some weird long term symptoms that no doctor can explain.
Obviously there's some probability this is all coincidence but it does seem strange, especially considering the predisposition for these people to not think their issues were triggered by covid infection.
The paper claims that 1/5 of people experience Long COVID after an infection. Given that approximately everyone has caught COVID by now, this does not track with how rarely I've heard of people with it.
Wikipedia lists much lower numbers on https://en.wikipedia.org/wiki/Long_COVID (6–7% in adults, ~1% in children, less after vaccination.) and seems to use a more liberal definition than this paper, as it mentions "Most people with symptoms at 4 weeks recover by 12 weeks" (while the paper only considers it "long COIVD" if symptoms last past 3 months).
I've found studies (peer reviewed, as far as I can tell) claiming anything from well under 10% to well over 30%.
What's going on here?
I won't make a claim to the accuracy of the numbers, but I can offer an example of how long COVID can be undercounted. My daughter was a competitive long distance runner. Months after recovering from the acute symptoms of COVID, her performance numbers were still about 10% down and no amount of training would allow her to reach her previous level of performance. After many visits to doctors and specialists, she was eventually diagnosed with long COVID due to lung damage. She's still very fast by most measures, but in track, the difference between being in the 99th percentile and the 89th percentile is the difference between a top 3 finish and a bottom 3 finish. This basically ended her track career. In our case, if we didn't have hard data tracking her before and after performance levels, we may not have ever noticed a difference. How many people who aren't competitive athletes are walking around with 10% degraded pulmonary function and just didn't notice?
It's a pretty sad reflection of the times that there's a need to create a throwaway account to talk about long COVID symptoms, but this is a good personal anecdote to draw attention to what's likely happening. In my case, I only caught covid once - somepoint last year just before I would've gotten the updated booster. It took me well over a year to stop having acute pulmonary issues, and my lung performance is down year over year (measured during high intensity training) even though I finally feel no differently at baseline than I did before I caught it.
Most people don't exploit the full capacity of their bodies and so would never notice, which is essentially the point OP is making. This disease very likely ravaged the 20% claimed, but the vast majority may never know because they're just never pushing their bodies hard enough.
I mainly created the throwaway because I'm sharing personal medical information and I'd rather not do that with my main account where people know me IRL.
Yeah fair enough. lol
It ought to be possible to test that hypothesis by comparing publicly available race results for the same athletes on the same courses before and after the pandemic relative to the expected age-related performance loss. Anecdotally as an age-group endurance athlete I'm not seeing any big declines in myself and my friends so I'm highly skeptical that 20% were "ravaged". The actual incidence of significant loss of pulmonary function is probably much lower although I have no idea as to the actual number.
If anyone wants to quantify this then Athlinks is a good place to start for race results. Obviously the data is somewhat noisy, like you'd have to throw out the slower finishers who maybe weren't trying hard. But if there's a significant correlation then it ought to show up.
https://www.athlinks.com/
> you'd have to throw out the slower finishers who maybe weren't trying hard. But if there's a significant correlation then it ought to show up.
Poor performers and no shows are exactly the population you’re looking for. To be clear the argument isn’t about a 10% decline across the board among people with long COVID as there’s non cardio pulmonary symptoms like brain fog, loss of smell, and difficulty sleeping.
If 80% of the fit population had COVID, 20% of them had long COVID, and half the people with long COVID had a 10% decline in race performance. That’s something like an overall 0.8% drop of performance assuming nobody dropped out or joined, but again you’re loosing people on both sides who were most impacted. Thus I’d be highly skeptical of finding an actual connection here rather than something else that impacts more people.
A more useful approach is to take a cohort of people who raced in 2019 and track what happened to every single one of them specifically.
This makes sense. I would've been marked as a "no show" because I had to rescind a job offer because of long COVID which lasted a year. From the government's point of view I was just an unremarkable figure prolonging my bout of unemployment when in fact I had a great job offer lined up that went to shit because I got COVID while on my little bit of celebratory vacation
The PVCs, adrenaline dumps, sleeping problems and anxiety/panic were insane! The doctor thought that my hypothalamus was inflamed because of COVID.
You can test it for endurance athletes, but not necessarily for the population at large.
If long COVID disproportionately affects people who are sedentary, then you won't see that in endurance athlete performance.
I was a highly trained endurance athlete my entire life and covid/long-covid absolutely destroyed all of that, permanently
After 5 years I would happily trade only a 10% performance loss for the days and nights full of nerve damage pain (neuropathy)and what seems to be 30% performance loss
BTW very relevant to your daughter's story:
the first year of long-covid I was absolutely certain I had permanent lung damage and started searching everywhere for solutions
There are two possibilities that might be hopeful for her
The first is that it might not be permanent alveoli damage (which do not regenerate in humans) but rather obstruction from a "hydrogel" that forms during active covid and takes many many months if not years to dissipate entirely
1. https://images2.imgbox.com/98/e1/gw8bO0ug_o.png
The second is much more serious and not available in the United States except experimental trials for other diseases
2. "Inhaled Tissue Plasminogen Activator" or "Nebulised Rt-PA"
https://www.google.com/search?q=Nebulised+Recombinant+Tissue...
https://academic.oup.com/qjmed/article/113/8/539/5818885 (look at the photos in this second link)
BUT there's something you can try right away
see this table of plasminogen activators
* https://pmc.ncbi.nlm.nih.gov/articles/PMC5553328/table/t0001...
at the bottoms is Nattokinase and Serrapeptase
which are simple enzymes, you can buy Natto-Serra on Amazon and very very slowly perhaps over many months it might help her lungs (this is just a guess)
Thank you for the information, and I'm sorry to hear about your struggles.
> The first is that it might not be permanent alveoli damage (which do not regenerate in humans) but rather obstruction from a "hydrogel" that forms during active covid and takes many many months if not years to dissipate entirely
I didn't go into too much detail in my original post, but we think this is likely what happened to my daughter. Post-COVID, she could still go for long durations at 80% but when she pushed her limits, she would hit a wall and start to experience asthma like symptoms along with the feeling like she had mucous in her lungs that she couldn't get out. It took close to 2 years for her to stop experiencing those symptoms, at which point her competitive running peers had passed her by. She's happy to be able to enjoy running again but she did lose out on the competition part.
It takes very severe disability for it not to be brushed off as depression, anxiety, burnout, or blamed on lifestyle.
Additionally, a lot of those numbers are based on earlier strains of COVID, which were much more severe.
I suspect the 1/5 figure is largely true for "has some degree of cardiovascular damage and worsened general health after COVID", but the number of people actually disabled by the condition is much lower.
That said, any loss of ability is a sad thing, and I am incredibly disappointed that we did not introduce any shared indoor space air quality legislation post-pandemic.
And the lipid nanoparticle based Covid prevention shots caused myocarditis in some younger males, so earlier incidence of cardiovascular complications vs. the present (when most people especially younger healthy males are choosing not to take updated boosters) would correlate with that as well.
They did but if you go through the actual studies, the incidence of myocarditis was low, and almost all cases were non-serious, with no measured long-term impacts.
Further, the studies on long COVID incidence in vaccinated vs unvaccinated people suggested that the rates in vaccinated individuals were lower, though iirc it was only by something like a third or half. (among people who were symptomatic, at least, the total protective effect was likely greater)
The one Thai prospective study that I saw on this subject (the only one I ever found which measured biomarkers of heart damage like troponin before and after injection, which is utterly shameful), estimated a rate of heart damage in adolescent males in the range of 1-3%. So even that would be nowhere near enough to reach the 1/5 number.
I got pericarditis bad enough that I thought it was going to kill me but not bad enough to show up in any test. Thankfully the cardiologist accepted my description of what I felt and prescribed me colchicine which worked. I guess it would be called subclinical pericarditis and it would be good to have some stats on how often that happens.
I suspect many people commit the grave sin of mixing data sources to derive percentages, which seems almost impossible not to do in this case. I also strongly suspect that rates of infection (the denominator in question) were inflated to some extent during the pandemic as insurers and hmo were incentivized to detect covid even when it may not have been the primary reason for presenting. There were also disincentives or at least a lack of incentive to detect teratogenic effects of the lipid nanoparticle based preventative, and unfortunately likely personal biases as the preventative was highly politicized. But I’m not thinking about it much deeper than that, so you may be right.
The reported rates might have been inflated compared to what people presented with, but wastewater tracking and excess death measures all suggest that as a whole, infections were severely under-counted, possibly by a factor of up to over 2x.
Majority of the studies on myocarditis after vaccination found very low rates, with close to zero moderate to serious cases, and a full return to baseline of whatever the metrics studied were, I don't remember.
> Additionally, a lot of those numbers are based on earlier strains of COVID, which were much more severe.
Long COVID associated with SARS-CoV-2 reinfection among children and adolescents in the omicron era
https://www.thelancet.com/journals/laninf/article/PIIS1473-3...
(The same omicron era the media originally claimed was "not as bad as previous variants." Perhaps not in the acute phase, but as we've seen, that's the least of anybody's concerns who track the longterm risks.)
> I am incredibly disappointed that we did not introduce any shared indoor space air quality legislation post-pandemic.
That seems like a tempting thing to lament, and I did too until seeing this recently:
Study finds HEPA purifiers alone may not be enough to reduce viral exposure in schools
https://www.eurekalert.org/news-releases/1101354
This suggests our most reliable protection to date is consistent N95 usage (since present vaccines don't reliably prevent transmission) until next gen vaccines are developed.
There's more to air quality than HEPA filters. In-line far UV sterilisation, ventilation to reduce rebreathing and CO2 levels, and HEPA might not be enough as a single-building intervention, but it would almost definitely change disease spread dynamics if deployed world/nation wide.
> There's more to air quality than HEPA filters.
Agreed. In fact, even before COVID this was long overdue to be addressed in classrooms etc:
> ventilation to reduce rebreathing and CO2 levels
Unfortunately since that hasn't happened yet, methods like:
> In-line far UV sterilisation
> HEPA
are not effective. It isn't that they don't kill/stop the virus. The problem traces back to the inadequate forced air exchange and distribution which these methods require, and which is often a show stopper when you're talking about retrofitting existing structures without costs becoming insane. At a certain point it's easier to build new with these things in mind (and we absolutely should be taking requirements to do so more seriously).
> might not be enough as a single-building intervention, but it would almost definitely change disease spread dynamics if deployed world/nation wide.
The point of the previously linked study is to demonstrate that "something is better than nothing" reasoning doesn't always apply. We need to go big to see an actual measurable improvement over longer time spans. Otherwise, what's the benefit seen if you delay an average (but inevitable) infection from occurring by X days? There basically is none.
> Otherwise, what's the benefit seen if you delay an average (but inevitable) infection from occurring by X days? There basically is none.
It reduces the R0 factor, which reduces the amount of people that need to be resistant for herd immunity to take place, and which makes it easier for other measures to bring it down further, potentially below 1 where the disease dies out instead of continuing to spread.
The legislation and policy changes being introduced is to remove funding and access to vaccines. Of course we will not legislate for clean air.
If you get a diagnosis at all, it's going to be a catchall for "idk" like fibromyalgia, CFS, allergies or it's filed away as psychosomatic.
There are probably a lot of syndromes caused by latent infections from virii like EBV, various herpes, HPV, etc that don't go properly diagnosed or treated if they can be treated at all.
Also, it's been found that some viral infections retreat to tissues where their detection might be difficult/impossible without biopsy. You saw this with, for example, Ebola, where survivors could test negative for the virus, but it would still survive and replicate in different isolated tissues like those in the eye.
After covid I suffered from intermittent brain fog for years and also felt like my heart was maybe struggling more than usual when I was training at the gym.
Never enough to warrant going to a doctor unless I was being super paranoid (and spend a long time convincing them I wasn't paranoid) but just enough to always wonder if there was something more to the story.
Similar situation, but I had (and still have) issues with the heart, and not sure whether they were from undiagnosed covid infection (never had typical Covid symptoms, and all tests for it came negative), or some rare complications from the vaccine.
I started having heart flutters a day or two after my shot and had severe fever (I was 25 at the time), but the former never went a way. I brushed it off as a temporary symptom and typical after shot reaction (well, fever was at least). Heart flutters never went away and I didn't go to the doctor for at least a few months, it became so frequent that I could not sleep, exercise or even climb the stairs anymore without heart feeling like it's about to explode out of my chest. Not the high heart rate, but abrupt, irregular vibrations/twitching and sometimes feeling like you get punched in the chest, just from the inside around the heart area. Anyway, it happens frequently and in any situation, even at rest.
Got diagnosed with third degree AV block. The flutters were due to the significant damage to the heart muscle, which caused the failure of the conduction system - signals from the upper chambers did not always reach the lower chambers.
I am not angry at anyone or anything, just disappointed. It would feel a lot easier if it was some obvious bad decision of mine, like drinking, doing drugs, smoking, or being overweight, but I did not nor were any of these things. I still keep categorizing life as "before" and "after".
> What's going on here?
Perhaps its a reflection of how hard it is to get the medical community to take Long COVID seriously ?
I would say there is more chance of them (sadly) telling you to go home, take a couple of paracetamol and get some rest. Or if you're lucky, they might mis-diagnose you with something else....
(No first-hand experience here, just going by one or two anecdotal stories I've heard on the grapevine)
>Perhaps its a reflection of how hard it is to get the medical community to take _____ seriously
There are a myriad of illnesses here that this seems to apply to.
> Perhaps its a reflection of how hard it is to get the medical community to take Long COVID seriously ?
Well let’s think about why. You’ve got an illness (Long COVID) that you can’t detect and manifests itself in a myriad of ways, most of which are very vague and subjective (“brain fog” or “I can’t exercise as much as I used to”) and also not detectable.
Is it any wonder doctors might think of it as today’s fibromyalgia?
Ironic perhaps that Fibromylgia has been chosen given there are tests for the small fibre neuropathy that causes and it now has a firm diagnostic pathway.
The same will happen for Long Covid and ME/CFS, the diagnostics are there in research, they even show up in scans and tests that can be run in healthcare systems today, its just there is a resistance to run them.
A lot of symptoms of long covid mirror the symptoms of unhealthy living, which may make it so people either dismiss their own symptoms and don't seek diagnosis, or their complaints are dismissed by others for needing to simply improve externalities.
Couldn’t it be the other way round, that changes in health caused by other external factors erroneously get blamed on COVID?
For instance, a disproportionate amount of long COVID cases are reported by women between the ages of 40 and 60, the exact age range when most women experience menopause [0]. Menopause can cause brain fog, fatigue, and other symptoms that mirror those of long COVID. Since pretty much everyone has had COVID, it’s a basic statistical certainty that many women caught COVID exactly when their menopausal symptoms started (whose onset can be extremely sudden), and falsely causally associate the two. The exact same conflation likely happens in children, who also go through several profound developmental shifts.
[0] https://telegraph.co.uk/news/2022/12/28/long-covid-may-actua...
> Couldn’t it be the other way round, that changes in health caused by other external factors erroneously get blamed on COVID?
It is possible, but not to the degree that all long Covid cases are being confused with external factors.
> Menopause can cause brain fog
Additionally, long Covid can cause brain fog. This was shown in brain scans from a popular HN post about a research paper just yesterday:
https://news.ycombinator.com/item?id=45539845
Those patients were 20-59 and had "no previous history of neuropsychiatric disorders."
>It is possible, but not to the degree that all long Covid cases are being confused with external factors.
Didn't mean to imply that all cases are, just that our definition of and knowledge about long COVID is nebulous enough that some nontrivial proportion of cases are likely attributable to external factors.
>Additionally, long Covid can cause brain fog. This was shown in brain scans from a popular HN post about a research paper just yesterday
Absolutely, just as other infections can cause severe lingering symptoms [0]. But we don't really know how prevalent these are, nor the severity of the prevalence. Studies like the one you link typically select for the most severe cases. We don't know whether it's useful to generalize from those.
[0] https://en.wikipedia.org/wiki/Post-acute_infection_syndrome
You can't see "brain fog" on any imaging scan. That study didn't demonstrate any such causation. At most you can establish a correlation between certain imaging patterns and patient symptoms (which are notoriously noisy for any sort of behavioral health condition).
I went on vacation, had a great time, then got COVID, and came back a completely nonfunctional wreck beset by random adrenaline dumps, heart palpitations, spontaneous panic attacks, and wicked insomnia. The condition lasted almost a year.
39 year old male. I was in great shape both physically and mentally before my trip.
Ah yes, you trust
https://www.newsonhealth.co.uk/
over research from Harvard.
One, maybe two non-research docs or... a team of research docs.
Fine, here's a source where both the second and corresponding authors are from Harvard that says the same thing [0]. That said, you don't need to be from a prestigious institution to observe the basic statistic that long COVID is most frequently reported in women ages 40-60.
[0] https://jamanetwork.com/journals/jamanetworkopen/fullarticle...
Doctors are at complete a loss to "diagnose" long COVID. There are only a few places which specialize in it, and even then I think they're probably grasping at straws.
The numbers in the range of 1/5 usually include in the definition things like "a cough that lasts six weeks after the acute phase of infection and then goes away," which is not what most people think of when they hear the term Long COVID (and is not even unique to SARS-CoV-2).
For a variety of reasons, hyping the threat of infection has been a pretty widespread practice among the medical and scientific community since COVID began. There's no way on earth 1 out of 5 kids are still experiencing symptoms 3 months out.
The paper says "One in five children." I wouldn't be surprised at all. Children are very dynamic, changing often as they grow and go through different developmental stages (which may include periods where they seem more tired or more cranky, etc) . They also often lack the language and agency to explain what's going on with their bodies.
I don't see how you'd know the exact number without a solid diagnostic check.
Could it be that you can have different severity of long covid? Someone with very severe symptoms will notice it but someone with small symptoms might not realise it (and instead think they are just less fit)
No, the paper says:
> Long COVID (LC) impacts one in five children after an acute SARS-CoV-2 infection
So, 20% of children that suffered of an acute SARS-CoV-2 infection, did not recovered immediately, but experienced also Long COVID.
Not sure it's relevant at all, but a therapist who's working with kids in a large clinic in Berlin told me that anorexia cases in kids have doubled since COVID. He said they don't have the infrastructure to treat all those kids. It's pretty dramatic. That being said, I wouldn't be surprised if a large portion of those cases were really caused by long COVID.
I have a 87 year old uncle who says he has long covid because he gets tired and needs a nap in the afternoon. I'm half the age and felt the same even before 2020.
I haven't looked it up but often odd numbers like that are often due to the paper looking at people who were hospitalised for covid which is a small percentage of those who get it.
>after an acute SARS-CoV-2 infection.
Maybe not all infections are considered "acute".
Acute, in this context, just means the infection had a finite (and usually relativity short) duration. The opposite is a chronic condition, which is what “long covid” would be in this case.
> this does not track with how rarely I've heard of people with it.
Maybe you are not the type of person that people feel comfortable to share their health problems information with.
With the math of reinfection, and percentages generally being lower than reality, long COVID is likely much more common and widespread in more people than not.
Agreed.
https://old.reddit.com/r/ZeroCovidCommunity/comments/1o40bpc...
That spread has been consistent in the literature for a long time. It depends on what symptoms you are looking for. Frankly, I trust the consistent message from the literature. Long covid is extremely prevalent but not always visible
I'm an ambulance chaser. I look at medical records all day. I've never seen anyone complaining of long covid.
Most people don't even know to look for it, including doctors. Some cardiac doctors are finally beginning to take the research more seriously, however. It's slow going for everyone involved.
Im not sure if this is a comment generated by a bot, a troll or something else to try and generate disinformation or something. I've seen a few comments on this thread which seem out of line from the usual sort of good natured discourse seen on HN. Not sure if its this particular topic or a sign of the times.
Anyway, having had long covid myself for over 15 months, there are many, many people suffering with it, we are just discovering the tip of the iceberg
Yeah the paper is just lying. “Long Covid” is just a typical response to a severe flu. Many people are just ignorant of the fact that flus can weaken the immune system past the initial infection. It’s well meaning attempt to understand common flu symptoms but they are just relating to COVID to get more clicks and funding.
Did you actually look at any part of the paper? Their approach is not some hand-wavy qualitative measure. They are measuring an actual phenomenon in people with known COVID infections. If you have a methodological problem with the paper, try using facts next time.
Society is very stratified by intelligence, and the predispositions to long covid, like generalized joint hypermobility (GJH) strongly correlates positively with intelligence. See the work done by Dr Jessica Eccles on Bendy Brains Bendy Bodies and her published studies on long covid.
Anyway, because of the stratification many people don’t know anyone with long covid, while at the same time half of my friends have it. Both can be true observations of our surroundings.
On the actual numbers I would say that ~10% get some level of Long Covid while half of those recover in the first year. Of those who don’t recover around half have GJH which is a massive over representation suggesting a strong predisposition.
This is (probably) not a Long Covid story but I found that bloodletting (for which I even received money!) gave me back the energy that I was missing for the last few years (e.g. it was impossible to build stamina). I also read about a study about the positive effects of bloodletting[1] that somehow is not all the rage in mainstream news, which I find perplexing. If it might be so easy to improve your health (for some of us), why isn't this discussed or studied more broadly?
[1]https://www.sciencedaily.com/releases/2012/05/120529211645.h...
"the patients who gave blood had a significant reduction in systolic blood pressure (from 148 mmHg to 130 mmHg) as well as reduction in blood glucose levels and heart rate, and an improvement in cholesterol levels (LDL/HDL ratio)."
The modern version of this is called Therapeutic Plasma Exchange (TPE) or Plasmapheresis and it is used to treat a variety of conditions including cancer and autoimmune:
https://my.clevelandclinic.org/health/treatments/24197-plasm...
There are also claims that it improves dementia / Alzheimer's symptoms and popular "longevity biomarkers".
I live in an area with PFAS contaminated ground water (which I now aggressively filter.) To me giving blood just kind of makes sense, if there is a class of things that can enter your blood and never leave, and does not replicate on its own, why not perform a regular "oil change" and hopefully help some people at the same time. Some study has been done:
https://pmc.ncbi.nlm.nih.gov/articles/PMC8994130/
The study specifically does not look at the effect on recipients, though the donation centers do not disallow such donations. My presumption is that the donation is a net positive all around. If study comes to show the contrary, I'll certainly revise my approach.
“I’ll do something which might be beneficial or harmful to me (I don’t know) and if given evidence of harm (likely never) I’ll stop doing it.” Ok…have fun I guess.
The person you responded to didn't say anything about harm to themselves. They said there's nothing stopping them from donating even though they're aware of the PFAS contamination in their area.
And from what I understand, PFA contamination has no bearing on whether or not you can donate.
The post implied that doing a “blood oil change” was potentially a good thing. My point is, we don’t know either way, because a study hasn’t looked at that question for health outcomes. It could be doing more harm than good, the parent commenter doesn’t know.
They linked a study in their comment.
I assume we are built to lose some blood. I imagine throughout most of our species development, injuries were somewhat common on a regular basis. Just looking at the scars on my own body, from a quite active childhood and young adult period outdoors, I am extrapolating. n = 1
Before antibiotics, nontrivial wounds were often death sentences because of infection.
I never needed an antibiotic to live from these wounds. I’ve needed them from other things (almost died from strep) but not wounds.
You live in a very different world compared to one before antibiotics.
If death were so guaranteed from injuries, I doubt we’d have survived as a species.
Before the discovery of antibiotics, chopping it off was the usual standard of care for serious infections.
It didn't always have to turn into an infection as there are plenty folk methods of preventing that from happening used throughout history - from wound cauterisation to my regional bread + spiderwebs.
The latter was given a scientific explanation in modern times: the webbing contains live penicillium fungi in quantities sufficient to act against microbes.
This is why most women spent most of their adult life pregnant and there's still lingering moral pressure to have children. Societies, especially as they advanced, had real trouble maintaining population through reproduction alone.
You've also probably lived your whole life in urban areas shaped by personal injury lawyers and don't spend your life doing hard labor so you may not have gotten any serious cuts or broken bones because if your lifestyle.
I’ve got scars all over my body from cuts and scrapes. Some even needed stitches, back when that was a thing (now we just use some magic glue)! I’ve been lucky to never have a broken bone, but it wasn’t for lack of trying!
I didn’t live in an urban area until I was in my late 20s.
> If it might be so easy to improve your health (for some of us), why isn't this discussed or studied more broadly?
I think you just need to reach for a literature that's a few hundred years older maybe.
The lower blood pressure I can explain by having a lower volume of blood. But the glucose and cholesterol have to go somewhere. Where do they go? Are they filtered in the process after blood letting?
Let's just pretend it's accurate and say your body burns 2000 kcal a day. If you have less glucose in your blood overall after giving blood, even if the ratio should theoretically remain the same, your body is still going to burn 2000 kcal anyway, and maybe the blood glucose equilibrium reaches a lower level.
If it's in the blood, doesn't it just leave the body together with the blood?
Yes, but the relative amount per volume blood should be the same. I think that's why he's asking.
If so, the answer is that the body replenishes plasma in a day and red cells in six weeks (redcrossblood.org FAQ). The relative amount does change quickly.
There is very little glucose in circulating blood at any given time. Unless you have severe uncontrolled diabetes (or a similar condition) your body regulates blood glucose level within a low, narrow range. Most glucose is stored in the muscles and liver as glycogen.
That's interesting - I've had low energy and somewhat raised blood pressure since covid. Maybe I'll give it a go.
If this were the case you could do a natural study on this by comparing menstruating women with the rest of the population
Menstruating women don't lose nearly that much blood.
Even if they did, the hormonal effects would likely swamp anything else. Which is a huge problem: women are routinely excluded from studies to avoid that, meaning we have no idea what the effects are on women.
This has been done. Women seem to have certain health benefits that stop after menopause. Reading about it was the first time I wondered whether blood letting made sense.
God, this is so ignorant, the hormonal changes (loss of estrogen) are the cause of increased risks for heart disease and osteoporosis and changes in metabolism post-menopause. Nothing to do with not physically losing blood, FFS.
There are likely multiple causal factors behind the health differences. Hormonal changes are one piece of the puzzle but so far no one has conclusively proved that physically losing blood has zero effect. The research just hasn't been done yet so we can't definitively say one way or the other.
There is a significant difference in the rate of major adverse cardiac events between menstruating women versus men and post-menopausal women, even after controlling for age and other factors. The periodic blood loss might account for at least part of the difference although the exact mechanism of action hasn't been clearly established. So it's possible that donating blood (or bloodletting in general) could have a preventive effect.
When people donate blood, on average they donate about 10x as much as a woman typically loses during menstruation.
I looked up the amount of blood lost due to a menstruation cycle, and the answer is around 50 ml.
OP's linked paper has "the iron-reduction patients had 300ml of blood removed at the start of the trial and between 250 and 500ml removed four weeks later."
A blood donation removes 500 ml, so about a year of menstruation all at once. You can donate every two months, besides.
So, yes, if there is an effect then we might expect the magnitude of the effect to differ. Or else we'd expect a paper cut to also have the same effect.
Sex biological difference could matter as well.
Yeah sounds like you get your medical advice from the Kremlin. There no conspiracy to hide the medical benefits of leaching, can you imagine if that actually worked? Every doctor in the world would have to be a complete moron not to notice.
I don't know why they decided to use the term "blood letting" but I'm pretty sure some of the benefits being talked about in the response also come from donating blood (which is essentially the same thing)? You calling it "leaching" doesn't seem good faith
> I also read about a study about the positive effects of bloodletting[1] that somehow is not all the rage in mainstream news, which I find perplexing. If it might be so easy to improve your health (for some of us), why isn't this discussed or studied more broadly?
If this works, how is anyone going to make money off of it?
Edit - this comment is incorrect
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The title should be edited. It sounds as if the test is 94% accurate at detecting long covid, but in fact it's 94% accurate at counting microclots
> We estimated a 94% accuracy for the microclot count using the devices, significantly higher than the traditional counting of microclots on slides (66% accuracy)
No, you are parsing this wrong.
> We evaluated the diagnostic power (...). We estimated a 94% accuracy for (our method), significantly higher than the (traditional method) (66% accuracy).
Both methods have counting in their name, but they are comparing the diagnostic power.
after reading more - you're right, I'm wrong
I appreciate the frank acknowledgment of your mistakes. We need more people like you.
94% accuracy sounds extremely bad, no?
https://www.ssph-journal.org/journals/public-health-reviews/...
> Prevalence estimated (...) 2%–3.5% in primarily non-hospitalized children.
So a fake test always saying "No" would be more accurate at 96.5% accuracy.
The sensitivity of such a test would be 0. This test had a sensitivity of 91% versus 61% for the glass slide count method, which is a large improvement.
The sample size is pretty small here and the control group even smaller. The paper concludes that a larger study is necessary to confirm the result.
That is exactly why I gave that example. Why does the headline focus on accuracy then?
To get you to click on it :-)
If you read the actual link I don't think they're saying that using it as a covid test with some specific threshold of microclots has a 94% accuracy but just that the raw microclot count has a 94% accuracy.
The title on hn which implies that seems to be inaccurate and it's not the original title of the article.
No, that does not seem to be what they are saying.
> We evaluated the diagnostic power of the device in a cohort of 45 LC patients and 14 healthy pediatric donors. We estimated a 94% accuracy for the microclot count using the devices, significantly higher than the traditional counting of microclots on slides (66% accuracy).
They are comparing the predictive power and using accuracy (instead of sensitivity, recall, F1, etc.). For their method "using the devices", they compute an accuracy of the predictive power, not of the count, of 94%. For the previous method they say the accuracy is 66%.
Basic questions: Is accuracy even a good metric for this? Is 94% a good value or just the difference between bad and very bad?
It might very well be that their improvement is from bad to really good, but the point is that a raw stat of "94% accuracy" is useless without context and so is the headline.
OK, I looked at the actual paper, and what 94% actually is is the 0.94 area under the curve for the receiver-operating characteristic curve (the plot of the true positive rate (TPR) against the false positive rate (FPR) at each threshold setting) not the accuracy for a specific binary result (e.g. at a specific arbitrary threshold).
See https://www.sciencedirect.com/science/article/pii/S155608641...
> In general, an AUC of 0.5 suggests no discrimination (i.e., ability to diagnose patients with and without the disease or condition based on the test), 0.7 to 0.8 is considered acceptable, 0.8 to 0.9 is considered excellent, and more than 0.9 is considered outstanding
So .94 is actually extremely good.
Accuracy is a nonsense word in this context
Tests have a sensitivity (1 - percentage of false negatives) and specificity (1 - percentage of false positives)
"Accuracy" usually refers to sensitivity. If specificity is near 100% and the test is cheap/fast even low sensitivity can be good
On the other hand you could have sensitivity of 100% but the test could be useless if specificity is low and the condition is rare
No, it is a well defined term in this context and does not refer to sensitivity.
https://pmc.ncbi.nlm.nih.gov/articles/PMC4614595/#:~:text=Ac...
That is exactly why I gave the trivial example of an "always No" test. It has perfect specificity (zero false positives) and has accuracy corresponding to prevalence. The sensitivity is zero, however, which is the point.
The paper explains what it actually means, so it's not nonsense. See my other comment https://news.ycombinator.com/item?id=45558941 it's the area under the curve for the receiver-operating characteristic curve and 94% is extremely good.
Sample size of 59 also seems worse than useless; I'm no researcher so maybe there's something I'm missing here but, doesn't seem very good.
Junk science?
It's just an early study, not junk.
The primary conclusion of this research was basically just "this looks like it would be worth doing more research on." Which is a fair conclusion for a study this small.
Can someone knowledgeable explain the current understanding of Covid’s long time effects? I thought it was still a big unknown and long COVID was still debated as to even having a clear definition.
The WHO [1] has a clinical definition of the disease and some basic data on chance of Covid infections turning into Long Covid. Then the meta study by Eric Topol and Zayad Ali-al from last year is probably a good primer into what is known about the disease that is well established science [2].
Its not a big unknown anymore, its very prevalent, it has a lot of symptoms, it has a clinical definition but its problematic and there are many diagnostic tests that can detect parts of the condition but none has yet reached sufficient prominence to be adopted by healthcare. Healthcare is largely ignoring that Long Covid exists so you can't get diagnosed with it but its very much a real thing and a lot of people have it.
[1]https://www.who.int/news-room/fact-sheets/detail/post-covid-...
[2] https://erictopol.substack.com/p/long-covid-at-3-years
The first link is not a clinical definition, the second link is not a "meta study" (it's a substack article with absolutely no rigor). Moreover, the first link cites prevalence numbers wildly in conflict with the second link:
> Approximately 6 in every 100 people who have COVID-19 develop post COVID-19 condition
vs., for example:
> From one center in Wuhan, 1,359 survivors completed 3-year follow up and 54% had at least one persistent symptom of Long Covid
This only underscores the lack of clinical definition. Both of these suffer from the same fundamental error, which, again, is that there's no precise definition of the syndrome. They include symptoms that are common amongst healthy people, mix them with less-common things that are associated with Covid (e.g. anosmia) and try to call this a disease state. See the WHO's grab-bag list of possible inclusion criteria:
> Over 200 different symptoms have been reported by people with post COVID-19 condition. Common symptoms include: fatigue, aches and pains in muscles or joints, feeling breathless, headaches, difficulty in thinking or concentrating, alterations in taste.
So literally having "headaches" or "aches and pains" is enough to claim Long Covid, according to the WHO.
The Topol/Aly substack engages in the same logic, and you will see that the referenced charts and graphs cover everything from fatigue to heart attack. Aly, in particular, has based his entire long covid research on a single dataset of (largely elderly, unhealthy prior to infection) VA patients that he refuses to release, and routinely engages in statistical fishing expeditions for new "symptoms" within that dataset.
I find the occasional research roundups from the “your local epidemiologist” newsletter informative:
https://yourlocalepidemiologist.substack.com/p/long-covid-re...
If only there were some sort of link here with that sort of information!
I did read the article. It only talks about detecting long covid in children, which is different to understanding its effect on adults and the long terms effect of COVID in general (vs long COVID, which if understand correctly it’s a different syndrome to just “ long term expected outcomes from having had COVID”).
Can they disambiguate between spike protein microclots produced by natural infection vs. those generated by the vaccines.
https://news.yale.edu/2025/02/19/immune-markers-post-vaccina...
They are looking into that.
I am curious about the working hypothesis leading to this question.
Hypothesis: microclots are caused by the viral spike protein. The mRNA vaccine produces the viral spike protein. Therefore, a non-zero percentage of microclots are caused by spike protein originating from the vaccine.
One of the working theories on people suffering long COVID-like symptoms after receiving an mRNA COVID vaccine may apparently be related to spike proteins found in the patient's blood far longer than is typical/intended. This is apparently similar to long COVID patients.
At least, that's my layman's understanding when I was following it some years ago. I'm not sure if there's been more recent studies that have found more concrete links since then, but I suspect GP is in the same boat, which is why they asked.
I've looked up quite a lot of research about vaccines doing damage and the usual result is yes they do but it's about 100x less bad than covid itself.
Throwing out this random data point: I know several people who I believe have some sort of what could be called "long covid". Here's the weird thing though: all these people are some level of covid denier/vax skeptic type person. They themselves don't believe they have long covid (and in some cases don't even believe they had covid). But all of them conform to this pattern (as observed by me): 1. They had covid, 2. Immediately after they developed some weird long term symptoms that no doctor can explain.
Obviously there's some probability this is all coincidence but it does seem strange, especially considering the predisposition for these people to not think their issues were triggered by covid infection.
Is it safe to assume that these children received the vaccine?
I don't see how we can differentiate between long covid and injury from mrna shots.