2. You linked to an old version that says "However, in July, the effectiveness against infection was considerably lower", in the current version the same sentence reads "In July, vaccine effectiveness against hospitalization has remained high"
The most important trend (IMHO) they point out is that effectiveness vs. severe disease does not drop or barely drops. They claim: To date, none of these studies has provided credible evidence of substantially declining protection against severe disease, even when there appear to be declines over time in vaccine efficacy against symptomatic disease.
However, the graph they provide doesn't seem to be based on data that appears reasonably chosen (that could be my limitaiton, sure).
They refer to appendices (which are here: https://www.thelancet.com/cms/10.1016/S0140-6736(21)02046-8/...), and specifically table S4 appears to be the basis for their graph D. In it, they split same-paper sources into early vs. late effectiveness with respect to hospitalization. Four sources are relevant.
- #5: Health IM of. Two dose vaccination data. 2021. 2021 - I can't find this source.
- #41 https://pubmed.ncbi.nlm.nih.gov/34401884/ - ...but this paper has huge error bars and additionally the average effectiveness jumps up and down just to underline that the source not only claims to be noisy but appears to be so too. There's just not enough clean data here for any conclusion (wrt to a declining efficacy vs. severe disease).
- #42 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8389393/ - this paper seems to have solid data, but it simply doesn't include data on when people were vaccinated, and it uses definitions like this: "Hospitalizations among persons with breakthrough infection were defined as new hospital admissions among persons fully vaccinated on the reporting day." - in other words, a mixture of people that are vaccine-protected, and those that have had the jab but not the time to become protected. And the paper does not track how long ago people were vaccinated - so how does the lancet article then try to split this into early vs. late groups? Presumably by calendar date, which I don't think is reasonable; at least not reasonable enough.
- #43 https://www.medrxiv.org/content/10.1101/2021.08.24.21262423v... - and I'm just going to believe they copied the results correctly, but notably that paper concludes: "The efficacy of the vaccine against severe disease for the 60+ age group also decreases; from 91% to 86% between those vaccinated four months to those vaccinated six months before the study. The corresponding efficacies for the 40-59 age group are 98% and 94%. Thus, the vaccine seems to be highly effective even after six months compared to the unvaccinated population, but its effectiveness is significantly lower than it was closer to the vaccination date."
So when they say this: "Given the data gaps, any wide deployment of boosters should be accompanied by a plan to gather reliable data about how well they are working and how safe they are. Their effectiveness and safety could, in some populations, be assessed most reliably during deployment via extremely large-scale randomisation,17 preferably of individuals rather than of groups." - that makes sense; I can understand that.
But this on the other hand: "To date, none of these studies has provided credible evidence of substantially declining protection against severe disease, even when there appear to be declines over time in vaccine efficacy against symptomatic disease." - seems to be contradicted by their own sources.
Given the data they themselves cite and in addition the many more sources demonstrating that protection from infection wanes (not just antibody levels), it seems implausible to assume that protection from severe disease won't wane significantly as well, even if they're right in saying we don't know for certain or by how much.
However, even the waning already demonstrated in the #43 data set represents approximately a 50% increase in the number of hospitalizations and an increase in transmissibility after less than 8 months. Saying it's "still very high" is surely true, but the way they paint boosters as somehow plausibly unnecessary smells like motivated reasoning to me.
They clearly make the case for greater third world vaccination; as an ethical argument that makes sense. But the claim that boosters likely won't be useful strikes me as being a little creative with their sources.
Furthermore, while the article goes to great lengths to question the utility of booster shots, it does not similarly make the case that avoiding booster shots will actually materially increase vaccinations elsewhere. And while that seems plausible at first glance, there are also reasons to think that's not really true: e.g. are the boosters going to be diverted from production or will they simply be usage of already distributed shots that weren't taken up by the vaccine hesitant (which could be logistically impossible to redistribute in time)? How many people will be both eligible and willing to take a booster, and how does that compare to the number of exported doses - it might not amount to much? Is the timing of the boosters early enough that there will still be a significant export crunch? Is there really a tradeoff here at all, or will by the time boosters are used in significant numbers (say 100 million) other production be ample too?
I don't think the article really makes a very thoughtful case, at all. It doesn't really support the notion that boosters will impact supply elsewhere by the time they're deployed, and it's claiming evidence supporting booster utility is slim, but it's not quite as slim as they make out, and again - by the time boosters are widely used, if the evidence we do have so far continues to build in that vein - there will be ample evidence then.
Sure, there is a plausible future in which boosters have unexpectedly low utility, yet high uptake, and are mostly doses from new production as opposed to older, already locally distributed doses, all while third-world vaccination remains highly supply constrained. That's a future to avoid. But the paper doesn't make the case it's a likely future, nor even that it'd be hard to see it coming and thus needs action today.
Peer review tells me that it's significantly less likely the researchers made mistakes handling the data, analyzing it, controlling for external causes, etc.
A peer-reviewed version also may change the wording of the abstract. The vaccine may be less effective on the South African variant than it is on the common strain, but if it's down to 85% from 95% we'll still do fine once a majority of people are immunized.
Super important to note that this is vaccine effectiveness against infection. It does not address the effectiveness of vaccines to prevent hospitalization or death.
The post is conflating vaccine efficacy and effectiveness which are two different epidemiological measures.
It also fails to consider the false positive and false negative rates inherent in these studies. In particular, lots of asymptomatic cases in the vaccinated arm are not caught by efficacy studies (false negatives). So claiming that low death rates are solely a result of reduced infection(as opposed to fighting off infections better) is also a conclusion made hastily.
Death rates and symptomatic cases are much measured much more accurately, and claiming that effectiveness studies have little point once there's vaccine efficacy is available underestimates the challenges of epidemiology.
But the overall point that statistics are hard to understand, easily misused in online arguments is a valid point.
Thanks for the link, but that study was very soon after the change and ignores the issue of whether vaccine effectiveness was the same (as history appears to be showing it was not). And that is the point. A small reduction of minor reported adverse effects for a large reduction of immunization effectiveness is usually not counted as a good trade-off by epidemiologists.
The vaccines reduce transmission but saying they are “very good” at this conflicts with basic logic, since that descriptor can’t be applied to both the efficacy in March (when it was very good) and the efficacy today, which we know is far less.
Key words here are "over the study duration" and "over the time period of the study". The study started in late July, so it's been about 4 months. The data that they examine probably lags a bit too and in the intervening period, cases have gone up significantly.
Over the course of a longer period of time and with cases on the rise as they are now, I'd expect the risk reduction to be much higher.
Edit: Also, these numbers are somewhat skewed by the fact that not all 40k people got the vaccine/placebo at once, but over a period of time.
For a significant time, the vaccine showed strong evidence of reducing hospitalization and fatality rates, esp for at risk populations. Did that change? I thought the main thing that changed was it stopped being effective at reducing transmission.
i'm curious to learn more about the discussion and criticism surrounding the 2nd link, if you'd be so kind as to share such resources
true, none of the other links are directly comparative to vaccine efficacy. my claim is in the context that _other_ studies show vaccine efficacy drops off after 6 months.
"vaccine effectiveness (VE) was 61% for two doses against COVID-19-associated hospitalizations; VE increased to between 85%–92% after receipt of a third/booster dose."
"COVID-19 vaccines remain our single most important tool to protect people against serious illness, hospitalization, and death."
>Reducing infections of family members by 40-50% is a massive effect
The point is that you're attributing this to vaccine effectiveness, when it may have been viral hygiene. The authors of the study did not attribute this reduction to the vaccine directly as you are.
77% efficacy against infection for Pfizer, 92% efficacy against infection for Moderna in the US.
Really wish people would stop saying vaccines have waned to uselessness. That just isn't even true for VE against infection. All the studies that I see at the lower level of ~50% VE against infection are highly problematic (there was a study of healthcare workers in San Diego where their unvaccinated control was only monitored via PCR for infection and only had a 3x increase of infections during the delta spike in Jul which suggests their unvaccinated controls had a significant amount of natural resistance or were taking many more precautions).
The measured outcomes in the initial vaccine trials were over 90% reduction in hospitalizations and deaths. That is what was known for sure at the time vaccines were rolled out. A reduction in transmission would have been a nice additional benefit, but the trials were not set up to measure if it had happened.
Since you got such a basic fact wrong, you might consider what else you've misunderstood and why. Then you can take steps to correct it.
The way I see it, both studies show effectively the same result with similar confidence intervals. The US study however covers a shorter timeframe.
As far as hospitalizations go, I am not arguing with that, vaccines clearly reduce disease burden. The question was: Are vaccines effective at stopping spread? Many countries are experiencing record infection rates with a large majority of the population vaccinated. This suggests to me that vaccines are not effective in that regard.
>...estimated 0% (not a typo) vaccine effectiveness against symptomatic infection after 20 weeks
That's also extremely misleading. The greatest vaccine benefit is not elimination of merely symptomatic infection, but to reduce serious symptoms (i.e. hospitalization) and death.
Here's what the study says about that:
Meanwhile, BNT162b2-induced protection against hospitalization and death appears to persist with hardly any waning for at least six months following the second dose.
2. You linked to an old version that says "However, in July, the effectiveness against infection was considerably lower", in the current version the same sentence reads "In July, vaccine effectiveness against hospitalization has remained high"
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