A new population study from Israel, published in the Lancet on Wednesday, finds that the Pfizer vaccine is 95.3% effective against SARS-CoV-2 infection once a person is fully vaccinated (defined as being a week past their second dose). It also finds the vaccine is 94.8% effective in those aged 65 or older once fully vaccinated.
This is in line with other studies and is a very encouraging result. However, as with previous studies, it’s not clear how well the researchers have taken into account the fact that infections were declining anyway during the study period and whether this has led to an over-estimation of vaccine effectiveness.
To test this I accessed the data available from the Israeli Government. I looked at how many cases occurred in each age group each week alongside the proportion of that age group that had been fully vaccinated by that week. This allowed me to calculate how many infections we would expect to occur among vaccinated people in each age group each week if you assume the vaccines don’t have any effect. I then added these together to give a baseline number of cases in each age group to compare against the number of actual cases among the vaccinated as reported in the study. The results are shown below.
I calculated we would expect 43,826 infections among the vaccinated out of a total of 237,700 in the study period (January 24th to April 3rd) if the vaccines have no effect, which is 18.4%.
The study reports 6,266 infections among the vaccinated out of a total of 232,268 during the study period, or 2.7%. (I wasn’t able to discover why the study had about 2.3% fewer infections than the Israeli Government data broken down by age, but by using proportions we can avoid this discrepancy affecting the calculation.)
A proportion of 2.7% is 85.4% lower than a proportion of 18.4% that we estimated if the vaccines had no effect. This suggests a vaccine effectiveness of more like 85% than 95%.
Looking now at the crucial older age group, if the vaccines had no effect I have calculated we would expect 11,332 infections among the vaccinated aged 60 and over out of a total of 29,489 infections in that age group during the study period. The study found 2,201 infections among the fully vaccinated aged 65 or more. (It doesn’t state how many infections there were in total in this age group so we can’t calculate a straightforward proportion from the study.)
We need to adjust our expected figure of 11,332 to allow for the fact that it includes those aged 60-64 (the study uses different age brackets from the publicly available Government data). From the table above this will be about half of the infections in the 60-69 age group, or 2,834. We also need to reduce the expected figure by around 2.3% to allow for the different infection totals of the study and Government data. This gives us an expected figure of 8,329 infections among the vaccinated over 65s.
The 2,201 figure from the study is 73.6% smaller than 8,329, suggesting a vaccine effectiveness among the over 65s of more like 74% than 95%.
It’s not clear why the authors of the study did not do an analysis similar to this one. Taking into account the background prevalence of the virus should be basic, to avoid over-estimating the effectiveness of vaccines when they are rolled out during the decline of the epidemic.
The study (which was funded and approved for publication by Pfizer) briefly mentions lower vaccine effectiveness 2-3 weeks after the first dose, but does not give any information about effectiveness or infection incidence in the first 14 days. This means it gives no more information about the post-vaccination infection spike observed in other studies, though the silence here may be telling.
A further question is why the researchers gave no finer-grained detail about those older than 65 when they must have had the data to do so, and more than half of Covid deaths are in those aged over 80.
An effectiveness of 85% overall and 74% among the over 65s is still good, but it is not as good as the 95% figures in the study. As so often with vaccine studies, on closer inspection you’re left wondering whether you’re getting the full and accurate picture.
(This article has been corrected for some earlier mistakes in the numbers. The overall argument is unaffected.)
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More fool them
No – more propagandised and fearful them
Sadly notice a fair few older people wearing masks whenever they go out, and I’m sure they’ve been jabbed. The SPI-B psychopaths and their political masters opened Pandora’s Box and they wouldn’t be able to close it even if they wanted to.
agreed – keep having to remind my anxious parent that they are now twice vaccinated [much through I wish they were not – would far rather they were taking vitamin D] and have very little to worry about every time I am asked a series of questions about whether X or Y is safe and hear that they are “worried” about something to do with the relaxation of the covid restrictions. If only I could manage to stop them watching the news on the bogus broadcasting corporation…
Yep concur with that. Staying in a village in Wensleydale this w/e and it’s mask central. Bloke in the village shop asked why I wasn’t wearing one, very nearly replied that I wasn’t that gullible. A lot but especially the old continue wearing them in the street – very depressing.
Too much TV & Media.
I think there lies the problem.
Switch-off the TV and radio.
If there was no TV or radio would anyone really know that there had even been a pandemic?
Back in the 14th century during the Black Death which caused an estimated 50 million deaths there was no TV or radio back then (obviously) but you were aware that there was a deadly killer disease spreading through the population because people were dropping like flies absolutely everywhere (read the diaries back then) – yet I’ve still to meet or know anyone who knows of someone somehwere who has actually died of covid19 (not died with covid19) but actually died due to the covid virus.
Also Spartacus, even in 68(HK Flu) and 56/57( Asian flu) apart from the governments, 1 Labour and 1 Conservative respectively not panicking and running around in ever decreasing circles instructing us to isolate in our homes (or else), there wasn’t 24 hour rolling news on TV and radio constantly churning out propaganda and inane comments like “It’s the wettest May since the last wettest May!”.
Weird isn’t it. I was in a second-hand furniture emporium recently; a man and his wife – about 55 – made an absolute meal of getting past me, even though I was facing away from them in a large room with a 6-foot passageway. I flipped (slightly) and said “Oh for heaven’s sake you don’t need to make such a fuss – there’s no bloody virus here and nobody’s died in this area [mid-Norfolk] for months!” The man squared up to me as if I’d asked him for a fist-fight; “Oh yeah,” he shouted, “so how many people do YOU know who’ve died?” This suggested to me that he in fact knew people who’d died. “None,” I said. “Well,” quoth the sage, “my mother was very ill with it.” Substantial pause while I tried to fathom the man’s train of thought. “So,” I replied, “You don’t know anyone who’s died, either?” He just walked off.
Very odd, very disconcerting. Bizarre illogical remarks prompted by fear/anger/ignorance? People are enjoying their confinement; it’s making them feel significant, protected, part of something. It’s a measure of their country’s loss of identity and self-confidence. Very sad.
This. They’ve been terrorised, captive with often little to keep them company apart from a TV or Radio. It’s their communication with the mad, mad world outside and it’s full, wall to wall, with extreme Covid fear porn.
Postcard from the South Sandwich Islands
Day 22
At the SAGE meeting yesterday one of the Penguins brought up a new paper published this week in the Oxford scientific journal Clinical Infectious Diseases
The penguin seemed to suggest that the scientists had discovered something in the vaccinated that was not predicted and they don’t understand
I pointed out that this was not an agenda item and we must concentrate on Martin Bashir and Harry’s indescribable pain
Anyway said penguin went swimming this morning and never came back
So sad. He leaves a wife, children and the islands first Jamie Oliver franchise
I got told in one letter, in March that I was suddenly ” clinically, extremely vulnerable” and that should shield for a month…and book my jabs! It’s funny that I wasn’t considered so the whole of last year but come jab rollout time…time to try and frighten even more people into accepting it. Didn’t work on me though. Chucked it in the bin and carried on as usual.
I’ve had numerous texts and letters from my GP, noting my ‘underlying health issues’ (I haven’t got any!!) pushing me to book an appointment online or via the GP.
I’ve had 3 letters from the NHS directing me to book an appointment.
Several telephone calls. One caller left a message on my mobile, stating I need to contact them to discuss my ‘treatment plan’ regarding the injections!!
Oh – and a further 2 letters from my GP and one from some place else – inviting me to join clinical trials in the fight against Covid!!!!! I would of course, have a full medical health screen and travel costs would be reimbursed, whoopy doo!
Bog off to the lot of ‘em!!
oh the joys of not having a mobile phone of any kind – I seem to be below the radar and hope that I can manage to keep it that way for as long as possible
I’m going to find my old faithful basic Nokia – about 15 years old or more – and if it still works, start using that if / when I go out and apps are needed. Can’t download anything to it
In Kidderminster yesterday along with most of the country it was pouring down with rain,blowing a gale and bitter cold and yet there were the collaborators and sheep fully “facenappied up” outside. WHAT IS THE MATTER WITH THESE PEOPLE?
Later on, myself, Mrs FP and our younger son went for a meal and had to put up with the usual:”Have you signed in,sanitized your hands, etc”followed by: ” Follow the one way system and if you want to visit the toilet, don’t forget to wear your face nappy, etc”, but then a ray of sunshine (common sense); 3 workmen came in, one without a fn,ignored the instructions that I mentioned before and went to the bar if they wanted anything.
Oh, it did do my 72 year old heart good.
Thank you lads, whoever you are.
Stockholm syndrome, negative adaptation etc.
In Germany, one state wanted to eliminate the Mask mandate when the incidence no falls below 35.
The sheep revolted. They want to keep their masks on now!
(Highly manipulated and framed sampling of course, but still.)
https://www.ndr.de/nachrichten/niedersachsen/Maske-im-Einzelhandel-bleibt-Niedersachsen-lenkt-ein,corona7926.html
Bonkers! and there I was thinking the Germans were a sensible logical nation.
Fine by me if they spend the rest of their lives hiding ‘safe’ at home. Leaves more room for the rest of us to enjoy being out and about.
HEAR,HEAR!!!
Well, yes, except if one of the fearful is a close friend or family member, it’s causing you direct pain.
Narrative is now that as we had to mask up to make the timid feel safe, we should talk part in the global experiment to achieve the same.
Anyone with an insight into anxiety-based mental illness knows that this is precisely the wrong way to get over it. It reinforces irrational fear.
Of course they’re still shielding the BBC et al are constantly sending out the message it’s really dangerous out there and we’re all (well mostly, not me) muzzled up everywhere.
They scared them now they need to de-programme them.
The irony is they are inside eating cakes and getting fatter – thus more suceptible to the rare killer sniffles aka covid agenda 21.
Much easier to scare people than to unscare them.
I wonder why only 2/3 have been fully vaccinated? I thought the shielders were right near the top of the list? I wonder if this means that a significant proportion of them can’t/won’t have it? Which I fully respect of course, it’s their lives and bodies but if even they don’t want it then as a perfectly fit and healthy person I do resent being told I need to get it to protect them or to be allowed to live my life fully!
Only 40% of vulnerable people typically take up the offer of a flu jab and obviously it’s not offered to the rest of us so I wish we could just go back to that.
I have two neighbours, who have lived this way for 14 months…they are not much over 40, wont allow anyone in, not even a tradesman, have free groceries delivered every week and unless they have a home gym tucked away somewhere, cant be getting ANY exercise. Neither are stupid but they apparently say they will not go outside or let anyone in until they have their jabs, later on in the year. It’s just beyond tragic.
A relative of ours (woman in her late 40s) is obsessed with keeping her home germ free, she sanitises all the time. Her son, in his 20s, sensibly, goes out and about seeing friends etc….his mum is in bed when he comes in at night but listens for his key in the door and gets up and disinfects everywhere in case he’s brought the dreaded virus in with him. Totally paranoid.
“Neither are stupid” you sure?
It is very sad that some people have been so taken in by the fear generated by Government at the behest of SAGE in March 2020 that they are still terrified to leave the house. My sister’s in-laws are amongst this group – they even have testing kits for family members to use when visiting (and then wait outside in the car for 30 minutes). They are so scared of dying that they are not living! And as for people wearing masks outdoors – just don’t get me started. I see young people, middle aged people, old people all wearing the things when walking along the street or in green public spaces – what is the matter with them?
Zombies