4 ms·

Oh man, that is severely splitting hairs. You can't have T-cells and antibodies covering every single potential surface area of every cell of every tissue in t

Oh man, that is severely splitting hairs. You can't have T-cells and antibodies covering every single potential surface area of every cell of every tissue in the body, so there can be places that are infected in the body even though you're totally subclinical and not shedding in a meaningful sense. But such a small infection that is effectively managed by a vaccine-primed immune system is meaningless. That's like saying that a clean living-room floor isn't really clean because you can spot a speck of dust with your magnifying glass. For all intents and purposes, vaccines prevent people from contracting an infection that is clinically meaningful, and that can be spread to others in a way that leads to infection. That's herd immunity. "Herd immunity is a form of indirect protection from infectious disease that occurs when a sufficient percentage of a population has become immune to an infection, whether through vaccination or previous infections, thereby reducing the likelihood of infection for individuals who lack immunity." https://en.wikipedia.org/wiki/Herd_immunity https://en.wikipedia.org/wiki/Herd_immunity You're making it sound like vaccinated people are walking around shedding virus all over the place, but simply showing no outward signs.

acqq 6y ago
> You can't have T-cells and antibodies covering every single potential surface area of every cell of every tissue in the body, so there can be places that are infected in the body even though you're totally subclinical That is exactly the mechanism how non-sterilizing protection by vaccines for respiratory diseases occurs: the cells in mucosa in the upper respiratory tract are infected every time one is exposed to the virus before the antibodies can respond. The mucosal cells shed the virus even if the infection doesn't have to result in symptoms. The viral shedding is however high enough to allow transmission to the unprotected. Note that at this very moment there are still no reports of a vaccine inducing sterilizing immunity, especially in nasal mucosa. Up to now, for the vaccines which reported the efficacy, it was by design measured and reported as protection to the symptoms of the disease. The press releases take care to mention "efficacy according to the primary study objective", where just "protection from Covid-19" (as in: from the disease with defined symptoms) was reported. Not the sterilizing immunity. (2) And, specifically for Covid-19: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31976-0/fulltext https://www.thelancet.com/journals/lancet/article/PIIS0140-6... "Challenge studies in vaccinated primates showed reductions in pathology, symptoms, and viral load in the lower respiratory tract but failed to elicit sterilising immunity in the upper airways." (1) "These observations suggest that we cannot assume COVID-19 vaccines, even if shown to be effective in reducing severity of disease, will reduce virus transmission to a comparable degree. The notion that COVID-19-vaccine-induced population immunity will allow a return to pre-COVID-19 “normalcy” might be based on illusory assumptions." "Crucially, it will be important to communicate to policy makers and the general public that first-generation vaccines are only one tool in the overall public health response to COVID-19 and unlikely to be the ultimate solution that many expect." (Note: All cited here are the papers directly studying Covid-19, which are far more relevant in this case than a wikipedia article about what "herd immunity" were, when and if it exists.) 1) See https://www.nejm.org/doi/10.1056/NEJMoa2024671 https://www.nejm.org/doi/10.1056/NEJMoa2024671 and Figure 3 and https://www.nature.com/articles/s41586-020-2608-y https://www.nature.com/articles/s41586-020-2608-y "Viral gRNA was detected in nose swabs from all animals and no difference was found on any day between vaccinated and control animals." 2) See also my other posts here, e.g. the one which directly cites the Moderna protocol. https://news.ycombinator.com/item?id=25286838 https://news.ycombinator.com/item?id=25286838
- phobosanomaly 6y ago
  So, are you saying that meaningful (not perfect) herd immunity is impossible for any respiratory viral infection, even in the presence of a vaccine that generates a robust T and B cell response? Also, regarding the nasal swabs in those monkeys in the nature paper, you're not spraying respiratory droplets all over the place out of your nose when you vocalize. It's coming out of your trachea and oropharynx as those vocal cords vibrate and air gets pushed out of the lower airway. You don't sneeze at the grocery store cashier whether you want paper or plastic. "We observed a significantly reduced viral load in the bronchoalveolar lavage fluid and lower respiratory tract tissue of vaccinated rhesus macaques that were challenged with SARS-CoV-2 compared with control animals" That's a HUGE win in reducing transmission. Come on, you gotta be a little more enthusiastic here! These vaccines getting out there are going to have a MASSIVE impact on knocking down this pandemic.
  - acqq 6y ago
    The vaccines will reduce the visible effects of pandemic, that's sure, by reducing the numbers of those who will have to be admitted to the hospital. In Covid-19 a huge percentage of people who get infected currently have to be hospitalized, and reducing that number will help a lot. What we still can't expect, until we have some different and exact information, is to be able to visit our non-vaccinated or immune suppressed relatives and friends without a mask and be really sure that we can't infect them as long as the incidence is high enough. What we currently know says the opposite: no proof of sterilizing immunity by the current vaccines, and animal studies which show the same viral load in upper respiratory tract mucosa. That's what I personally worry about, I have such people and I don't want them to die because of the, at the moment still unfounded, belief of some (like "phobosanomaly" who uses totally irrelevant quotations to support their claims) that the vaccine must have "sterilizing immunity" while the experts are cautions to point that the currently available information surely doesn't support that. And if "phobosanomaly" now also doesn't claim at the moment that the vaccines have such property but merely that the transmission will be "reduced" then I don't disagree with that. But for me "transmission will be reduced" as this moment still means "we can't even assume that the vulnerable can't become infected from those who already received the vaccine." Also note that the distribution of those who get the vaccine but then still become ill (1 of 20 by Pfizer and Moderna trials) will also not be evenly distributed across the population. That means that if you know even less vulnerable people, you can expect that some of them won't be protected even if they can and do receive the vaccine. I worry also for those. If you also maybe believe that the vulnerable are disposable because they are old and not productive anymore or something like that, I can assure you that I personally know young and worthy people who can still contribute a lot to the world but who can surely be considered vulnerable, and who surely aren't doing anything wrong, who aren't overweight and who are doing sports regularly. And finally, I admit I also worry for those who I know who are considered "older" but whose number of days on this planet can also be seriously affected by the attitudes of those who want to believe only that what is convenient to them, even if it is completely opposite of what is currently known.

acqq 6y ago

> You can't have T-cells and antibodies covering every single potential surface area of every cell of every tissue in the body, so there can be places that are infected in the body even though you're totally subclinical That is exactly the mechanism how non-sterilizing protection by vaccines for respiratory diseases occurs: the cells in mucosa in the upper respiratory tract are infected every time one is exposed to the virus before the antibodies can respond. The mucosal cells shed the virus even if the infection doesn't have to result in symptoms. The viral shedding is however high enough to allow transmission to the unprotected. Note that at this very moment there are still no reports of a vaccine inducing sterilizing immunity, especially in nasal mucosa. Up to now, for the vaccines which reported the efficacy, it was by design measured and reported as protection to the symptoms of the disease. The press releases take care to mention "efficacy according to the primary study objective", where just "protection from Covid-19" (as in: from the disease with defined symptoms) was reported. Not the sterilizing immunity. (2) And, specifically for Covid-19: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(20)31976-0/fulltext https://www.thelancet.com/journals/lancet/article/PIIS0140-6... "Challenge studies in vaccinated primates showed reductions in pathology, symptoms, and viral load in the lower respiratory tract but failed to elicit sterilising immunity in the upper airways." (1) "These observations suggest that we cannot assume COVID-19 vaccines, even if shown to be effective in reducing severity of disease, will reduce virus transmission to a comparable degree. The notion that COVID-19-vaccine-induced population immunity will allow a return to pre-COVID-19 “normalcy” might be based on illusory assumptions." "Crucially, it will be important to communicate to policy makers and the general public that first-generation vaccines are only one tool in the overall public health response to COVID-19 and unlikely to be the ultimate solution that many expect." (Note: All cited here are the papers directly studying Covid-19, which are far more relevant in this case than a wikipedia article about what "herd immunity" were, when and if it exists.) 1) See https://www.nejm.org/doi/10.1056/NEJMoa2024671 https://www.nejm.org/doi/10.1056/NEJMoa2024671 and Figure 3 and https://www.nature.com/articles/s41586-020-2608-y https://www.nature.com/articles/s41586-020-2608-y "Viral gRNA was detected in nose swabs from all animals and no difference was found on any day between vaccinated and control animals." 2) See also my other posts here, e.g. the one which directly cites the Moderna protocol. https://news.ycombinator.com/item?id=25286838 https://news.ycombinator.com/item?id=25286838

phobosanomaly 6y ago
So, are you saying that meaningful (not perfect) herd immunity is impossible for any respiratory viral infection, even in the presence of a vaccine that generates a robust T and B cell response? Also, regarding the nasal swabs in those monkeys in the nature paper, you're not spraying respiratory droplets all over the place out of your nose when you vocalize. It's coming out of your trachea and oropharynx as those vocal cords vibrate and air gets pushed out of the lower airway. You don't sneeze at the grocery store cashier whether you want paper or plastic. "We observed a significantly reduced viral load in the bronchoalveolar lavage fluid and lower respiratory tract tissue of vaccinated rhesus macaques that were challenged with SARS-CoV-2 compared with control animals" That's a HUGE win in reducing transmission. Come on, you gotta be a little more enthusiastic here! These vaccines getting out there are going to have a MASSIVE impact on knocking down this pandemic.
- acqq 6y ago
  The vaccines will reduce the visible effects of pandemic, that's sure, by reducing the numbers of those who will have to be admitted to the hospital. In Covid-19 a huge percentage of people who get infected currently have to be hospitalized, and reducing that number will help a lot. What we still can't expect, until we have some different and exact information, is to be able to visit our non-vaccinated or immune suppressed relatives and friends without a mask and be really sure that we can't infect them as long as the incidence is high enough. What we currently know says the opposite: no proof of sterilizing immunity by the current vaccines, and animal studies which show the same viral load in upper respiratory tract mucosa. That's what I personally worry about, I have such people and I don't want them to die because of the, at the moment still unfounded, belief of some (like "phobosanomaly" who uses totally irrelevant quotations to support their claims) that the vaccine must have "sterilizing immunity" while the experts are cautions to point that the currently available information surely doesn't support that. And if "phobosanomaly" now also doesn't claim at the moment that the vaccines have such property but merely that the transmission will be "reduced" then I don't disagree with that. But for me "transmission will be reduced" as this moment still means "we can't even assume that the vulnerable can't become infected from those who already received the vaccine." Also note that the distribution of those who get the vaccine but then still become ill (1 of 20 by Pfizer and Moderna trials) will also not be evenly distributed across the population. That means that if you know even less vulnerable people, you can expect that some of them won't be protected even if they can and do receive the vaccine. I worry also for those. If you also maybe believe that the vulnerable are disposable because they are old and not productive anymore or something like that, I can assure you that I personally know young and worthy people who can still contribute a lot to the world but who can surely be considered vulnerable, and who surely aren't doing anything wrong, who aren't overweight and who are doing sports regularly. And finally, I admit I also worry for those who I know who are considered "older" but whose number of days on this planet can also be seriously affected by the attitudes of those who want to believe only that what is convenient to them, even if it is completely opposite of what is currently known.