Today's Proceedings of the (US) National Academy of Sciences includes a paper with an interesting abstract.

https://www.pnas.org/content/118/33/e2100814118

I may be able to get hold of a copy of a .pdf of the whole paper if anybody is interested.

The experimental part exploits a screw-up in the UK contact tracing program that meant that some 20% of the people who should have been contacted weren't. Apparently them getting contacted reduced new infections by 63% and deaths by 66%, which is quite a lot.

--
Bill Sloman, Sydney

On Tuesday, August 17, 2021 at 11:21:13 PM UTC-4, bill....@ieee.org wrote:
> Today's Proceedings of the (US) National Academy of Sciences includes a paper with an interesting abstract.
>
> https://www.pnas.org/content/118/33/e2100814118
>
> I may be able to get hold of a copy of a .pdf of the whole paper if anybody is interested.
>
> The experimental part exploits a screw-up in the UK contact tracing program that meant that some 20% of the people who should have been contacted weren't. Apparently them getting contacted reduced new infections by 63% and deaths by 66%, which is quite a lot.

I think this is one of those things that is pretty durn obvious. Like doing research on what happens when you let go of an object, does it fall?

If nothing else, we will eventually learn something about dealing with pandemics. Unfortunately, we are not so likely to learn much about dealing with the causes of the failures to deal with pandemics such as denial on the part of citizens and politicians or an undue emphasis on the preservation of "freedom".

Like I've said a number of times, if the death rate were just somewhat higher, I think much of the resistance to dealing with the disease would not have appeared. It really takes a whack job to think that requiring masks and limiting gatherings in large groups is a significant or undue restriction on freedoms. These days we don't need gatherings at all with the communications possible over the Internet. The gatherings are just a way for people to be massaged and corralled. The real influencing is online anyway. The government doesn't control that... not in the West anyway.

--

Rick C.

- Get 1,000 miles of free Supercharging
- Tesla referral code - https://ts.la/richard11209

On Tue, 17 Aug 2021 20:21:10 -0700 (PDT), Anthony William Sloman
<bill.sloman@ieee.org> wrote:

>Today's Proceedings of the (US) National Academy of Sciences includes a paper with an interesting abstract.
>
>https://www.pnas.org/content/118/33/e2100814118
>
>I may be able to get hold of a copy of a .pdf of the whole paper if anybody is interested.
>
>The experimental part exploits a screw-up in the UK contact tracing program that meant that some 20% of the people who should have been contacted weren't. Apparently them getting contacted reduced new infections by 63% and deaths by 66%, which is quite a lot.

Would be interested in pdf, just not willing to
pay for it.

RL

On Thursday, August 19, 2021 at 12:54:44 PM UTC+10, legg wrote:
> On Tue, 17 Aug 2021 20:21:10 -0700 (PDT), Anthony William Sloman
> <bill....@ieee.org> wrote:
>
> >Today's Proceedings of the (US) National Academy of Sciences includes a paper with an interesting abstract.
> >
> >https://www.pnas.org/content/118/33/e2100814118
> >
> >I may be able to get hold of a copy of a .pdf of the whole paper if anybody is interested.
> >
> >The experimental part exploits a screw-up in the UK contact tracing program that meant that some 20% of the people who should have been contacted weren't. Apparently them getting contacted reduced new infections by 63% and deaths by 66%, which is quite a lot.
>
> Would be interested in pdf, just not willing to pay for it.

A contact inside the university system has sent me a copy. E-mail me at bill.sloman at ieee.org, and I'ii send a copy on to you, Strictly for private study, of course.

--
Bill Sloman, Sydney

On 18/08/2021 04:21, Anthony William Sloman wrote:
> Today's Proceedings of the (US) National Academy of Sciences includes
> a paper with an interesting abstract.
>
> https://www.pnas.org/content/118/33/e2100814118
>
> I may be able to get hold of a copy of a .pdf of the whole paper if
> anybody is interested.

I'd be interested in a look. The surprise to me is that the UK national
test and trace scheme was even remotely effective. Anecdotally they were
a complete shower ringing the same home 70 times in one day and missing
many others completely. Local authority tracing was much better but the
central lot wouldn't give them the data fast enough to make it work!

UK test and trace was led by someone who was the former CEO of the UK's
mobile company with the worst customer service ever - ideal choice!

Work was subcontracted to a firm who has a previous conviction for
defrauding the Ministry of Justice. You really couldn't make it up!

> The experimental part exploits a screw-up in the UK contact tracing
> program that meant that some 20% of the people who should have been
> contacted weren't. Apparently them getting contacted reduced new
> infections by 63% and deaths by 66%, which is quite a lot.

That "coding error" as they so quaintly call it was using a pre-historic
Excel spreadsheet pre 2007 .XLS format as a *database*. Silently hitting
the 65k line limit and discarding any records that wouldn't fit.

It is an interesting serendipitous piece of research.

Oxford study has some more on Pfizer vs AZ vaccines against Delta.
Pfizer wanes markedly from its initial high efficacy to about the same
as AZ on about a 5 month timescale. It remains unclear what happens
beyond that (although Isreals 40% reported might be a hint).

https://www.ndm.ox.ac.uk/covid-19/covid-19-infection-survey/results/new-studies

Delta makes vaccinated people just as infectious as unvaccinated ones.
Alpha and earlier variant transmission is almost stopped by vaccination.

--
Regards,
Martin Brown

On Thursday, August 19, 2021 at 6:21:14 PM UTC+10, Martin Brown wrote:
> On 18/08/2021 04:21, Anthony William Sloman wrote:
> > Today's Proceedings of the (US) National Academy of Sciences includes
> > a paper with an interesting abstract.
> >
> > https://www.pnas.org/content/118/33/e2100814118
> >
> > I may be able to get hold of a copy of a .pdf of the whole paper if
> > anybody is interested.

<snip>

> > The experimental part exploits a screw-up in the UK contact tracing
> > program that meant that some 20% of the people who should have been
> > contacted weren't. Apparently them getting contacted reduced new
> > infections by 63% and deaths by 66%, which is quite a lot.
>
> That "coding error" as they so quaintly call it was using a pre-historic
> Excel spreadsheet pre 2007 .XLS format as a *database*. Silently hitting
> the 65k line limit and discarding any records that wouldn't fit.
>
> It is an interesting serendipitous piece of research.
>
> Oxford study has some more on Pfizer vs AZ vaccines against Delta.
> Pfizer wanes markedly from its initial high efficacy to about the same
> as AZ on about a 5 month timescale. It remains unclear what happens
> beyond that (although Isreal's 40% reported might be a hint).

You have a habit of confusing antibody titres with efficacy.
> https://www.ndm.ox.ac.uk/covid-19/covid-19-infection-survey/results/new-studies
>
> Delta makes vaccinated people just as infectious as unvaccinated ones.

For a short while - they don't seem to stay infected or infectious for all that long, which means that from the pojnt of view of infecting other people they aren't as infectious as the unvaccinated. They may be just as infectious while they are infected, though what seems to be be measured is virus counts on nose and throat swabs, but the duration of the infectious period also matters. They aren't going to Typhoid Marys - she stayed infectious all her life, and was locked up for her last thirty years.

> Alpha and earlier variant transmission is almost stopped by vaccination.

--
Bill Sloman, Sydney

On 19/08/2021 15:54, Anthony William Sloman wrote:
> On Thursday, August 19, 2021 at 6:21:14 PM UTC+10, Martin Brown
> wrote:
>> On 18/08/2021 04:21, Anthony William Sloman wrote:

>> Oxford study has some more on Pfizer vs AZ vaccines against Delta.
>> Pfizer wanes markedly from its initial high efficacy to about the
>> same as AZ on about a 5 month timescale. It remains unclear what
>> happens beyond that (although Isreal's 40% reported might be a
>> hint).
>
> You have a habit of confusing antibody titres with efficacy.

I have a great liking of quantitative things that can be measured.

I know other parts of the immune system may provide some longer term
immunity but it is beginning to look like Pfizer doesn't where AZ does.
Better Israeli data on this question of fading immunity should be
available fairly soon - their preliminary results look worrying to me.

>> https://www.ndm.ox.ac.uk/covid-19/covid-19-infection-survey/results/new-studies
>>
>>
>> Delta makes vaccinated people just as infectious as unvaccinated ones.
>
> For a short while - they don't seem to stay infected or infectious
> for all that long, which means that from the pojnt of view of
> infecting other people they aren't as infectious as the unvaccinated.

UK transmission levels at the moment suggest that isn't true. The levels
of Covid infection are stable but relatively high at 30k/day. And about
equally split across vaccinated people (>75% adults) and unvaccinated.

https://www.bbc.co.uk/news/uk-51768274

It might go even higher when schools and universities reopen for
Michaelmas term. They are the last cohort to get the vaccine.

Patients in hospital with Covid remains static at 6k and deaths are
still continuing to rise slowly but remain around 100 daily.

> They may be just as infectious while they are infected, though what
> seems to be be measured is virus counts on nose and throat swabs, but
> the duration of the infectious period also matters. They aren't going

That doesn't seem to make much difference in practice since not getting
sick at all means they interact much more than their sickly unvaccinated
counterparts. Both have massive viral loads in the early stages of the
infection and before any symptoms appear.

> to Typhoid Marys - she stayed infectious all her life, and was locked
> up for her last thirty years.

That was a figure of speech not intended to be taken literally.

The big problem in the first wave which killed so many elderly care home
patients was itinerant care staff infected with Covid but with no
apparent symptoms spread the disease into a very vulnerable group.

It wasn't helped by inadequate sick pay and zero hours contracts meaning
that some of them could not afford to take time off to isolate even if
they thought they were ill (and that losing all sense of smell was not
an official Covid symptom in the UK for so long).
>
>> Alpha and earlier variant transmission is almost stopped by
>> vaccination.

We will have to wait and see how it pans out.

--
Regards,
Martin Brown

On Friday, August 20, 2021 at 5:59:55 PM UTC+10, Martin Brown wrote:
> On 19/08/2021 15:54, Anthony William Sloman wrote:
> > On Thursday, August 19, 2021 at 6:21:14 PM UTC+10, Martin Brown
> > wrote:
> >> On 18/08/2021 04:21, Anthony William Sloman wrote:
>
> >> Oxford study has some more on Pfizer vs AZ vaccines against Delta.
> >> Pfizer wanes markedly from its initial high efficacy to about the
> >> same as AZ on about a 5 month timescale. It remains unclear what
> >> happens beyond that (although Isreal's 40% reported might be a
> >> hint).
> >
> > You have a habit of confusing antibody titres with efficacy.
>
> I have a great liking of quantitative things that can be measured.

Less enthusiasm for working out whether what has been measured actually means what you'd like it to mean.
> I know other parts of the immune system may provide some longer term
> immunity but it is beginning to look like Pfizer doesn't where AZ does.

But what makes you think that?

> Better Israeli data on this question of fading immunity should be
> available fairly soon - their preliminary results look worrying to me.

Again, they seem to have been measuring antibody titres, rather than hospital admissions.

> >> https://www.ndm.ox.ac.uk/covid-19/covid-19-infection-survey/results/new-studies
> >>
> >> Delta makes vaccinated people just as infectious as unvaccinated ones.
> >
> > For a short while - they don't seem to stay infected or infectious
> > for all that long, which means that from the point of view of
> > infecting other people they aren't as infectious as the unvaccinated.
>
> UK transmission levels at the moment suggest that isn't true. The levels
> of Covid infection are stable but relatively high at 30k/day. And about
> equally split across vaccinated people (>75% adults) and unvaccinated.
>
> https://www.bbc.co.uk/news/uk-51768274

Which doesn't say anything about who is doing the infecting.

The actual number of fully vaccinated people is 41,157.069 out of a population of about 68 million - 60%.

It may be 75% of the adults, but delta does seem to be infecting kids, and they can infect other people.

> It might go even higher when schools and universities reopen for
> Michaelmas term. They are the last cohort to get the vaccine.
>
> Patients in hospital with Covid remains static at 6k and deaths are
> still continuing to rise slowly but remain around 100 daily.
>
> > They may be just as infectious while they are infected, though what seems to be be measured is virus counts on nose and throat swabs, but the duration of the infectious period also matters. They aren't going to become Typhoid Marys - she stayed infectious all her life, and was locked up for her last thirty years.
>
> That doesn't seem to make much difference in practice since not getting
> sick at all means they interact much more than their sickly unvaccinated
> counterparts. Both have massive viral loads in the early stages of the
> infection and before any symptoms appear.

They don't. If they had massive viral loads they'd have symptoms.

> That was a figure of speech not intended to be taken literally.

Unfortunately, it conveys the idea of somebody who is persistently infected.. which isn't going to happen. Your thinking on the subject does seem to be dangerously over-simplified, and it was a revealing error.
> The big problem in the first wave which killed so many elderly care home
> patients was itinerant care staff infected with Covid but with no
> apparent symptoms spread the disease into a very vulnerable group.
>
> It wasn't helped by inadequate sick pay and zero hours contracts meaning
> that some of them could not afford to take time off to isolate even if
> they thought they were ill (and that losing all sense of smell was not
> an official Covid symptom in the UK for so long).

The problem with Covid-19 always was that the infected did infect other people before they showed obvious symptoms. The 15% who never developed obvious symptoms were a problem, but since they never developed a high enough viral load to feel sick it isn't surprising that they infected fewer people than those who went on the symptomatic phase (who didn't infect all that many people after they were recognised as visibly sick).
> >
> >> Alpha and earlier variant transmission is almost stopped by vaccination.
>
> We will have to wait and see how it pans out.

But misunderstanding what you are seeing now isn't a good start.

--
Bill Sloman, Sydney

On 20/08/2021 09:36, Anthony William Sloman wrote:
> On Friday, August 20, 2021 at 5:59:55 PM UTC+10, Martin Brown wrote:
>> On 19/08/2021 15:54, Anthony William Sloman wrote:
>>> On Thursday, August 19, 2021 at 6:21:14 PM UTC+10, Martin Brown
>>> wrote:
>>>> On 18/08/2021 04:21, Anthony William Sloman wrote:
>>
>>>> Oxford study has some more on Pfizer vs AZ vaccines against Delta.
>>>> Pfizer wanes markedly from its initial high efficacy to about the
>>>> same as AZ on about a 5 month timescale. It remains unclear what
>>>> happens beyond that (although Isreal's 40% reported might be a
>>>> hint).
>>>
>>> You have a habit of confusing antibody titres with efficacy.
>>
>> I have a great liking of quantitative things that can be measured.
>
> Less enthusiasm for working out whether what has been measured actually means what you'd like it to mean.
>
>> I know other parts of the immune system may provide some longer term
>> immunity but it is beginning to look like Pfizer doesn't where AZ does.
>
> But what makes you think that?
>
>> Better Israeli data on this question of fading immunity should be
>> available fairly soon - their preliminary results look worrying to me.
>
> Again, they seem to have been measuring antibody titres, rather than hospital admissions.
>
>>>> https://www.ndm.ox.ac.uk/covid-19/covid-19-infection-survey/results/new-studies
>>>>
>>>> Delta makes vaccinated people just as infectious as unvaccinated ones.
>>>
>>> For a short while - they don't seem to stay infected or infectious
>>> for all that long, which means that from the point of view of
>>> infecting other people they aren't as infectious as the unvaccinated.
>>
>> UK transmission levels at the moment suggest that isn't true. The levels
>> of Covid infection are stable but relatively high at 30k/day. And about
>> equally split across vaccinated people (>75% adults) and unvaccinated.
>>
>> https://www.bbc.co.uk/news/uk-51768274
>
> Which doesn't say anything about who is doing the infecting.
>
> The actual number of fully vaccinated people is 41,157.069 out of a population of about 68 million - 60%.
>
> It may be 75% of the adults, but delta does seem to be infecting kids, and they can infect other people.

It depends a lot on how old they are - primary school children
apparently can dispose of the Covid virus without ever becoming PCR test
positive. I have posted the links before because it surprised me.

https://www.nature.com/articles/d41586-020-03496-7

It is thought to be something to do with their superior innate response
of an untrained immune system to novel infections in early years.

A few get Kawasaki syndrome but no more so than with any other virus.

>>> They may be just as infectious while they are infected, though what seems to be be measured is virus counts on nose and throat swabs, but the duration of the infectious period also matters. They aren't going to become Typhoid Marys - she stayed infectious all her life, and was locked up for her last thirty years.
>>
>> That doesn't seem to make much difference in practice since not getting
>> sick at all means they interact much more than their sickly unvaccinated
>> counterparts. Both have massive viral loads in the early stages of the
>> infection and before any symptoms appear.
>
> They don't. If they had massive viral loads they'd have symptoms.

Israel's problems with Delta tend to suggest that I am right. They are
seeing high levels of population transmission despite a very large
proportion of their population already vaccinated. And the awkward
unvaccinated cohort there have probably all had Covid naturally by now.

https://www.sciencemag.org/news/2021/08/grim-warning-israel-vaccination-blunts-does-not-defeat-delta

Even in the UK London ultra orthodox community managed to get to 75%
Covid antibody positive by natural means. Massive weddings and ignoring
all the lockdown rules being the primary transmission vectors.

https://www.news-medical.net/news/20210207/Orthodox-Jewish-in-UK-disproportionately-impacted-by-COVID-19.aspx

>>>> Alpha and earlier variant transmission is almost stopped by vaccination.
>>
>> We will have to wait and see how it pans out.
>
> But misunderstanding what you are seeing now isn't a good start.

We will see.

--
Regards,
Martin Brown

On Friday, August 20, 2021 at 7:58:31 PM UTC+10, Martin Brown wrote:
> On 20/08/2021 09:36, Anthony William Sloman wrote:
> > On Friday, August 20, 2021 at 5:59:55 PM UTC+10, Martin Brown wrote:
> >> On 19/08/2021 15:54, Anthony William Sloman wrote:
> >>> On Thursday, August 19, 2021 at 6:21:14 PM UTC+10, Martin Brown
> >>> wrote:
> >>>> On 18/08/2021 04:21, Anthony William Sloman wrote:
> >>
> >>>> Oxford study has some more on Pfizer vs AZ vaccines against Delta.
> >>>> Pfizer wanes markedly from its initial high efficacy to about the
> >>>> same as AZ on about a 5 month timescale. It remains unclear what
> >>>> happens beyond that (although Isreal's 40% reported might be a
> >>>> hint).
> >>>
> >>> You have a habit of confusing antibody titres with efficacy.
> >>
> >> I have a great liking of quantitative things that can be measured.
> >
> > Less enthusiasm for working out whether what has been measured actually means what you'd like it to mean.
> >
> >> I know other parts of the immune system may provide some longer term
> >> immunity but it is beginning to look like Pfizer doesn't where AZ does..
> >
> > But what makes you think that?
> >
> >> Better Israeli data on this question of fading immunity should be
> >> available fairly soon - their preliminary results look worrying to me.
> >
> > Again, they seem to have been measuring antibody titres, rather than hospital admissions.
> >
> >>>> https://www.ndm.ox.ac.uk/covid-19/covid-19-infection-survey/results/new-studies
> >>>>
> >>>> Delta makes vaccinated people just as infectious as unvaccinated ones.
> >>>
> >>> For a short while - they don't seem to stay infected or infectious
> >>> for all that long, which means that from the point of view of
> >>> infecting other people they aren't as infectious as the unvaccinated.
> >>
> >> UK transmission levels at the moment suggest that isn't true. The levels
> >> of Covid infection are stable but relatively high at 30k/day. And about
> >> equally split across vaccinated people (>75% adults) and unvaccinated.
> >>
> >> https://www.bbc.co.uk/news/uk-51768274
> >
> > Which doesn't say anything about who is doing the infecting.
> >
> > The actual number of fully vaccinated people is 41,157.069 out of a population of about 68 million - 60%.
> >
> > It may be 75% of the adults, but delta does seem to be infecting kids, and they can infect other people.
> It depends a lot on how old they are - primary school children
> apparently can dispose of the Covid virus without ever becoming PCR test
> positive. I have posted the links before because it surprised me.
>
> https://www.nature.com/articles/d41586-020-03496-7
>
> It is thought to be something to do with their superior innate response
> of an untrained immune system to novel infections in early years.
>
> A few get Kawasaki syndrome but no more so than with any other virus.
> >>> They may be just as infectious while they are infected, though what seems to be be measured is virus counts on nose and throat swabs, but the duration of the infectious period also matters. They aren't going to become Typhoid Marys - she stayed infectious all her life, and was locked up for her last thirty years.
> >>
> >> That doesn't seem to make much difference in practice since not getting
> >> sick at all means they interact much more than their sickly unvaccinated
> >> counterparts. Both have massive viral loads in the early stages of the
> >> infection and before any symptoms appear.
> >
> > They don't. If they had massive viral loads they'd have symptoms.
>
> Israel's problems with Delta tend to suggest that I am right.

Most evidence suggests to you that you are right. More objective observers have other opinions.

> They are seeing high levels of population transmission despite a very large
> proportion of their population already vaccinated. And the awkward
> unvaccinated cohort there have probably all had Covid naturally by now.
>
> https://www.sciencemag.org/news/2021/08/grim-warning-israel-vaccination-blunts-does-not-defeat-delta

78% fully vaccinated doesn't seem to be high enough to guarantee herd immunity. When you have rabid ultra-orthodox vaccine rejectors to deal with, the 22% un-vaccinated may be well placed to pass the infection on to their neightbours.
> Even in the UK London ultra orthodox community managed to get to 75% Covid antibody positive by natural means. Massive weddings and ignoring all the lockdown rules being the primary transmission vectors.

And being immune from natural infection by the original strain doesn't provide the sort of protection against more recent strains which exposure to just the highly conserved spike protein from a vaccine can provide.
> https://www.news-medical.net/news/20210207/Orthodox-Jewish-in-UK-disproportionately-impacted-by-COVID-19.aspx
>
> >>>> Alpha and earlier variant transmission is almost stopped by vaccination.
> >>
> >> We will have to wait and see how it pans out.
> >
> > But misunderstanding what you are seeing now isn't a good start.
>
> We will see.

True. But misunderstandings can be expensive.

--
Bill Sloman, Sydney