Please don't let it be true that one dose of Pfizer jab is only 33% effectuve

[Calmandmeasured1]

www.thesun.co.uk/news/13795481/one-dose-vaccine-only-33-effective-israeli-experts-claim/

@FourTeaFallOut

"Sir Patrick, the Government's chief scientific adviser, said experts would need to "keep measuring the numbers" but added that better immunity would build over time.

Speaking to Sky News, he said: "We need to look at this very carefully. What we know from clinical studies… is that if you take everything from day zero to day 28, then the overall figure is something like 50 per cent protection.

"But of course you don't expect any protection in the first days because your immune system hasn't had a chance to build up and some people may have been infected before they had the vaccine. If you take it from day 10 up to day 21 and beyond, it looks much more like the 89 per cent figure the JCVI gave."

Quoted for those that missed this, because it's important.

q: How effective is one dose?
a: It completely depends on how many days have elapsed.

q. I heard 33%, is that the best we can expect from a single dose?
a. nope. The authors of that statistic haven't even released a preprint of their methodology yet. They are saying that 14 days after a jab they saw a 33% reduction in positivity, which was their particular metric. There are others that might be more meaningful. Like hospitalisations for example.

www.sciencemediacentre.org/expert-reaction-to-media-reports-of-study-results-from-israel-and-comments-made-by-prof-nachman-ash-israels-coronavirus-tsar-about-the-efficacy-of-a-single-dose-of-the-pfizer-vaccine/

If I average efficacy over the first 10 minutes after your jab, it'll definitely be 0%. If I average efficacy over the first week, it will look rubbish. If I average it over two weeks, it will be better, but still look measly, even if it were 100% effective after two weeks, because that's still an average and includes all the days when the vaccine hasn't even begun to make any difference. Did the Israeli study use an average? It's not clear because they haven't published yet.

What really matters is what does the efficacy look like after 2-3 weeks. And after 4 weeks. And 5.

We'll know the answers soon.

A 33 % efficacy is still better than no vaccine at all.

I believe the original guidance by Pfizer said 90% protection from 'severe' Covid, presumably hospitalisation. On the other hand I understand the Israel data only looked at those confirmed to have come down with Covid, some may be ill, some hardly at all but hopefully none were severely so.

That is to say, 80-90% protection from severe Covid after one dose.

Pfizer said two doses 3 weeks apart to have 90% + immunity.

Not one dose 12 weeks apart, if one dose gave v high immunity, they'd have settled for that.

I am amazed that the Govt decided, with zero trials & based on completely different vaccines, to have a 12 week gap.

I think in Israel they compared 200,000 who had first Pfizer jab with 200,000 people who had not had it and after 8-10 days they saw a distinct reduction in illness in the vaccinated group of 33% (presume this does not necessarily take into account differences in severity, but just positive test?) This is different to the trial data (86%) but in real world conditions it was expected to be. (Also, aren't they squeezing six doses from their Pfizer vials rather than five?) They also said that they understand the uk govt decision to space the vaccinations out to prioritise covering more people because we are in an emergency.

@jasjas1973

Pfizer said two doses 3 weeks apart to have 90% + immunity.

Not one dose 12 weeks apart, if one dose gave v high immunity, they'd have settled for that.

I am amazed that the Govt decided, with zero trials & based on completely different vaccines, to have a 12 week gap.

Me too.

Made some sense with the AZ vaccine, but it works differently.

The Sun?

Top scientists and medics agreed the 12 week delay as safe.

Benjispruce2 Some did. But others didn't. Which ones should we believe?

It's not about the Sun as a source; it was also in the BBC or Guardian this morning as I read about it on one of those pages. It's about what Israel is finding having gone this route of a single initial dose to vaccinate as many as possible quickly. Our government is disputing it's as low as that, but admitting it is likely lower than the 89% protection they were hoping for.

we're all getting 2 doses anyway? That was always the plan.

the sample size in Israel is too small to be significant - true efficacy/efficiency rates won't be clear for some time

I'm no defender of this government but it wasn't them that made the 12 weeks decision. It was the MHRA, completely independent of the government but with a view to the state of NHS ability to provide the vaccine.

Pfizer FDA guidance notes said: "...efficacy in preventing confirmed COVID-19 occurring at least 7 days after the second dose of vaccine was 95.0%" and "Efficacy against severe COVID-19 occurring after the first dose was 88.9%".

Journalists often seem to get these two mixed up.

I've read several threads on here now from people who have tested positive a month or so after getting the first jab so it could well be true. That being said 33% is better than nothing and people should still be taking the same precautions that they would have if they had not been vaccinated for now.

I think we’re very lucky that Israel has given us a heads-up. Be great if someone in power took note of intel from other countries for a change.

The other thing to bear in mind is that if efficacy is not getting a positive test for Covid-19, that isn't the same as gaining protection from serious disease. Surely at this stage, all we need is the latter. The more people that can be protected from serious disease the better, rather than a few people who will be so protected they never even get asymptomatic.
Herd immunity will never happen with only the elderly and vulnerable immunised.

@supercatpowers

The other thing to bear in mind is that if efficacy is not getting a positive test for Covid-19, that isn't the same as gaining protection from serious disease. Surely at this stage, all we need is the latter. The more people that can be protected from serious disease the better, rather than a few people who will be so protected they never even get asymptomatic. Herd immunity will never happen with only the elderly and vulnerable immunised.

Exactly and as I said further up the thread, Pfizer said up to 90% protection from severe disease after the first dose, not protection from Covid infection.

Pfizer FDA guidance notes said: "...efficacy in preventing confirmed COVID-19 occurring at least 7 days after the second dose of vaccine was 95.0%" and "Efficacy against severe COVID-19 occurring after the first dose was 88.9%".

Journalists often seem to get these two mixed u

My friend was vaccinated recently and told it would be 30% effective for two weeks then "up to" 70% effective (which could mean 1%) between then and the second jab.

It's a total cock up. They should be vaccinating people in accordance with the manifacturers instructions.

Read the above. The 30% figure simply isn't saying what they think it is.
It is nearly 90% protection against severe disease after one dose.

@User133847

We always knew two doses were needed anyway?
We were told the Pfizer jab was 90% effective with one dose and 95% effective after the two doses.

If only 33% with one dose and we are then going to wait 12 weeks rather than 3 for the second dose that the manufacturer recommends, how effective will it be after that 2nd dose?

Does anyone know how that compares with the Oxford vaccine? Is that any more effective after the first dose alone I wonder?

• I can't think this can be true. NHS frontline staff (proper frontline staff treating hundreds of Covid patients every shift) were given Pfizer. They PPE is crap in relation to the massive viral loads on general Covid wards (not ICU) - paper masks, plastic pinny. They are walking around in clouds of virus everyday. I think we'd know if 70% of them developed Covid after the first dose. Some of them did certainly, but not 70%.*

I don't think your logic is sound here. It would mean 100% of those staff would have contracted COVID prior to being given the jab?!

@Benjispruce2

Top scientists and medics agreed the 12 week delay as safe.

But Pfizer didn't, they even wrote to the Govt telling them they didn't approve.

@LegoAndLolDolls yeah, of course, I'm not under the impression that once vaccinated you can get back to doing whatever the heck you please! It's an expectation management thing for me, so that if even having had the first jab I still contract covid, I don't go into a slump of doom and gloom having had unrealistic beliefs about being magically safe having had the first dose.

You're not being an arsehole and it's definitely worth reminding people that vaccine or no vaccine, restrictions remain and must be adhered to.