17 ms·
Direct evidence for T-cell immunity as a factor behind Covid-19 heterogeneity
- phendrenad2 6y agoSo basically this is saying that previous exposure to various versions of the common cold can lead to some covid resistance?
- verdverm 6y agoYes, we know this has been happening for 10,000s of years. The question now is to what extent, with SARS-CoV-2, is this the case based on a number of factors. It's a fundamental concept in epidemiology that hasn't been talked about enough. That is, pre-existing ability to fight off foreign cells because they body saw something close to it before. I think the obsession with the word "novel" has played a role in the public's perception. I'd expect geography to be a significant factor based on how viruses propagate on Earth
- wittyreference 6y ago> It's a fundamental concept in epidemiology that hasn't been talked about enough. Dunning-Kruger in action.
- verdverm 6y agoMind viruses appear to be much more toxic to the species, and spread faster by multiple orders of magnitude.
- wittyreference 6y agoI meant that cross-reactivity of acquired immune responses across coronaviruses is a topic that is constantly discussed in a wide swath of the literature on covid. Infectious disease isn't even my area of specialization and I see it on at least a weekly basis - I can only assume the actual epi and inf. disease lit tackles it more thoroughly. You're confusing "I'm not hearing about it in the pop media I consume" with "it's not being widely discussed by everyone in the field." Which is what happens when you try to evaluate a whole swath of experts in a topic you're not an expert in. Dunning-Kruger in action.
- verdverm 6y agoAgreed, was not referring to the researchers, rather those getting informed by the pop media. I've heard people dismissing this known process as an impossibility
- ithkuil 6y agoThe tricky thing is that while we humans do tend to seek out expert opinion on things we don't know, we also have a fundamental arrive to "understand" things. A big part of the job of a doctor is to find a way to explain things to their patient in a way that is tailored for them. Being too technical you won't get the point across; being to vague may be interpreted as you're grasping at straws, and being too condescending is more and more problematic in our modern societies with mass education. To a poorly educated person from the early 20 century, it was no big deal to just trust the doctor to do their doctory thing and talk in their doctory way. Them being condescending and confident was in character. A century later, the society is quite different. Most people received a nominally far better education than in the past, and grew up in a culture where everybody can become whatever they want, after all it's just a matter of educating yourself and hard work. Understanding is withing reach. "Perhaps we don't need to depend on those condescending twats in their white coats looking down on us!". At the same time, the vastness of knowledge gathered makes it so hard to actually master it. Being a proper member of the scientific community requires more and more education and team work and institution to coordinate all that. This provides a barrier to entry to all people who are interested in understanding the whys and the hows. As mentioned earlier, most people seek answers. For the answers to be trustworthy they either have to come from a trustworthy authority or they have to make sense (or better, a combination of the two). But trust in scientific authorities has been eroded over time by egregious failings (real or perceived) of white coats acting in bad faith, doing the bids of whoever provides for their salary, be it big tabacco, big pharma, food industries, etc. When that happened it resonated with the good old human fear of the unknown and mysterious and was fertile ground for the Hollywood persona of the white coat of dubious morality or at least gullible nerd. On the other hand trust in political authority is, well, political, thus fueling the search for alternative explanations when the official ones have politically connotations that go against one's own identity. It also helps that nowadays circulating information offers far less friction than in the past. You can easily devote that half hour to chime in with your deep insights about topics you ultimately have no clue about, like what I'm doing here right now.
- jjtheblunt 6y agoor geography updated to account for proximities just a flight away?
- verdverm 6y agoYes, it's far more complex today than just the ~2 decades since SARS-Cov-1. I'm wondering in cities with high volume airports saw it back in Jan/Feb here in the states.
- jjtheblunt 6y agoI wonder the same.
- somewhereoutth 6y agoThis virus is novel. The whole human population is immunologically naive to it. We don't know what affect it will have on us. Suppression/eradication is the only way forward.
- guscost 6y ago> The whole human population is immunologically naive to it. This study provides direct evidence that the “novel factor” is not as important as was previously thought. Maybe no-one has cleared a virus exactly like this one before (we can’t be sure), but it is looking more and more like many people have pre-existing immune responses that can clear this one. > Suppression/eradication is the only way forward. You may end up being right, but to me this is sounding less and less like a scientific conclusion, and more and more like a religious creed.
- joe_the_user 6y agoYou may end up being right, but to me this is sounding less and less like a scientific conclusion, and more and more like a religious creed. The way to say is ..."the only way we can count on" is eradication. Sure, keep working on the other approaches but relying on them is foolish.
- zaroth 6y agoI don’t know, SARS-CoV-2 may be the most well adapted and widespread potentially deadly human infection in the world right now. If any possible endpoint, “suppression/eradication” seems the least likely.
- __blockcipher__ 6y agoThis. SARS-2 is a great spreader but a poor killer. (See: SARS-2’a early course interferon-mediated immunosuppression which probably explains the presence of pre-symptomatic spread). Worst possible candidate for suppression. And eradication is literally impossible. It just shows how little these people know. It’s a zoonotic virus with abundant animal reservoirs, a high reproduction rate and pre-symptomatic spread. Even with a vaccine it fails the zoonotic requirement. It’s endemic and here to stay. Anyone paying attention has known that from the start. I’ve personally been saying this for months and I’m just a deterministic algorithm operating on fixed-length groups of bits called blocks.
- malwarebytess 6y agoSomething on the order of 40% of viruses that cause "colds" are corona viruses.
- sroussey 6y agoAround 4 coronaviruses cause colds in humans. Out of hundreds. But they are commonly distributed and cause more than their fair share of infections.
- danybittel 6y agoBut why are the elderly more susceptible? Shouldn't the probability of exposure by higher, the older you get? Wasn't that the reason the Spanish flu killed more younger people?
- lambdaba 6y agoAge isn't the factor, it's just a proxy for immune system dysfunction brought on by diabetes / metabolic syndrome etc.
- nxpnsv 6y agoAre elderly more susceptible to infection or adverse outcome once infected? In the latter case we still can see worse stats for the elderly.
- jhrmnn 6y agoThe response of the immune system to the virus and its mode of operation (deadliness) may be entirely unrelated. The T cells may react to some parts of the virus protein, other parts may be related to its effect in the body once infected.
- grumple 6y agoImmunity might only last for a few years. Older people probably get less exposure To recent viruses and have generally weaker bodies.
- nostromo 6y ago> We demonstrate a range of pre-existing memory CD4+ T cells that are cross-reactive with comparable affinity to SARS-CoV-2 and the common cold coronaviruses HCoV-OC43, HCoV-229E, HCoV-NL63, or HCoV-HKU1. Thus, variegated T cell memory to coronaviruses that cause the common cold may underlie at least some of the extensive heterogeneity observed in COVID-19 disease. Could we just start deliberately spreading these weaker cold viruses then?
- el_benhameen 6y agoMy kids are ahead of the curve. They've been doing that for years.
- RhysU 6y agoIt's like (cue Jurassic Park music) life finds a way.
- greesil 6y agoI really would like to see some data if parents of younger children fare better than others in the same age range.
- snowwrestler 6y agoGood joke, but since we're talking about kids... there is obviously more to Covid-19 heterogeneity than previous exposure to coronaviruses, since very young children are least likely to experience serious illness, but are also least likely to have a lot of exposure to other coronaviruses.
- w0utert 6y agoOne of the theories is that the density of the ACE2 receptor the virus binds to, is somehow correlated with testosterone levels, which is very low for young children, and low for women compared to men. This would provide an explanation why severe cases are extremely rare in young children, and comparatively high for men vs. women.
- 6y ago
- blargmaster33 6y agoC19study TDS is killing people
- armada651 6y agoThis would also explain why the anti-body tests have proved so unreliable. A lot of people already have reactive anti-bodies without being exposed.
- __blockcipher__ 6y agoReactive t cells, not antibodies.
- avancemos 6y agoFrom the abstract: "We demonstrate a range of pre-existing memory CD4+ T cells that are cross-reactive with comparable affinity to SARS-CoV-2 and the common cold coronaviruses HCoV-OC43, HCoV-229E, HCoV-NL63, or HCoV-HKU1." 1. Populations may naturally have a head start towards herd immunity from COVID. 2. Sweden could be really close in that regard; their current super low daily mortality and declining cases may point towards herd immunity.
- tapland 6y agoI wouldn't call it "super low" mortality when the average for the past month since the large drop is still 25x that of Denmark (i.e. nearly our neighbors montly totals per day), when it should be more like 2x based on population sizes (and Denmark being denser populated on top of that).
- trianglem 6y agoWhat are you talking about? Sweden has a much higher death rate when compared to its neighbors.
- albroland 6y ago"current" they are presently doing about as well as all their immediate neighbors for per-capita deaths: https://ourworldindata.org/coronavirus-data-explorer?zoomToSelection=true&country=SWE~DNK~NOR~BEL~POL~DEU~NLD&deathsMetric=true&interval=smoothed&aligned=true&perCapita=true&smoothing=7&pickerMetric=location&pickerSort=asc https://ourworldindata.org/coronavirus-data-explorer?zoomToS...
- Lewton 6y agoNo? Relative to Denmark and Norway, they’re doing as bad as ever? (X4-x8 amount of daily deaths per capita)
- albroland 6y agoCurrent daily deaths in Sweden are averaging about 4 per day continuing to trend towards 0, vs the 0 or 1 per day in Denmark or Norway. If you're trying to argue that 0.38 per capita vs 0.05 per capita is relevant when the gross numbers are so low I'm not sure what to tell you to convince you otherwise. Reference: https://ourworldindata.org/coronavirus-data-explorer?zoomToSelection=true&country=SWE~DNK~NOR&deathsMetric=true&interval=smoothed&smoothing=7&pickerMetric=location&pickerSort=asc https://ourworldindata.org/coronavirus-data-explorer?zoomToS... (graph basically looks identical between per capita or raw, pick your poison). I'm not sure how you make a meaningful statistical difference between them at this point when the numbers are approaching rounding errors.
- LordHumungous 6y agoHow can I get infected with one of those other Coronaviruses?
- __blockcipher__ 6y agoExchange bodily fluids with as many young people as possible. AFAIK there’s no way to be able to get voluntary exposure in a lab. Which is lame, imagine getting a precise dose of cultured $HCOV. OC43 has like a 9% nursing home fatality rate tho (which is kind of a hint that SARS-2 isn’t too special as far as mortality is concerned) Anyway if you have kids you have probably already been exposed to one of these CoVs at some point. The TL;DR is the more you do real life stuff the more likely you are to have exposure. Add it to the long list of externalities due to lockdown. Natural spread of pathogens is a good thing and not to be feared.
- known 6y agoI believe Antibody is better than Vaccine https://en.wikipedia.org/wiki/Antibody#/media/File:Antibody_Opsonization.svg https://en.wikipedia.org/wiki/Antibody#/media/File:Antibody_...
- peter_retief 6y agoDoes this imply that the COVID-19 virus will morph into the common cold virus?
- vibrio 6y agoNo. Mo more than a tiger will morph into a house cat.
- RalfWausE 6y agoWell, with a few hundred to thousand generations and a bit selective breeding i see no real problems here... just ask Fido about his wolf-great-great-great-(and so on)-grandfather ;-)
- vibrio 6y agoYes, many things are theoretically possible. In relative terms Coronavirus isnt that mutagenic. Every year for many years millions of people get seasonal coronaviruses there hasn’t been a “morph” (whatever that means). The SARS and SARS/CoV-2 crossovers did come from somewhere and it was bats which are REALLY good at being virus incubators. We are not. I guess in the environment we all are now in I’d prefer a message not be spread of a seasonal cold turning into a deadly respiratory disease based on such an apparently unlikely hypothetical. Or Let’s worry about things like swine and avian flus, which are orders of magnitude better at “morphing” yet much of the population still refuses to vaccinate annually.
- vibrio 6y agoJust realized I got the original morph direction wrong. Please pardon.
- peter_retief 6y agoThat is possible, also viruses can make bacteria deadly, check this https://www.sciencedaily.com/releases/2009/04/090417195827.htm https://www.sciencedaily.com/releases/2009/04/090417195827.h...
- rotterdamdev 6y agoIf vaccines do not give about 100 weeks of immunity, this thing is here to stay. Enjoy your lowered life expectancy.
- trenchgun 6y agoMisleading headline. From the article: > Based on these data, it is plausible to hypothesize that pre-existing cross-reactive HCoV CD4+ T cell memory in some donors could be a contributing factor to variations in COVID-19 patient disease outcomes, but this is at present highly speculative Also I recommend to read this: https://www.theatlantic.com/health/archive/2020/08/covid-19-immunity-is-the-pandemics-central-mystery/614956/ https://www.theatlantic.com/health/archive/2020/08/covid-19-...
- sradman 6y agoThe section Direct evidence of reactivity to HCoV epitopes homologous to SARS-CoV-2 epitopes [1]: > we designed a peptide pool encompassing peptides homologous to CD4-R30 epitopes, derived from HCoV-229E, HCoV-NL63, HCoV-OC43, HCoV-HKU1 and several other HCoVs (see Methods), for a total of 129 HCoV homologs (HCoV-R129; table S2). Similarly, we synthesized a pool that encompassed peptides homologous to the SARS-CoV-2 CD4-S31 epitope pool, consisting of potential epitopes derived from other HCoVs, for a total of 124 HCoV homologs (HCoV-S124; table S3). The "speculation" disclaimer, IMHO, is based on the assumption that the designed peptide pools invoke responses similar to their viral homologs. I have no issue with the "direct evidence" heading as this research makes an important step in demonstrating cross-reactivity. Teasing out the degree of protection this cross-reactivity provides in real-world populations is a much harder problem. [1] https://science.sciencemag.org/content/early/2020/08/04/science.abd3871#sec-4 https://science.sciencemag.org/content/early/2020/08/04/scie...
- DangerousPie 6y agoWhat's up with the editorialised title, which clearly overstates the conclusions of the paper?