I fucking knew it. Second vaccine dose.

[NiceGerbil]

News is that people who have had first dose are only getting second 3 months later. Against the guidelines of the org who made the vaccine.

I said this rush to push it out would result in, how are they going to follow up and make sure they get the second?

And here we go. Second dose not organised. UK govt say this is AOK.

FFS. I'd rather they took the time to do it properly. But hey. Pissup in a brewery situation again.

I said a few days ago to DH. Are they properly tracking this to make sure the follow up jab isn't missed?

I was too optimistic. Govt have decided second jab isn't that important.

FFS.

@cbt944

These people are very stupid. If they arrive at the decision you outline at least they have 70-90% chsnce of being protected.

I think it's more like 52% after the initial dose.

As has been posted previously, the 52% is misleading. It refers to the average protection over the three weeks after the first dose. Actually immunity kicks in after around 11 days, so it goes from 0 to around 90%.

As you can see on the chart the placebo and vaccine groups have the same number of infections until 11 days and then the vaccine group flattens while the placebo group continues to rise.

As has been posted previously, the 52% is misleading. It refers to the average protection over the three weeks after the first dose. Actually immunity kicks in after around 11 days, so it goes from 0 to around 90%.

This is simply not true. You are looking at a line that carries on after dose 2.

Have a look at
a/ the highest figure in the dataset for after dose 1 and before dose 2 and
b/the lowest figure in the dataset for the vaccine efficacy for day 21-28.

It isn't 90%.

It is only 90% as an average after dose 2.

There is though a group of 50 people that had only one dose? First line? With 82% efficacy? Or am I reading that wrong?
What I cannot see is up to how many days they checked it.
I have been reading a bit more about it, and I think Moderna (which is the same type of vaccine) tested up to 108 days with one dose.
They still have gone for two doses, I think.
If the 82-89% is reliable after one dose, up to 12 weeks, we should be ok.
I am hoping this actually works!

@MushMonster

There is though a group of 50 people that had only one dose? First line? With 82% efficacy? Or am I reading that wrong? What I cannot see is up to how many days they checked it. I have been reading a bit more about it, and I think Moderna (which is the same type of vaccine) tested up to 108 days with one dose. They still have gone for two doses, I think. If the 82-89% is reliable after one dose, up to 12 weeks, we should be ok. I am hoping this actually works!

No, from column left to right:

Time period
Number of people in the vaccine group who got covid
Number of people in the placebo group who got covid
Percent efficacy.

So, after dose 1 (and until the end of data collection) 50 people in the vaccine group got covid, and 275 in the placebo group got it. The efficacy for that whole period - so from the day the first dose was given to the end of the trial - was 82%. This includes the period of ten days or so at the start of the trial, after the first dose had been given, but before it kicked in.

The subsequent lines then break that down. So, of those 50 cases, 39 were after dose 1 and before dose 2. 2 were in the 7 days after dose 2 (therefore before dose 2 kicked in). 9 were at least 7 days after dose two (until the end of the trial.) The efficacies for those periods are 52.4%, 90.5%, and 94.8%.

The graph enables you to look in more detail at the 39 cases in the vaccine group which occurred between dose 1 and dose 2. These overwhelmingly occurred in the first half of that three week period, before any immunity kicked in. If you look at the period from day 15 after the first dose to 21 days, the efficacy is 89%. This is not listed in the table, but can be calculated from the data in the article.

The JCVI states:

Published efficacy between dose 1 and 2 of the Pfizer vaccine was 52.4% (95% CI 29.5-68.4%). Based on the timing of cases accrued in the phase 3 study, most the vaccine failures in the period between doses occurred shortly after vaccination, the period before any immune response is expected. Using data for those cases observed between day 15 and 21, efficacy against symptomatic COVID-19 was estimated at 89% (95% CI 52-97%), suggesting that short term protection from dose 1 is very high from day 14 after vaccination. Similar findings were seen with the Moderna mRNA vaccine out to 108 days after the first dose (see Annex A).

Source: app.box.com/s/uwwn2dv4o2d0ena726gf4403f3p2acnu

This is what allows us to say with confidence that the efficacy at 21 days is around 90%, even if the second dose is not given. What is unknown is how long that efficacy lasts without a second dose. (In fairness, it is also unknown how long efficacy lasts with a second dose - there simply hasn't been enough time elapsed for that.)

@MushMonster

There is though a group of 50 people that had only one dose? First line? With 82% efficacy? Or am I reading that wrong? What I cannot see is up to how many days they checked it. I have been reading a bit more about it, and I think Moderna (which is the same type of vaccine) tested up to 108 days with one dose. They still have gone for two doses, I think. If the 82-89% is reliable after one dose, up to 12 weeks, we should be ok. I am hoping this actually works!

You are reading it wrong. The 50 is the total number of participants who received the vaccine who tested positive after receiving the vaccine. The numbers below are a breakdown of when they tested positive. The right hand set of data are for the placebo arm.

The efficacy data (far right) shows an average of 52% efficacy between dose 1 and dose 2. This includes people testing positive at any time between the first and second dose. The graph shows the actual interval, and as you would expect, the rate of positives mirrors the placebo arm for the first week or so (effect has not yet kicked in) but then flattens dramatically between days 10 and 14, and follows the same trajectory past the second dose.

The JCVI conclude that this flattening will continue regardless of the second dose. What they don’t know is when the curve then bends upwards again. Data from the AZ vaccine, and I believe from the Moderna vaccine (press reports), suggests that immunity doesn’t wane quickly, so deferring the second dose to 12 weeks is most likely not to be a problem, and will have significant benefits in terms of roll out to protect more people.

I agree with everything @WiseUpJanetWeiss said. She managed it in half the words I did, and clearer.

This is the key point: "What they don’t know is when the curve then bends upwards again."

We don't know what happens on day 22 if you don't give the second dose. Immunity might jump up to 100%. It might drop to zero. The virus might rampage your DNA so you grow a lizard-tail. Okay, probably not that last.

The likelyhood is it will neither jump to 100% or plummet overnight to nothing. It will taper off gradually. How gradually? Noone knows. But the JCVI considers, based on their knowledge of the immune system, how other vaccines have worked, and the data from Moderna (fundamentally a very similar vaccine) that it is unlikely to drop off within 12 weeks to the point where the risk to the population is greater than leaving another cohort with no vaccine at all.

Is it an unknown? Yes. Is it a gamble? Yes. Would we do this in normal times? Hell no.

But these aren't normal times, and it's a pretty safe strategy under dire circumstances, because the risks of the alternate option are much worse.

@WiseUpJanetWeiss thanks , maybe I am worrying too much about the future instead of the here and now !

Thanks for explaining. I am seeing the graph and table in the phone, so it is not that clear

Some more figures:

A million people have had the first vaccine. If they have the second jab in the next week or two, that's a million people who won't get the first vaccine yet. All - because those are the only ones who are getting it right now - the most vulnerable.

Say 1% of those get covid. That's 10,000 cases.

Fatalities in the 80+ age group are between 10-20%, depending on which research you look at. So that's conservatively 1000 deaths which could be saved by diverting those million doses.

As more doses are rolled out, that effect increases.

Yes, it's shit for those who have had their first dose and who - totally understandably - are scared and confused by the change. But it's the lest bad decision.

Many thanks @WiseUpJanetWeiss and @Motorina for putting into words while I was still trying to make sense!

When dissecting all the various efficacy data it is worth bearing in mind that less than 300 people out of over 20,000 in the placebo arm were diagnosed as symptomatic. This is not a lot of data to go on and indicates a prevalence at time of study somewhat below current UK levels.

Evidence of efficacy of any sort for any length of time is scant. Therefore all options are a "gamble".

@Motorina

I agree with everything *@WiseUpJanetWeiss* said. She managed it in half the words I did, and clearer.

This is the key point: "What they don’t know is when the curve then bends upwards again."

We don't know what happens on day 22 if you don't give the second dose. Immunity might jump up to 100%. It might drop to zero. The virus might rampage your DNA so you grow a lizard-tail. Okay, probably not that last.

The likelyhood is it will neither jump to 100% or plummet overnight to nothing. It will taper off gradually. How gradually? Noone knows. But the JCVI considers, based on their knowledge of the immune system, how other vaccines have worked, and the data from Moderna (fundamentally a very similar vaccine) that it is unlikely to drop off within 12 weeks to the point where the risk to the population is greater than leaving another cohort with no vaccine at all.

Is it an unknown? Yes. Is it a gamble? Yes. Would we do this in normal times? Hell no.

But these aren't normal times, and it's a pretty safe strategy under dire circumstances, because the risks of the alternate option are much worse.

This, with bells on. 🙂

Apart from the clarity bit - I thought yours was better.

@WiseUpJanetWeiss it was certainly more verbose

[quote Motorina]@WiseUpJanetWeiss it was certainly more verbose [/quote]
Some of us like detail. 🙂

I do hope the strategy pays off indeed.
It would be a great advantage if one dose will cover for the 12 weeks.
I am still worried about children not having a licensed vaccine. Though I suppose once we have more data about these ones, and the transmission, their vaccine will be shortly ready should it be needed.

@mushmonster, indeed!

It's actually ethically really fascinating, because what is in effect happening is a giant clinical trial without ethics approval or consent of the participants. The justification is ensuring the greatest good of the greatest number - pure utilitarianism - but it undoubtedly breaches the autonomy of those who have in effect been enrolled in a clinical trial without their consent.

If you'd said to me a year ago that that would be happening in the UK, then I would have laughed in your face. But would anyone have believed this year, a year ago?

It will keep PhD writers happily entertained for years.

It's actually ethically really fascinating, because what is in effect happening is a giant clinical trial without ethics approval or consent of the participants. The justification is ensuring the greatest good of the greatest number - pure utilitarianism - but it undoubtedly breaches the autonomy of those who have in effect been enrolled in a clinical trial without their consent.

Absolutely this.

Utilitarianism is a very slippery slope.

Well, yes. It's also an important principle. The NHS (and for that matter education) are largely propped up by people sacrificing their time, energy and - right now - health, for the public good. I dread to think how much unpaid overtime people in both those services provide.

I'm a clinician. Like many senior clinicians I have significant savings, and could well afford to take a year off til this mess is all over. It would absolutely be in my best interest. But I don't, like many of my colleagues. There's a thread on here from one clinician saying, "who do I first - my patients or my family?". Because of the greater good...

Do people really still think this vaccine works
Dear God.

@GypsyLee

Do people really still think this vaccine works Dear God.

The vaccine is proven in clinical studies to work, at least in the short term, not sure why people wouldn't believe it? The implication is the part that people don't believe will work.

Imthe largest clinical trial in history indeed! There will be publications for long term.
Also, only illness I know of, in my time, where the idea is to vaccinate adults and no children. At least, that seems to be the idea at present.
I know it is based on the data showing that it does not affect young people and children, even the new variant does not seem to translate in higher illness rates. Which is great! I am just very wary of changes on this in the future.

Mush the flu vaccine was rolled out backwards from old to young. Routine flu vaccination of children in the UK is very recent. My DD3 is 9 and was iirc 6 before it was introduced in her school.

Another example would be shingles vaccine for elderly but not chickenpox for children.

Motorina it isn't really that cut and dried. Medicine is only a well paid secure profession as long as there are sick people to treat. "Survival of the fittest" would have far less use for medics. Euthanasia would be one route out of the nursing home dilemma.

I would not argue for either. I am NOT a utilitarian.

Yes, I know someone who got the first dose, was told it was very important to get the second when it was meant to be. Then had the appointment cancelled and told 'but the one dose on its own is 90% effective, the second only knocks it up a bit to 94%' or something, and that it didn't actually matter when the second dose was given but she will get it asap