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Oxford vaccine shows sustained protection of 76% in 3-month gap til second dose

ox.ac.uk

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Re: Oxford vaccine shows sustained protection of 76% in 3-month gap til second dose

#161

Post by Jolter »

password321 wrote: post #58

Strangely, this news went under the radar: https://www.bmj.com/content/372/bmj.n149 23 deaths in Norway, possibly from vaccine.

Well, to begin with it’s off topic for this thread.

But anyway, “frail elderly patients” have a tendency to have a short life expectancy whether there is a pandemic on or not. The thing they will have to sort out is whether those 23 are coincidental or not. Ie what number would we have expected to die, had we not vaccinated them. This is pretty elementary statistics and I expect that they’ll sort it out shortly.

Re: Oxford vaccine shows sustained protection of 76% in 3-month gap til second dose

#162

Post by snystrom »

xvedejas wrote: post #134
snystrom wrote: post #133

Earlier quoted context omitted.

A strong argument against this is the potential to apply selective pressure for virus variants that escape antibody binding. After the first vaccine dose, antibody titer in the blood is lower than it would be after 2 doses. Some of the new variants are better at escaping antibody binding, but with high enough antibody titer in the blood, they can still be cleared. Using only 1 dose risks not having enough antibody to…

It will be a strong argument when there's more evidence. Do we have any example of significantly stronger viral adaptation in the presence of a vaccine that successfully stimulates the immune system? Even a full course of the less-effective vaccines would still be risking this. The AstraZeneca and Sinovac vaccines only have an efficacy of around 70% after all.

You're correct that there's never been an experiment on the scale of the current pandemic, but there is a long history of demonstrating that viruses rapidly evolve to escape antibodies, and that this effect is enhanced under direct selective pressure.

Late 2020 there was a paper published where they demonstrate this effect for SARS-Cov-2 in human cells, then they look for those variants in humans and find that they were already infecting humans, demonstrating this selection activity happens in the wild [1]. I totally hear you about the 1 does vaccine argument. I think the kicker is two-fold. First, we do not know whether vaccinated individuals can still be infected with and spread COVID. Second is the rollout is currently very slow. You could imagine a scenario where enough folks are vaccinated to add pressure, but not reduce widespread transmission. If the data comes out that you can't transmit covid after the first dose (and I believe that Moderna has this data, but not ready to publish), I think the answer is clear to delay the second dose. But I think it is the absence of the transmission data, not whether evolution will happen to the virus, is part of the reasoning for the current strategy of completing the vaccination course in the ~3 week timeline.

[1] https://elifesciences.org/articles/61312

Re: Oxford vaccine shows sustained protection of 76% in 3-month gap til second dose

#163

Post by tinus_hn »

makomk wrote: post #114
chrisseaton wrote: post #112

Earlier quoted context omitted.

> It can be a challenge to see how the UK government could have dealt with this worse. For example they could have delayed ordering vaccines, like the Europeans have.

The vaccine screw-up wasn't even the only... interesting part of the European pandemic response. For example, there was a very public push by the EU itself as an institution for member states to reopen travel in order to save the critically important summer vacation season that was just quietly forgotten about by the media after it turned out to be a terrible idea. Complete with a certain amount of pressure on the UK…

That sounds pretty logical but it isn’t. Without travel it would have been a slower motion train wreck. Still a train wreck, but now with even more economic destruction.

Re: Oxford vaccine shows sustained protection of 76% in 3-month gap til second dose

#164

Post by dragontamer »

rich_sasha wrote: post #159
dragontamer wrote: post #141

Earlier quoted context omitted.

> The first dose prevents hospitalization. Right now, for every second dose we give, that's a decision to deny someone a life-saving dose in favor of someone already protected. What a strange prioritization to make. Does 1 dose prevent the spread of COVID19? If it requires 2-doses to get a true "efficacy" (lower spread), then it might be more worthwhile to push 2-doses, rather than 1-dose (where everyone gets "less s…

As for whether 1 dose prevents spreading: for many countries, in particular UK, the current bottleneck is hospital occupancy, and that is overwhelmingly people over 70 - something like 60% IIRC. If 1 dose, followed by a 2nd some time, can cut that number down a lot (some people won't get Covid, and few will get a bad one), hospitals can be freed and start returning to their usual work - cancer treatments etc. That's…

> As for whether 1 dose prevents spreading: for many countries, in particular UK, the current bottleneck is hospital occupancy, and that is overwhelmingly people over 70 - something like 60% IIRC.

Preventing the spread of COVID19 has an exponential effect on all stats.

If 1-dose only reduces the symptoms (but continues the exponential spread), then 20% vaccination rate means that you have 20% fewer hospitalizations after a month.

-----------

In contrast, if 2-dose prevents the spread, then 10% vaccination means 10% fewer spread *PER GENERATION* of COVID19.

That's 90% of the hospitalizations in one generation (~1-week period). After 2-weeks, you have ~81% hospitalizations. After 3-weeks, down to 73%. After 4 weeks, only 65%.

Controlling the spread is the #1 health priority that has exponential effects. I'd take 1/2 the vaccination rate if we have a better chance at tackling the exponential-spread issue.

Re: Oxford vaccine shows sustained protection of 76% in 3-month gap til second dose

#165

Post by bluGill »

fy20 wrote: post #156
bluGill wrote: post #44

Earlier quoted context omitted.

Note that deaths are very lagging. It can be a couple months between being exposed to COVID and death, maybe even more as medical science has learned about treating COVID over time. It is reasonable to assume that everyone dieing today got COVID before there was a vaccine, though there have been a few deaths by now that could have been prevented if the first vaccines were not given to someone else (if that person who…

The UK only treats deaths within 28 days of a positive test as a 'COVID death'.

Interesting. I know that in my community the spike in covid deaths lags the new positive count by almost 2 months. I'm not sure how they decide something is a COVID death, I just watch the daily new positive and daily deaths numbers.

Re: Oxford vaccine shows sustained protection of 76% in 3-month gap til second dose

#166

Post by alistairSH »

mchusma wrote: post #91
alistairSH wrote: post #31

Earlier quoted context omitted.

Astra Zeneca bungled their FDA trials in 2020. They went from being one of the most promising vaccines to an also-ran. https://www.nytimes.com/2020/12/08/business/covid-vaccine-ox...

This is basically a hit piece, and this type of journalism really hurts us because it misses the big picture. The reality is that Astrazeca ran full trials which proved safety and efficacy in peer reviewed journals. Were things a bit messy? Yes! Its a pandemic, things didn't go perfectly. But is there any scientifically based reason to believe that the vaccine is not safe and effective against death? Their studies ca…

Uh, they completely botched the dosing in during the trial. Not just a little, but off by 50%. Then results weren't as expected (those on lower dose fared better) and they had no explanation.

That's not a "full trial which proved safety and efficacy".

Re: Oxford vaccine shows sustained protection of 76% in 3-month gap til second dose

#167

Post by heavenlyblue »

chrisseaton wrote: post #112
harry8 wrote: post #94

Earlier quoted context omitted.

Here's another way of framing it: Having messed this up so very badly doing idiotically risky things from the start the latest big risk taken by the UK government didn't actually backfire as badly as the previous ones. Others have pointed at the current per-capita deaths. This completely ignores the long-term effects to survivors accross the population. It can be a challenge to see how the UK government could have de…

> It can be a challenge to see how the UK government could have dealt with this worse. For example they could have delayed ordering vaccines, like the Europeans have.

I find it amusing that now every single UK conservative is defending the UK government with this specific point when the UK government managed to have a series of regular fuckups over the last year nobody else managed to get in the EU.

Re: Oxford vaccine shows sustained protection of 76% in 3-month gap til second dose

#168

Post by heavenlyblue »

makomk wrote: post #114
chrisseaton wrote: post #112

Earlier quoted context omitted.

> It can be a challenge to see how the UK government could have dealt with this worse. For example they could have delayed ordering vaccines, like the Europeans have.

The vaccine screw-up wasn't even the only... interesting part of the European pandemic response. For example, there was a very public push by the EU itself as an institution for member states to reopen travel in order to save the critically important summer vacation season that was just quietly forgotten about by the media after it turned out to be a terrible idea. Complete with a certain amount of pressure on the UK…

> Complete with a certain amount of pressure on the UK government to try and get them to go along with it too.

And it took all the way to December to implement testing at the borders for the UK government while they were obviously allowing their citizens to take advantage of those travel policies.

Re: Oxford vaccine shows sustained protection of 76% in 3-month gap til second dose

#169

Post by caffeine »

neilsense wrote: post #153
caffeine wrote: post #29

Earlier quoted context omitted.

My perception of the Oxford/AstraZeneca vaccine is that their credibility is compromised. I take claims of its efficacy with a similar dose of salt to claims about the Russian and Chinese vaccines. Reason is that early on they were rushing data and approvals on grounds of national pride, in a very similar way to the Chinese and Russian authorities. Pfizer and Moderna seem to have been more thorough.

What you're saying makes no sense. Comparing the UK to China/Russia based on what? We have some of the best research and industrial pharma in the world and we don't hold scientists hostage if they say the wrong things. What an absolutely ridiculous statement to make. I can only believe you are trolling in some way, or have you own nationalist pride over Pfizer/Moderna.

They never did a proper phase 3 trial. Instead they did two half-trials, with different doses.

Initially they pretended this was done on purpose, and claimed 90% efficacy:

https://www.bbc.com/news/health-55040635

Later it came out this was an accident and cover-up, spun as a lucky discovery:

https://www.wired.com/story/the-astrazeneca-covid-vaccine-da...

https://www.reuters.com/article/us-health-coronavirus-astraz...

Even now, the lower bound of 95% C.I. around efficacy with two doses is 63% which is quite low, relative to the headlines:

https://www.ox.ac.uk/news/2021-02-02-oxford-coronavirus-vacc...

I'm not a troll, just a critic of a lab and a U.K. government that fudged some data because they needed a PR win.

https://www.bloomberg.com/news/features/2020-07-15/oxford-s-...

"I hope we can improve on those timelines and come to your rescue.” - Sarah Gilbert

That kind of hubris made it hard to admit process errors and low efficacy rates.

Re: Oxford vaccine shows sustained protection of 76% in 3-month gap til second dose

#170

Post by heavenlyblue »

thu2111 wrote: post #158
harry8 wrote: post #94

Earlier quoted context omitted.

Here's another way of framing it: Having messed this up so very badly doing idiotically risky things from the start the latest big risk taken by the UK government didn't actually backfire as badly as the previous ones. Others have pointed at the current per-capita deaths. This completely ignores the long-term effects to survivors accross the population. It can be a challenge to see how the UK government could have de…

I feel I just looked into a mirror world that's exactly like the one I live in, except everything is reversed. The UK started out very briefly with a Sweden-like strategy. We now know the Sweden strategy was correct: their results are in line with the EU average[1] despite a drastically smaller decline in GDP, a much smaller backlog of non-COVID health care problems and of course, a critically higher freedom and qual…

Your [1] literally is showing that Sweden's numbers are double European's over the course of the whole of summer.
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