5 ms·

> I think the “vaccinated individuals can have high viral loads” line is particularly bad https://www.medrxiv.org/content/10.1101/2021.09.28.21264262v1 https:/

> I think the “vaccinated individuals can have high viral loads” line is particularly bad https://www.medrxiv.org/content/10.1101/2021.09.28.21264262v1 https://www.medrxiv.org/content/10.1101/2021.09.28.21264262v... https://www.ucdavis.edu/health/covid-19/news/viral-loads-similar-between-vaccinated-and-unvaccinated-people https://www.ucdavis.edu/health/covid-19/news/viral-loads-sim... How is a statement about what some researchers are finding "particularly bad"? If vaccinated individuals routinely have viral loads as high as those seen in unvaccinated individuals, it warrants more research into how the virus affects their bodies and what, if any, risks they might face both short term and long term. According to one study[1], vaccination reduces the risk of long COVID by 49%. Given that some studies have found the incidence of long COVID is in the double digit percentages[2], exploring this issue is not purely academic. It is pertinent to the hundreds of millions of vaccinated individuals who are still at risk of infection, even if their risk of hospitalization and death has been significantly reduced. Science works when we ask and investigate important questions. It doesn't work when we ignore these questions because we're afraid of the optics and how they might be misconstrued by some people. In fact, when it comes to COVID generally, it seems evident to me that shying away from difficult questions has had the opposite of the intended effect. It has probably caused more people to adopt anti-science views and reject beneficial measures like vaccination. [1] https://www.usnews.com/news/health-news/articles/2021-09-02/risk-of-long-covid-falls-by-half-in-breakthrough-cases https://www.usnews.com/news/health-news/articles/2021-09-02/... [2] https://www.medicalnewstoday.com/articles/more-than-one-third-of-covid-19-patients-may-experience-long-covid-symptoms https://www.medicalnewstoday.com/articles/more-than-one-thir...

space_fountain 5y ago
Welp, this is making me realize I was just wrong. My understanding of the science was something like you can find asymptomatic vaccinated individuals with similar viral loads to asymptomatic unvaccinated people, which is a bit meaningless when you're choosing a threshold for "infected" and when random chance will just see some people at any level. So to be clear it's not that I think the questions shouldn't be investigated, but a statement like "some vaccinated cases have high viral loads" is meaningless to explaining what my risk of spreading covid is. Trying to avoid the sort of bias that comes from trying to reinforce rather than question existing views, but I do still think the statement "No Significant Difference in Viral Load Between Vaccinated and Unvaccinated, Asymptomatic and Symptomatic Groups Infected with SARS-CoV-2 Delta Variant" despite being much more precise is still a bit unintuitive in it's implication. Because essentially what this means right is that they sampled people's viral loads, and then cut out everyone below a value they choose to mean "infected". It's still true that even if I had symptoms because I'm vaccinated my odds of having a high viral load are much lower. Presumably if you didn't remove all the samples with less than some concentration you'd see significant differences. I think that something the scientists got wrong consistently with covid was not unflinchingly communicating what was likely to be true mostly out of a fear that the public would take interventions that only moderately improved their safety like wearing a mask, and start doing riskier things or because of a bias towards doing nothing when clear evidence didn't exist. It can feel like similar things are happening with vaccination where it does seem pretty clear that getting vaccinated reduces your risk of passing on covid both because you're less likely to ever get a colony of the virus sufficient to count as "infected" and because you're likely to have a shorter infection.
- LurkingPenguin 5y ago
  > Because essentially what this means right is that they sampled people's viral loads, and then cut out everyone below a value they choose to mean "infected". Huh? Please cite the part of the study you're referring to to argue that the title of the study means the exact opposite of what it says. Every manufacturer of a PCR test specifies a Ct cutoff above which the result is considered false. > It's still true that even if I had symptoms because I'm vaccinated my odds of having a high viral load are much lower. Presumably if you didn't remove all the samples with less than some concentration you'd see significant differences. The study says the exact opposite: > There were no statistically significant differences in mean Ct-values of vaccinated (UeS: 23.1; HYT: 25.5) vs. unvaccinated (UeS: 23.4; HYT: 25.4) samples. In both vaccinated and unvaccinated, there was great variation among individuals, with Ct-values of <15 to >30 in both UeS and HYT data (Fig. 1A, 1B). Similarly, no statistically significant differences were found in the mean Ct-values of asymptomatic (UeS: 24.3; HYT: 25.4) vs. symptomatic (UeS: 22.7) samples, overall or stratified by vaccine status (Fig. 1B). Similar Ct-values were also found among different age groups, between genders, and vaccine types (Supplemental Figure 1).
  - space_fountain 5y ago
    > The study says the exact opposite: Maybe I'm misinterpreting the study. I interpreted that as being among the fraction of people who are infected both because that's what the title says, and because they say later that "75% of the positive samples were from unvaccinated individuals" which would seem to be inconsistent with the groups having similar viral loads. I thought we were dealing with a random variable composed something like this VIRAL_LOAD = INFECTED ? LOAD_FOR_INFECTED : LOAD_FOR_UNINFECTED And the study is saying that the random variable `LOAD_FOR_INFECTED` isn't correlated with vaccination status. That's indeed an interesting fact, but since `INFECTED` still was correlated (I think) overall for some random person `VIRAL_LOAD` would be too. Honestly a table would make all of this more clear.
    - LurkingPenguin 5y ago
      > Maybe I'm misinterpreting the study. With no offense intended, I think you're misunderstanding the whole concept of "viral load". If you are not infected with SARS-CoV-2, you don't have a SARS-CoV-2 "viral load".
spfzero 5y ago
I think partly what's going on is that some people have immune systems that have a hard time generating an effective response, whether or not they area vaccinated. Vaccination gives the immune system a chance to respond and memorize, as best it can. If it can't do that effectively, there is higher likelihood of a serious outcome.
- __blockcipher__ 5y ago
  I think this is very unlikely to significantly explain what we’ve seen. It’s much more likely just the natural result of artificial immunity waning much more rapidly than naturally acquired. As well as the fact that natural immunity involves exposure to the whole virus and therefore much broader types of epitopes for the immune system to “learn”.
  - walterbell 5y ago
    In addition, intramuscular vaccines only provide blood/serum antibodies, while nasal infection also provides nasal/mucosal antibodies. Those who recover from Covid infection gain sterilizing immunity (less than 1% will be reinfected) that stops future infections in the upper respiratory tract. That's why the CDC website says Covid (leaky, non-sterilizing) vaccines only provide protection (in blood) against serious illness, not infection (in nose). A future nasal vaccine may provide sterilizing immunity (what most people assume they are getting from a "vaccine", like their personal experience with the MMR vaccine).
    - space_fountain 5y ago
      I think these things are hard to be sure about, but there still is good evidence that covid vaccines are sterilizing in a lot of cases. The rate of infection is still lower for vaccinated people right when controlling for other demographics?
      - jaywalk 5y ago
        >there still is good evidence that covid vaccines are sterilizing in a lot of cases. What? No, there isn't. The Covid vaccines we have today are not sterilizing. Period. This isn't a conspiracy theory or anything like that, it's just a simple fact.

space_fountain 5y ago

Welp, this is making me realize I was just wrong. My understanding of the science was something like you can find asymptomatic vaccinated individuals with similar viral loads to asymptomatic unvaccinated people, which is a bit meaningless when you're choosing a threshold for "infected" and when random chance will just see some people at any level. So to be clear it's not that I think the questions shouldn't be investigated, but a statement like "some vaccinated cases have high viral loads" is meaningless to explaining what my risk of spreading covid is. Trying to avoid the sort of bias that comes from trying to reinforce rather than question existing views, but I do still think the statement "No Significant Difference in Viral Load Between Vaccinated and Unvaccinated, Asymptomatic and Symptomatic Groups Infected with SARS-CoV-2 Delta Variant" despite being much more precise is still a bit unintuitive in it's implication. Because essentially what this means right is that they sampled people's viral loads, and then cut out everyone below a value they choose to mean "infected". It's still true that even if I had symptoms because I'm vaccinated my odds of having a high viral load are much lower. Presumably if you didn't remove all the samples with less than some concentration you'd see significant differences. I think that something the scientists got wrong consistently with covid was not unflinchingly communicating what was likely to be true mostly out of a fear that the public would take interventions that only moderately improved their safety like wearing a mask, and start doing riskier things or because of a bias towards doing nothing when clear evidence didn't exist. It can feel like similar things are happening with vaccination where it does seem pretty clear that getting vaccinated reduces your risk of passing on covid both because you're less likely to ever get a colony of the virus sufficient to count as "infected" and because you're likely to have a shorter infection.

LurkingPenguin 5y ago
> Because essentially what this means right is that they sampled people's viral loads, and then cut out everyone below a value they choose to mean "infected". Huh? Please cite the part of the study you're referring to to argue that the title of the study means the exact opposite of what it says. Every manufacturer of a PCR test specifies a Ct cutoff above which the result is considered false. > It's still true that even if I had symptoms because I'm vaccinated my odds of having a high viral load are much lower. Presumably if you didn't remove all the samples with less than some concentration you'd see significant differences. The study says the exact opposite: > There were no statistically significant differences in mean Ct-values of vaccinated (UeS: 23.1; HYT: 25.5) vs. unvaccinated (UeS: 23.4; HYT: 25.4) samples. In both vaccinated and unvaccinated, there was great variation among individuals, with Ct-values of <15 to >30 in both UeS and HYT data (Fig. 1A, 1B). Similarly, no statistically significant differences were found in the mean Ct-values of asymptomatic (UeS: 24.3; HYT: 25.4) vs. symptomatic (UeS: 22.7) samples, overall or stratified by vaccine status (Fig. 1B). Similar Ct-values were also found among different age groups, between genders, and vaccine types (Supplemental Figure 1).
- space_fountain 5y ago
  > The study says the exact opposite: Maybe I'm misinterpreting the study. I interpreted that as being among the fraction of people who are infected both because that's what the title says, and because they say later that "75% of the positive samples were from unvaccinated individuals" which would seem to be inconsistent with the groups having similar viral loads. I thought we were dealing with a random variable composed something like this VIRAL_LOAD = INFECTED ? LOAD_FOR_INFECTED : LOAD_FOR_UNINFECTED And the study is saying that the random variable `LOAD_FOR_INFECTED` isn't correlated with vaccination status. That's indeed an interesting fact, but since `INFECTED` still was correlated (I think) overall for some random person `VIRAL_LOAD` would be too. Honestly a table would make all of this more clear.
  - LurkingPenguin 5y ago
    > Maybe I'm misinterpreting the study. With no offense intended, I think you're misunderstanding the whole concept of "viral load". If you are not infected with SARS-CoV-2, you don't have a SARS-CoV-2 "viral load".

spfzero 5y ago

I think partly what's going on is that some people have immune systems that have a hard time generating an effective response, whether or not they area vaccinated. Vaccination gives the immune system a chance to respond and memorize, as best it can. If it can't do that effectively, there is higher likelihood of a serious outcome.

__blockcipher__ 5y ago
I think this is very unlikely to significantly explain what we’ve seen. It’s much more likely just the natural result of artificial immunity waning much more rapidly than naturally acquired. As well as the fact that natural immunity involves exposure to the whole virus and therefore much broader types of epitopes for the immune system to “learn”.
- walterbell 5y ago
  In addition, intramuscular vaccines only provide blood/serum antibodies, while nasal infection also provides nasal/mucosal antibodies. Those who recover from Covid infection gain sterilizing immunity (less than 1% will be reinfected) that stops future infections in the upper respiratory tract. That's why the CDC website says Covid (leaky, non-sterilizing) vaccines only provide protection (in blood) against serious illness, not infection (in nose). A future nasal vaccine may provide sterilizing immunity (what most people assume they are getting from a "vaccine", like their personal experience with the MMR vaccine).
  - space_fountain 5y ago
    I think these things are hard to be sure about, but there still is good evidence that covid vaccines are sterilizing in a lot of cases. The rate of infection is still lower for vaccinated people right when controlling for other demographics?
    - jaywalk 5y ago
      >there still is good evidence that covid vaccines are sterilizing in a lot of cases. What? No, there isn't. The Covid vaccines we have today are not sterilizing. Period. This isn't a conspiracy theory or anything like that, it's just a simple fact.