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rafale

So as good as a vaccine basically?

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For protecting yourself, probably, for protecting others and helping prevent the virus from spreading and mutating, no.

Didn’t we establish last week the vaccine is not effective at stopping the spread of the virus?

It's not a binary yes-no question. It is still effective at stopping the spread of the virus, though not perfect.

It's not quite a binary yes-no question, but the vaccines not being effective enough for it to be possible to achieve herd immunity through vaccination alone makes a huge difference in how widely the virus ends up spreading.

What exactly you would consider "effective"?

This[1] study suggests that there a brief period of significant reduction (~three months), followed by a period modest to no risk reduction, followed by a period of increased risk.

This[2] study found no correlation between vaccination rates and viral spread.

[1] https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3949410

[2] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8481107/

The first study is clearly underpowered to say anything about the risk after more than around 150 days. This can be seen in figures 2 and S1, where the confidence intervals get larger than the effect size at around this point. Combining multiple age groups together also leads to a large risk of getting incorrect results due to Simpson's paradox [1]. But with so little data, the authors probably couldn't stratify for age groups without the confidence intervals exploding.

A much larger study from the US [2] shows no measurable decline in the protection against hospitalization due to COVID over more than 5 months after vaccination.

[1] https://www.covid-datascience.com/post/israeli-data-how-can-...

[2] https://doi.org/10.1016/S0140-6736(21)02183-8

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.

More or less yes. The initial narrative of the jab as panacea has since evolved. The talking point now focuses on reducing hospitalization and death. The bit about the jab stopping transmission has been dropped as the number of so called breakthrough cases increases. Press Secretary Jen Psaki comes to mind.

Stopping entirely, no. Reducing, yes.

Depends on how you define effective.

Forever? No. Perfectly? No.

They do have an measurable impact on transmission, especially soon after vaccination. https://www.nature.com/articles/d41586-021-02689-y

No.

The vaccines are not 100% effective at preventing spread (nor for preventing serious illness, for that matter).

That is not even remotely the same as "not effective".

In practice, the vaccines (with the possible partial exception of the J&J single dose) provide significant reduction in both spread and serious illness.

That vaccines reduce spread significantly is possible, and we can hope that they do, but it is not proven yet.

If everyone was vaccinated it would make a big difference.

People act astonished the COVID vaccines aren't perfect. You mentioning universal vaccination is such a key point. Let's look at smallpox.

We eliminated smallpox. Amazing! Yet, first, the smallpox vaccine wasn't perfect. It was 95% effective against infection. I would bet it's actually less than that. They probably mean symptomatic infection, because who was widely testing asymptomatic vaccinated people for smallpox? In contrast, symptomatic smallpox patients are pretty obviously and unambiguously infected with smallpox.

Second, what's particularly interesting is if you were the only smallpox-vaccinated person in a house of a couple others, the vaccine efficacy fell to about two thirds.

This isn't a world apart from the COVID vaccines. Two doses protects you 92-95% against severe disease. And two doses reduces the rate of transmission, if you end up infected, by 50% (this was 80%, pre Delta).

As I said, people act astonished the COVID vaccines aren't perfect. In reality, they're just focusing on COVID efficacy in ways they never have with other vaccines. The COVID vaccines are substantially more effective than your typical seasonal flu jag, or the BCG. COVID vaccines are not a world apart in efficacy than the Smallpox vaccine—and we beat smallpox! Smallpox elimination required universal vaccination, but we managed.

No: https://www.nbcnews.com/health/health-news/vaccinated-people...

I'm excited to hear the results of the pill among the vaccinated. Cutting the risk of severe symptoms among high-risk vaccinated people, and the risk of long covid for everyone is very important. The vaccines are great, but not silver bullets themselves.

Comparable individual outcome, worse societal outcome - you still spread it, so no reduction in overall cases, unlike a vaccine.

I thought the latest research was that the vaccinated can still spread COVID?

Some might, but not all, which is still a reduction

I encourage everyone eligible to get vaccinated if they can, but it does little to prevent spread. Over the long run we'll all be exposed no matter what we do. The real benefit of vaccines is in reducing the risk of severe symptoms.

https://www.nature.com/articles/d41586-021-02689-y

https://www.businessinsider.com/delta-variant-made-herd-immu...

I don't think either of those sources justifies "does little to prevent spread." The language used in them is considerably more hedged, eg:

"But growing evidence suggests that, with the Delta variant, fully vaccinated people can still transmit the virus."

And this:

"Unfortunately, the vaccine’s beneficial effect on Delta transmission waned to almost negligible levels over time. In people infected 2 weeks after receiving the vaccine developed by the University of Oxford and AstraZeneca, both in the UK, the chance that an unvaccinated close contact would test positive was 57%, but 3 months later, that chance rose to 67%. The latter figure is on par with the likelihood that an unvaccinated person will spread the virus."

Is also not super relevant— what most people want to know is not whether a breakthrough infection is capable of spreading it, but whether you're more likely to get a breakthrough infection. I think most vaccinated people (which is most people in rich countries now) care much more about the unvaccinated -> vaccinated transmission and the vaccinated -> vaccinated transmission than they do about vaccinated -> unvaccinated.

> it does little to prevent spread

How much, exactly?

> Over the long run we'll all be exposed no matter what we do

Plausible, but your sources don't appear to support that, other than the claim from Mr. Pollard. Is there anything I'm missing?

“The most statistically significant data point is that vaccinated people certainly have a faster rate of viral decline,” said Ferguson, “so they may potentially be infectious for less time, but they don’t necessarily have any reduced peak of viral load. Most transmission probably happens around that peak of viral load, which is why we think we’re still seeing substantial transmission rates from vaccinated people, both to unvaccinated people and to other vaccinated people.”

https://www.bmj.com/content/375/bmj.n2638

And yet your own linked study says, right in the first paragraph, that vaccinated contacts got it 38% less often.

Is it possible that this is not enough, and “virtually everyone will eventually be exposed”? Yes. Is it possible that COVID will become endemic and many (but not all or even most) people will be exposed? Yes. Have I seen any source that makes a strong case for this? Not yet.

> ...but it does little to prevent spread.

Actually it does reduce transmission

https://www.nbcnews.com/health/health-news/vaccinated-people...

Vaccination slightly reduces the risk of transmission for individual interactions (at least for a while) but that just stretches the curve out a little. Since SARS-CoV-2 is now endemic throughout the worldwide human population (plus several other mammal species) we can all expect to be exposed multiple times throughout our lives no matter what we do. Fortunately the vaccines are very effective at preventing deaths.

https://www.thelancet.com/journals/laninf/article/PIIS1473-3...

> Vaccination slightly reduces the risk of transmission for individual interactions (at least for a while) but that just stretches the curve out a little...

That's a disingenuous statement though because vaccines also help prevent getting infected in the first place, which reduces transmission. This study seems to focus on vaccinated people who had a breakthrough infection. If you read the 'Interpretation' section:

> Vaccination reduces the risk of delta variant infection and accelerates viral clearance. Nonetheless, fully vaccinated individuals with breakthrough infections have peak viral load similar to unvaccinated cases and can efficiently transmit infection in household settings, including to fully vaccinated contacts.

The first sentence implies vaccination reduces the risk of getting infection. The second sentence is talking about vaccinated people with a breakthrough infection having similar viral load. Therefore saying "Vaccination slightly reduces the risk of transmission for individual interactions" is untrue because it ignores the infection prevention mechanism of the vaccine. It's a lot better than 'slightly'

Yet, with the COVID vaccine, you still spread it, too:

https://theexpose.uk/wp-content/uploads/2021/09/Pierpont-Why...

https://www.cdc.gov/mmwr/volumes/70/wr/pdfs/mm7031e2-H.pdf

https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3897733

So, how could the outcome at the societal level be worse?

Do you have a source for R0 being _absolutely equal_ in vaccinated vs unvaccinated?

Give them time.

Time can also yield better vaccines, a policy of recurring vaccine doses (like the yearly flu shots), and milder variants that can emerge and become dominant, like some believe is what happened with the Spanish Flu.

While a vaccine is not 100% effective in preventing the spread of new cases it is at least somewhat effective.

Vaccine doesn't prevent spreading.

Citation needed - and note I didn't say it prevents "100% of spreading"

No: https://www.nbcnews.com/health/health-news/vaccinated-people...

Minus the preventative part.

Preventative of what?

Serious disease? - The same/similar (though studies have shown this declines within 6 months). Op is correct.

Catching/Transmission? - The current vaccines are systemic and not mucosal, so they don't stop it infecting the upper respiratory tract. - A recent study shows fully-vaccinated households can spread at similar rates to unvaccinated households [1]

[1] https://www.thelancet.com/journals/laninf/article/PIIS1473-3...

From your own link:

"Vaccination reduces the risk of delta variant infection and accelerates viral clearance."

They're apples and oranges, really. The best course of action to get a vaccine for the preventative effects and an antiviral if one has a breakthrough infection.

vaccines do not work if administered after infection -- this is after infection and symptoms.

Minus the high safety profile current vaccines exhibit.

as "good" as...as in...its effectiveness % reduces in line with the increase in profits?

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