Rochelle Walensky, the CDC director, has stated that vaccines do reduce severity, but they do not stop transmission. Assuming her words represent the scientific and expert opinion, could someone offer a coherent argument as to why there is so much pressure for others to get vaccinated? Is fear of the unvaccinated clogging up hospitals the primary motivation?
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stopping transmission is an impossibly high bar. Vaccines reduce transmission. Really really shockingly unexpectedly well for the first few months, in previous waves, but that sterilizing antibody-mediated immunity wanes. The booster restores that efficacy against transmission, but omicron's immune evasion means that even a booster only gets to ~70% efficacy against cases/transmission, compared to the surprise finding of ~95% efficacy for the first two doses. Fewer people spreading the virus -> fewer cases -> not as bad of a time.
The other important factor is that because your immune system is primed to recognize SARS-CoV-2 after vaccination, even if you do get infected, it responds and clears the infection more quickly than it would otherwise. That could mean you're never infectious, or infectious for fewer days, reducing transmission. Pre-omicron, breakthrough infections were infectious for 5.5 days on average, compared to 7.5 days for infections in unvaccinated people (https://www.nejm.org/doi/full/10.1056/NEJMc2102507). Yes, all this to maintain some semblance of healthcare for society, and to fill up fewer reefer trucks with body bags.
I don't believe that is accurate. Several studies show no significant difference between the viral load of vaccinated and unvaccinated. Here is one https://www.ucdavis.edu/health/covid-19/news/viral-loads-sim...
Also, recent reports from Denmark seem to indicate that vaccinated at best have equal protection against Omicron. Too early to declare this as fact, but the initial data actually favors a slight negative efficacy.
Confirmation bias is a tricky beast...
Even if Ct values are unchanged between vaccinated and unvaccinated cases, this is conditioned on being infected in the first place, and isn't the whole story. Duration of infectiousness matters.
Yes, boosters are necessary to reduce infection with Omicron, the antibodies from the original vaccine are just too big of a mismatch. That's not news. I'm glad to hear you're not taking those negative efficacy estimates at face value - it's almost certainly the result of missing confounders present at the start of their omicron wave. Unvaccinated individuals are probably less likely to live in urban areas, travel internationally, or even seek a covid test, for example.
Ct value is just a proxy to viral load and it has been found that the same Ct value results in less cultivable virus for vaccinated.
This negative effect is really most likely because of some confounding factors as others have said. I have seen claimed ADE as always but for that to be true I would expect recent vaccination to offer less protection not more and boosting offer less protection and not more.
Dropped the citation. https://www.nejm.org/doi/full/10.1056/NEJMc2102507
Thanks to the NBA for good time series data
Polio was stopped. Since we can't stop Covid in wild animals, and since severity is moderating, when do we plan to end Covid mandates?
Because you have misunderstood the statement.
Vaccines reduce infections considerably.
This is something the CDC has repeated over and over. From the CDC's website [1]:
"In October, the unvaccinated were 5x more likely to become infected."
Not only that - 'breakthrough infections' of the vaccinated are more likely to be less severe, and infection severity is correlated with shedding, meaning, even the 'vaxxed and infected' are less likely to spread.
Vaccines do not stop transmission, but they definitely reduce transmission and have a very material effect on R0.
In fact, by far the largest limiting factor on R0 are vaccines. Far more so than masks, for example.
If you think about it from a systematic perspective, the advantage is reducing transmission is the 'big advantage'.
If a giant wave of COVID wallops through the country and everyone gets it, a lot of people will die even those that are vaxxed. 'Flattening the Curve' is a very real thing. If you watch the % hospital beds occupied, it gets scary sometimes, in some places.
By reducing R0 - especially keeping it below 1 (i.e. not growing in the community) - means you reduce the likelihood that people will get it in the first place (and not take up hospital beds etc..).
Omicron has a bit different characteristics, but it's much the same story.
[1] https://covid.cdc.gov/covid-data-tracker/#rates-by-vaccine-s...
>Because you have misunderstood the statement.
“Our vaccines are working exceptionally well,” Walensky told CNN in an interview on Thursday, Aug. 5. “They continue to work well for Delta, with regard to severe illness and death – they prevent it. But what they can't do anymore is prevent transmission.”
I did not interpret her statement or misunderstand it. I quoted her directly.
Also, R0 with Omicron is on par with measles at 7-10, is it not?
R9 for measles is even higher - 10-12 but it has long incubation period that makes is much slower. Omicron is the fastest spreading virus in history so far.
> Is fear of the unvaccinated clogging up hospitals the primary motivation?
Yes? Hasn't it always been? Beds in ICUs are the main limiting factor of how much Covid we can handle. Lowering hospitalisations is great, that way it can end up as "just a bad flu" we have ( as in, a virus that's present, and spreading, and people get it, and some unfortunate people die from it, but doesn't grind whole countries to a stop).
that sounds revisionist to me. If that were the reason for (attempted) vaccine mandates then why do vaccine advocates feel the need to compel young, healthy people who have a vanishingly small chance of hospitalization to vaccinate? The story has always been about reducing spread.
Because those young people still have a chance to end up in the hospital, even if they're in great health ( as far as they know it). And it's not like a vaccine mandate can only apply for people in bad health - how would that even be decided? Erring on the side of caution seems to be a decent idea.
In your opinion, would you say that the vaccine program has been a success?
That's a rather vague question. I don't pretend to be an expert, but i do consider the vaccine rollout and management to be a success in the country i live in and have followed most closely - France. The global vaccine rollout is decent, but severely lacking in many poorer countries that should be helped.
There are two sides to the coin: susceptibility to infection, and infectiousness after infection.
Given that vaccination reduces disease severity, it seems likely that vaccination decreases your viral load after infection.
Therefore, though vaccination may not help much in preventing omicron infection, it will nevertheless reduce both disease severity and your infectiousness.