The Lemon Fool

johnhemming wrote:The antibodies fade (although immunity doesn't) so you would not necessarily make that much more progress.

I think it is best to start with the people who are most likely to die from the virus. After a point that will materially cut down on deaths from the virus.

Just been chosen at random notified for this antibody survey:-
https://www.ipsos.com/ipsos-mori/en-uk/ ... tests-faqs
Ipsos MORI and Imperial College London are conducting this research on behalf of the Department of Health and Social Care (DHSC), to help the Government develop its approach to COVID-19 testing.
As you may know, the Government is planning to introduce an antibody blood test to check whether people have had the virus. This study will help understand how many people in England have already been infected with the virus which causes COVID-19.

supremetwo wrote:Just been chosen at random notified for this antibody survey:-
https://www.ipsos.com/ipsos-mori/en-uk/ ... tests-faqs

They do know that the antibodies fade. It is still worth doing the tests, however. There are arguments about the lateral flow tests. However, I don't have a view about those arguments because I have not studied them enough.

Article in Science on Manaus and herd immunity. Paraphrased as "What would happen if we just let the virus go & lifted all restrictions & had a largely uncontrolled COVID-19 epidemic? Mass death."

https://science.sciencemag.org/content/ ... 30/tab-pdf

Scott.

I have been doing a little research on the current situation in Manaus.

Last year there was a study which concluded that over 76% of the population had been infected by Covid in Manaus. In a city of 2.4 million about 1% have died. That would give an IFR of 0.13.

My own personal view on the IFR is that in spring/summer it ranges between 0.2 and 0.3 and is higher in the autumn/winter. Hence I think the IFR figure is too low.

There have been further deaths in Manaus more recently which indicates that either there is no herd immunity, there is a new variant for which prior immunity does not matter or the previously calculated/measured seroprevalence rate is wrong.

Unsurprisingly the government have responded in a precautionary manner to the second of these options. I do not criticise them for this.

Noting this report
https://www.npr.org/sections/goatsandso ... 0700752749

And the referenced report.
https://www.thelancet.com/journals/lang ... 14-109X(20)30387-9/fulltext#seccestitle10

It is clear that there are conflicting figures as to what the seroprevalence actually was.

Having looked at these I would think that the originally "measured" value is in fact an over statement.

johnhemming wrote:Having looked at these I would think that the originally "measured" value is in fact an over statement.

New article by Buss et al here with more numbers than I can take in in a quick scan https://science.sciencemag.org/content/371/6526/288, but it seems to support the 76% figure.

Scott.

Clitheroekid wrote:I've said before that prioritising very old people, who can easily be shielded from CV, at the expense of younger people who are facing the public, and are therefore at much higher risk, is stupid and misguided.

I've now heard from the BBC that if you've already had CV it gives you 83% immunity against catching it again.

Would it not therefore be sensible to exclude everyone who's already tested positive for CV from the first round of vaccinations, so that they could be instead given to people who haven't (or more accurately haven't knowingly) already had CV?

Taking it a step further, would it not be sensible to test everyone before vaccinating them and limit the scarce vaccinations to those who test negative?

Old people shielding didn't work very well, a lot of them have social and health care visitors on a daily or at least regularly. It should work in theory but it breaks down at the weakest link in the chain. A lot of social care is provided by low paid workers who often have life styles which aren't conducive to avoiding infection. They may live in crowded accomodation or have young family, they also visit a lot of people during their working day. It's not just old people you have to shield there are other categories of very high risk people including cancer patients with suppressed immune systems.

Younger people don't generally die from covid and there are less ending up in hospital. It's the high risk groups who put pressure on the NHS and the whole point of the exercise is to avoid swamping it.

Not vaccinating people who have had covid is a reasonable suggestion. We don't know how long the immunity lasts, 5 months @ 83% is the latest figure, it may well be longer, it probably is. Is there a database of those who have tested positive with the swab test? There should be, do they take ID from those taking the tests? Someone who has had the test might enlighten us.

I have just received an invitation from Imperial College, in association with the DHSC, NHS and Ipsos MORI, to take an antibody test, which will be a finger prick DIY test. They are looking for those who have already been infected. I am interested to see what it shows up. It says that the test is not 100% vaccurate at an individual level.

Presumably it looks for the presence of antibodies from whatever cause.

TJH

tjh290633 wrote:I have just received an invitation from Imperial College, in association with the DHSC, NHS and Ipsos MORI, to take an antibody test, which will be a finger prick DIY test. They are looking for those who have already been infected. I am interested to see what it shows up. It says that the test is not 100% vaccurate at an individual level.

Presumably it looks for the presence of antibodies from whatever cause.

TJH

It will probably be one of the antibody tests that detects the presence of SARS-Cov2 antibodies which they can do to a high degree of specificity. Their sensitivity can be less accurate.

See here

https://www.bmj.com/content/370/bmj.m3325

redsturgeon wrote:

tjh290633 wrote:I have just received an invitation from Imperial College, in association with the DHSC, NHS and Ipsos MORI, to take an antibody test, which will be a finger prick DIY test. They are looking for those who have already been infected. I am interested to see what it shows up. It says that the test is not 100% vaccurate at an individual level.

Presumably it looks for the presence of antibodies from whatever cause.

TJH

It will probably be one of the antibody tests that detects the presence of SARS-Cov2 antibodies which they can do to a high degree of specificity. Their sensitivity can be less accurate.

See here

https://www.bmj.com/content/370/bmj.m3325

Thanks. An interesting paper.

TJH

"Antibody testing should be undertaken at least two weeks after onset of symptoms"

What exactly does that mean? Sounds rather ominous.

Bouleversee wrote:"Antibody testing should be undertaken at least two weeks after onset of symptoms"

What exactly does that mean? Sounds rather ominous.

If you are looking for antibodies, it is best to do so when they are likely to be present. By their very nature there won't be there before infection, or at time infection, but afterwards once the body has been producing them to fight that infection.

They are possible to be present in those who had infection, and the body produced them to fight it off, without at any point the individual knowing about the infection, or displaying symptoms.

Apols. again. I must need new specs. I read it as "anybody testing etc." and when I realised my mistake I found I couldn't delete.

johnhemming wrote:In a city of 2.4 million about 1% have died. That would give an IFR of 0.13.

Sorry typographical error about 0.1% have died. I have since seen an excess deaths figure of 0.15% which would give an IFR of .0197

The same conclusions arise, however.

sg31 wrote:Not vaccinating people who have had covid is a reasonable suggestion. We don't know how long the immunity lasts, 5 months @ 83% is the latest figure, it may well be longer, it probably is. Is there a database of those who have tested positive with the swab test? There should be, do they take ID from those taking the tests? Someone who has had the test might enlighten us.

I'm not suggesting that people who have had CV shouldn't be vaccinated at all - merely that they should be at the bottom of the list, as they already have a high degree of immunity, and scarce resources should be targeted at the most needy.

By the time their immunity fades away the people who really need / `deserve' the vaccine, such as the social workers you mentioned, will have been vaccinated and the people who have had CV previously can then receive theirs.

Incidentally, something else occurred to me - is there any reason why people who have been vaccinated should not now be free to mix with other people who have been vaccinated? I realise it's illegal as things stand, but should they perhaps now be exempted from lockdown to that extent? Most of them are elderly, and no doubt they would welcome the chance to mix with their equally elderly chums.

Clitheroekid wrote:Incidentally, something else occurred to me - is there any reason why people who have been vaccinated should not now be free to mix with other people who have been vaccinated? I realise it's illegal as things stand, but should they perhaps now be exempted from lockdown to that extent? Most of them are elderly, and no doubt they would welcome the chance to mix with their equally elderly chums.

There are doubts about the period between the 1st and 2nd jab departing from the trials so the Government will not risk that at present.

There is no date for a second appointment on the two cards I have seen. The leaflet says:- 'Continue to take recommended precautions to avoid infection'.

supremetwo wrote:

Clitheroekid wrote:Incidentally, something else occurred to me - is there any reason why people who have been vaccinated should not now be free to mix with other people who have been vaccinated? I realise it's illegal as things stand, but should they perhaps now be exempted from lockdown to that extent? Most of them are elderly, and no doubt they would welcome the chance to mix with their equally elderly chums.

There are doubts about the period between the 1st and 2nd jab departing from the trials so the Government will not risk that at present.

There is no date for a second appointment on the two cards I have seen. The leaflet says:- 'Continue to take recommended precautions to avoid infection'.

My 83 yr old mother had her first jab last Friday (08/01), and was given an appointment for April for 2nd jab. Pfizer vaccine.

Isn't there a question about the vaccines not stopping people still being transmitters of the virus, so there is not yet any data to support vaccinated people being able to mix?

B

supremetwo wrote:

Clitheroekid wrote:Incidentally, something else occurred to me - is there any reason why people who have been vaccinated should not now be free to mix with other people who have been vaccinated? I realise it's illegal as things stand, but should they perhaps now be exempted from lockdown to that extent? Most of them are elderly, and no doubt they would welcome the chance to mix with their equally elderly chums.

There are doubts about the period between the 1st and 2nd jab departing from the trials so the Government will not risk that at present.

There is no date for a second appointment on the two cards I have seen. The leaflet says:- 'Continue to take recommended precautions to avoid infection'.

This story in The Guardian suggests that a longer gap between doses actually makes them more effective! The currently recommended gaps are the gaps that were used in the trials.

Watis

Watis wrote:

supremetwo wrote:

Clitheroekid wrote:Incidentally, something else occurred to me - is there any reason why people who have been vaccinated should not now be free to mix with other people who have been vaccinated? I realise it's illegal as things stand, but should they perhaps now be exempted from lockdown to that extent? Most of them are elderly, and no doubt they would welcome the chance to mix with their equally elderly chums.

There are doubts about the period between the 1st and 2nd jab departing from the trials so the Government will not risk that at present.

There is no date for a second appointment on the two cards I have seen. The leaflet says:- 'Continue to take recommended precautions to avoid infection'.

This story in The Guardian suggests that a longer gap between doses actually makes them more effective! The currently recommended gaps are the gaps that were used in the trials.

Watis

That might be true for the AZN one but for the Pfizer the trials were for a 3 week gap which is now being changed to 12 weeks which does not please Pfizer or the WHO or some doctors.

I suppose those antibody tests mentioned by TJH will be to see whether they can spin it out a bit longer.

swill453 wrote:Article in Science on Manaus and herd immunity. Paraphrased as "What would happen if we just let the virus go & lifted all restrictions & had a largely uncontrolled COVID-19 epidemic? Mass death."

https://science.sciencemag.org/content/ ... 30/tab-pdf

"Mass" death sounds terrible but what I have been reading for a few months now is that the death rate per 1,000 people who contract the virus is about 3.

So if all 65 million people in the UK caught the virus we would have 200,000 or so deaths. A large number for sure. But we are already at 100,000 anyway.

So I think "mass" there is a bit emotive. 64,800,000 Brits would survive.

BigB wrote:Isn't there a question about the vaccines not stopping people still being transmitters of the virus, so there is not yet any data to support vaccinated people being able to mix?

I wasn't suggesting that vaccinated people should be able to mix generally, just with other people who have been vaccinated, on the basis that the likelihood of them passing it to each other is very small, and outweighed by the social and other benefits that would accrue.