Lesson to learn from Israel. Pfizer vaccine less effective than announced

[Cormoran]

www.theguardian.com/world/2021/jan/19/single-covid-vaccine-dose-in-israel-less-effective-than-we-hoped

It is known that a single dose doesn't guarantee whole protection, but Israel's numbers are showing that delaying the second dose might be a losing strategy.

So if any of you has received the first dose but not yet the second, keep acting as if you had received none and stay safe.

@Jetatyeovilaerodrome

Wait for me

People really need to look up the definition of indefinitely before going off on one. Read both parts.

From Cambridge Dictionary :-

for an unlimitedd* or unknownn amountt of timee*:

Hmm not sure why there were double letters in my copy and paste

Thank you @MoirasRoses for bringing some perspective to this conversation! The timescales just aren't long enough yet in any country to say either way so we're just going to have to be patient.

I think it's too early to say, because Israel is only at around the two week stage for the people it is monitoring. This explains it pretty well, so I agree that you can't compare the 2 week lowering of occurrence with the 3 week given we know immunity rises a lot between day 15 and 21.

news.sky.com/story/covid-19-real-world-analysis-of-vaccine-in-israel-raises-questions-about-uk-strategy-12192751

Having said that, what is really impressive about the Israeli programme is that they are tracking 200,000 who have had the vaccine vs 200, 000 who haven't (yet) which is not small numbers, it's bigger than the trials, plus it's in the real world population.

Also they have vaccinated over 75% of their over 60s! This is an amazing test-bed for the Pfizer vaccine.

I don't think there's any reason to be negative about this, but if the data looks good from Israel, there would be a reason to follow their protocols.

@jetatyeovilaerodrome @spiratedaway wait for me!

People need to learn to read the complete information.

@notevenat20

The Guardian is not a good place for science news. Immunity from the first dose increases over three weeks. It would be very interesting if they had told us how many had got ill after 15 days, say, and how ill they had got but we will need a more scientifically literate source for that.

Sky news is reporting a 33% decrease in positivity at 14 days post vaccination from the Israeli data.

news.sky.com/story/covid-19-real-world-analysis-of-vaccine-in-israel-raises-questions-about-uk-strategy-12192751

"Sky news is reporting a 33% decrease in positivity at 14 days post vaccination from the Israeli data."

But what are you interpreting that to mean?

I'd prefer to follow the manufacturer guidelines. They carried out all the clinical studies, not the UK govt.

This is the crucial part of the Sky article:-

But on day 14 post-vaccination, a drop of 33% in positivity was witnessed in the vaccinated group and not in the unvaccinated... this is really good news."

From the Guardian article, about people who developed Covid after vaccination:

in most cases this was because the individuals had not built up sufficient antibodies after being inoculated before being exposed to the virus.

You have zero protection for the first 12 days, then it suddenly kicks in. Pfizer’s research reports 52% protection from one dose, but virtually all of the cases in the vaccine group occurred in the first 12 days after innoculation. Hardly any between 12 and 21 days.

So if instead of asking “what percentage protection do you have from one dose?” and count all the cases, you ask “how much protection do you have from 12 days after one dose,” the answer is 90%. That is the basis on which JCVI/MHRA have authorised the strategy we are currently pursuing. Protection rises to 95% after the second dose.

What we don’t know, because it wasn’t tested, is how long the 90% immunity after 12 days is maintained when the 2nd dose is delayed to 10-12 weeks.

We will find out in due course.

Covid positivity? Or did they just get pessimism as a side effect?

@CKBJ You may be interested to read this :

www.sciencemag.org/news/2021/01/could-too-much-time-between-doses-drive-coronavirus-outwit-vaccines

As the virologist states, the UK are a current live experiment in lengthening vaccine dose intervals.

Nicola Sturgeon was very clear today that because of this, restrictions will be in place for the foreseeable future, primarily to prevent Long COVID.

Really? How awful!

@Lifeinaonesie

Covid positivity? Or did they just get pessimism as a side effect?

They were spending time on Mumsnet

I hope someone in the UK is keeping data about frontline NHS staff treating Covid-19 patients. These staff pretty much all got the Pfizer vaccine (if they were given at the start when they were supposed to, some trusts mucked it up and some staff were late getting vaccinated).

These staff who got the Pfizer drug and treat Covid-19 patients in large wards with inadequate PPE (not so much ICU, but the many other Covid wards) would be doing weekly lateral flow tests. it would be interesting to see how many tested positive after their first dose of Pfizer since they can't continue to stay at home when their workplace makes them work in a cloud of SARS-CoV-2 with inadequate PPE.

@jasjas1973

We know one dose isn't enough. No one has ever said it is

Haven't they?
The govt has said 90% immunity after one dose, what on earth is that telling us all?

The govt scientists tweaked how efficacy was calculated by altering the start day (for immunity) from day 1 to day 10 this upped it from 50% to 90%.

Totally against what Pfizer did in their trials.

Well you are never going to have immunity on day 1. It takes time to build up.

The calculated that one dose was 90% effective by looking and infections between 10 days and 21 days (ie before next dose).

The vaccines aren’t perfect. And a twelve week gap isn’t perfect. BUT it’s best for the population.

It was always implied that the vaccine would be an additional layer of protection and not the sole remedy.
It only appears that the additional protection is not as good without the second layer and since many countries are looking at delaying the second dose to vaccinate a majority of people, it might be time to rethink this strategy .

It appears those vaccinated are less likely to get tested skewing the data

There is nothing magic about 3 weeks. Its not as if the trials tried 2,3,4,5 etc weeks and decided 3 was best.

They chose 3 because that was the shortest time they could be pretty sure of getting measureable impact. Normal trials would have a longer interval before the booster because immune response takes time to build up. (shortest time chosen obviously to get the vaccine into acceptance asap)

It would be normal for a stronger response at eg 4/5/6 weeks than 3.

The only caveat is that the pfizer vaccine is novel and could conceivably behave different to traditional vaccines - but that would mean the immune system behaving differently.

The oxford vaccine is more traditional and would be expected to behave like other vaccines in the same class and continue to increase in effectivity well beyond 3 weeks.

The level of effectivity shown at 3 weeks is already better than many vaccines (eg bcg)

Excellent post @FrankieStein402

The govt scientists tweaked how efficacy was calculated by altering the start day (for immunity) from day 1 to day 10 this upped it from 50% to 90%
Totally against what Pfizer did in their trials

I wasn't aware of the UK scientists' "tweaking" the efficacy and wondered if you have a source please?

After all we're constantly told on here how impartial they are and how utterly impervious to government pressure, so if this is true I'd like to know what the motivation might have been?

[quote Cormoran]@WiseUpJanetWeiss it may have only started on the 19th December but 22% of the population has already received the first dose against 4.5% for the 2 doses and highest number of infection in last 3 months despite a lockdown.[/quote]
We know from the data that the first Pfizer dose gives good, but not complete protection after about 14 days. The people receiving the vaccine on 19th would have started to have some protection by about 2 Jan. Those vaccinated at the end of that week would not have been protected until 9 Jan or thereabouts. So given that it takes a few days after infection to show symptoms and test positive, we’re looking at only about a quarter of those vaccinated so far having any reasonable expectation of having any protection. So it’s unsurprising that vaccinated people are testing positive now, because they were most likely infected before their immunity had any chance to kick in.

So far this is a non-story and a piece of scientifically illiterate journalism from the Guardian (imagine!).

It may yet turn out to be a big story, but until we have data it’s just gossip.

So if instead of asking “what percentage protection do you have from one dose?” and count all the cases, you ask “how much protection do you have from 12 days after one dose,” the answer is 90%.

This is incorrect.