[alancalverd]

swept any quantification of performance

Excess death statistics have always been available, and are credible in those countries that have effective mandatory registration of deaths.

It looks like NZ gave their corona policy up as a bad job

They had to resort to mass vaccination and crossed fingers after an airline crew broke quarantine and infected their first cohort. But as with any other vaccination program, it started too late for the first victims and thanks to antisocial media it's very difficult to establish herd immunity quickly. As with smallpox, we won't know if we have won for at least 20 years.

[Petrochemicals (OP)]

Screenshot_20230614_234924.jpg (253.25 kB . 1920x1200 - viewed 1139 times)

swept any quantification of performance

Excess death statistics have always been available, and are credible in those countries that have effective mandatory registration of deaths.

It looks like NZ gave their corona policy up as a bad job

They had to resort to mass vaccination and crossed fingers after an airline crew broke quarantine and infected their first cohort. But as with any other vaccination program, it started too late for the first victims and thanks to antisocial media it's very difficult to establish herd immunity quickly. As with smallpox, we won't know if we have won for at least 20 years.

Nonsense. New Zealand completes vaccination before it opened borders, whatever immunity was garnered from the programme was already present. Vaccination imbued herd immunity did not occour! The government gave up! The vaccines to not give immunity from corona infection, herd or otherwise.

[paul cotter]

Petro, for the record ( a ) I would take any vaccine that the science at that time deemed necessary ( b ) I live in Ireland so talk of hs2 is immaterial to me ( c ) I do not espouse homeopathy, it is abject nonsense. I think i'll drop out of the discussion now, as it is going nowhere.

[Petrochemicals (OP)]

Petro, for the record ( a ) I would take any vaccine that the science at that time deemed necessary ( b ) I live in Ireland so talk of hs2 is immaterial to me ( c ) I do not espouse homeopathy, it is abject nonsense. I think i'll drop out of the discussion now, as it is going nowhere.

Homeopathy is about as effective at creating herd immunity as the corona jab is the point? As for conspiracy

https://en.m.wikipedia.org/wiki/Irish_political_scandals

[alancalverd]

Homeopathy does not claim to produce herd immunity, and neither does vaccination by itself, as I explained earlier.

Even if you accept the precepts of homeopathy, it (in its classic form) depends on a very personalised diagnosis of existing disdease and is therefore as unsuitable for mass preventive care as knee surgery.

Herd immunity is a statistical result of immunising a closed group to the point that R << 1. That point has just about been reached in respect of poliomyelitis and definitely in the case of smallpox, but thanks to antisocial media, the growth of superstition, and the profitable baying of ignorant anti-humans we will probably never achieve it again.

[Petrochemicals (OP)]

herd immunity, and neither does vaccination by itself, as I explained earlier.

Yes, yes it does. We where promised a vaccine that would give herd immunity if we waited in lock downs for years. It failed to materialise. If not what were children given corona vaccinations for? They seem to be more than capable of developing immunity the normal way.

Herd immunity is a statistical result of immunising a closed group to the point that R << 1

Yes, which was promised but didn't happen.

[alancalverd]

Note the word "if". Every outbreak is traceable (in principle) to an infective person making contact with others - COVID isn't magic, and neither is quarantine. Deliberately placing infective persons in contact with vulnerable others as was ordered by the UK Health Secretary, is prosecutable as a war crime.

The maths is pretty obvious, despite the variable quality of the data. Excess deaths and the rate of infection were high in states with dense urban populations and groups with low vaccination uptake.There is some more advanced mathematics concerned with delayed and amplified propagation, but it requires a receptive audience, not a prejudiced one.  But a lesson worth learning is that you should never trust a politician, especially when he says "trust me".

[Kryptid]

There is nothing to suggest that in anything I have typed

Actually...

As for vaccines, they have the effect of creating a weaker populace by ratio. The more you save the more vunerable your population becomes, the pandemic of corona situation will recurr more often as people gain ever more medical intervention.

You imply here that using medicine to save the weak is bad, particularly in light of what you said just before that:

There was an excellent way to bestow herd immunity on the super spreader community, that was called let them catch the virus.

[Bored chemist]

Deliberately placing infective persons in contact with vulnerable others as was ordered by the UK Health Secretary, is prosecutable as a war crime.

Only if there's a war.
Otherwise it's just simple multiple murder.

[Petrochemicals (OP)]

There is nothing to suggest that in anything I have typed

Actually...

As for vaccines, they have the effect of creating a weaker populace by ratio. The more you save the more vunerable your population becomes, the pandemic of corona situation will recurr more often as people gain ever more medical intervention.

Nope, just your interpretation, but rather than thinking about the statement and what would happen to the populace without medical intervention, or even asking me, you have told me what I said, either in error or deceit.

[Petrochemicals (OP)]

Note the word "if". Every outbreak is traceable (in principle) to an infective person making contact with others - COVID isn't magic, and neither is quarantine. Deliberately placing infective persons in contact with vulnerable others as was ordered by the UK Health Secretary, is prosecutable as a war crime.

The maths is pretty obvious, despite the variable quality of the data. Excess deaths and the rate of infection were high in states with dense urban populations and groups with low vaccination uptake.There is some more advanced mathematics concerned with delayed and amplified propagation, but it requires a receptive audience, not a prejudiced one.  But a lesson worth learning is that you should never trust a politician, especially when he says "trust me".

But the vaccines did not create herd immunity. See graphic illustration in earlier post about new Zealand.

[Kryptid]

Nope, just your interpretation, but rather than thinking about the statement and what would happen to the populace without medical intervention, or even asking me, you have told me what I said, either in error or deceit.

When the statement about vaccines and medical treatment immediately followed a statement calling letting people catch the virus an "excellent" way of reaching herd immunity, how are we supposed to interpret that?

[Petrochemicals (OP)]

Nope, just your interpretation, but rather than thinking about the statement and what would happen to the populace without medical intervention, or even asking me, you have told me what I said, either in error or deceit.

When the statement about vaccines and medical treatment immediately followed a statement calling letting people catch the virus an "excellent" way of reaching herd immunity, how are we supposed to interpret that?

Precisely the point.

[Bored chemist]

But the vaccines did not create herd immunity.

Nothing ever does.
It's a hypothetical ideal where absolutely everyone is totally immune.
And you can't do it- not least because the virus changes and people do too.

A vaccine can't do it (because you can't administer it to everyone- some will be allergic or whatever)
And you can't even do it by allowing the virus to run riot- because it will always miss some people- even if it's just newborn babies.
But what the vaccine did was save lives.
It did that two ways- firstly (and obviously) it reduced the harm in people who were exposed (They were less likely to get covid, less likely to have severe symptoms, less likely to get  long covid and less likely to die.)

So the vaccine is an unequivocally good thing.

The second way the vaccine saved lives was to slow the transmission of the virus through the population, thereby making it easier for healthcare systems to deal with those severely affected.

The point is that, by reducing the spread of the virus, vaccination got us much closer to herd immunity than we would have got without it.
And it did so without mass human sacrifice which is what the traditional type of "herd immunity" means.

PC seems to favour the version with the bigger death toll.

He doesn't seem to want to say why.

[alancalverd]

One more time: vaccination reduces R. Herd immunity occurs when R is reduced below whatever level is considered acceptable. In the case of the common cold, R is quite large but acceptable because the disease is rarely more than an inconvenience. In the case of COVID, any value greater than 1 is unacceptable because the symptoms are disabling, persistent, and frequently fatal.

Wikipedia puts it succinctly: 

For simple models, the proportion of the population that needs to be effectively immunized (meaning not susceptible to infection) to prevent sustained spread of the infection has to be larger than 1 - 1/R This is the so-called Herd immunity threshold or herd immunity level. Here, herd immunity means that the disease cannot spread in the population because each infected person, on average, can only transmit the infection to less than one other contact.

But there is no "simple model" in practice because

(a) R is a function not only of the disease itself but also of the social habits of the population, which is why you need quarantine (theoretically 100% effective at eliminating transmissible disease)  plus vaccination to account for the fact that 100% quarantine is not possible outside of a prison or specially-designed hospital and

(b) no vaccine is 100% effective against an evolving virus - we can only vaccinate for last week's most popular or most virulent version, and as COVID symptoms have several days' latency whilst the carrier is infectious, we don't really know which variant is the most virulent until it is too late.

[set fair]

... compared to the UK or usa Alan. Brazil also has

Didn't he play for Spurs?

[set fair]

The expectation that we could achieve herd  immunity through vaccination was collective madness. Corona viruses cause respiratory / digestive tract infections, with a lifecycle which involves reinfecting the same individual repeatedly, evolving to become resistant to the antibodies of previous variants. To achieve herd immunity there would have had to be a reason to believe that the vaccines could induce the immune system to do something that it can't do by infection induced immunity.

[Bored chemist]

The expectation that we could achieve herd  immunity through vaccination was collective madness.

Worked for smallpox.

Again, you seem to think that herd immunity is some"perfect" state where everyone is completely immune.
In fact it only requires that any infection will die out (eventually).

[alancalverd]

The expectation that we could achieve herd  immunity through vaccination was collective madness.

Who expected it? Maybe the Trumpian herd (except they didn't believe in vaccines) or the Disciples of Boris, but nobody with an ounce of common sense would believe that herd immunity could be achieved in the face of gross public ignorance and the Human Rights brigade.

o achieve herd immunity there would have had to be a reason to believe that the vaccines could induce the immune system to do something that it can't do by infection induced immunity.

Quite so. And that "something" is to generate effective antibodies before the target virus arrives.That's the historic difference between variolation (using a dilute sample of the infective agent variola) and vaccination (using cowpox agent vaccinia to protect against variola).

[paul cotter]

Variola is a dna virus and dna viruses are a lot more stable than rna viruses. Polio on the other hand is an rna virus yet it was practically eliminated before some cock-ups spoiled things. However polio was an ancient virus and probably had stabilised it's genetic make up( guess ). Covid on the other hand was a brand new human pathogen and was still actively producing variants.