Dumping toxicity on us all. Breathtaking arrogance.
GiggidyGoo
Micheal Martin’s lack of abilities has been a major contributor to their downfall. His pursuit of the personal goal of having “Taoiseach” on a business card has cost FF big time.
GiggidyGoo
TA
GiggidyGoo
Trickle Hogan and Rub-my-hands-with-glee Calleary and no doubt some more folk talcum-powder-smelling-underwear stalwarts of FFG have just told us, yet again, “ Do as I say, not as I do”.
Calleary has admitted he knew it was a breach of the rules but went ahead and did it anyway.
He is the minister for agriculture and food. His pronouncements relating to meat factories versus his own actions makes his position untenable. As is Bully-buy Hogan’s.
I wonder will Sean O’Rourke get a mention on Sarah McInerny’s show this morning? Maybe even an interview.
The Irish Times, when O’Rourke retired informed us “Sean O’Rourke’s final show reminds listeners why he’ll be missed”, should have spelt it out more clearly. It’s the politicians who will miss him. And guess what? His permanent replacement is similar.
Clampers Outside
Isn’t Claire Byrne in Sarah’s seat now… Sarah was only there for the summer.
Haven’t tuned in this week, it’s been on but not heard, if ya get me
Johnny Green
Steve just now outside court.
“This entire fiasco is to stop people who want to build the wall.”
Its a lot more than a million-WSJ has the real story.
“… Federal and state authorities are investigating a media company linked to Mr. Bannon and exiled Chinese businessman Guo Wengui that raised more than $300 million in a private offering this spring, The Wall Street Journal reported ..”
As they expect these charges to be viciously attacked by the MAGNA crowd,the prosecutors went into detail in the release,if he’s convicted on half these mail fraud charges,it’s 20 years,these prosecutors have a 95% success rate.
Steve was arrested on board Guo’s yacht this morning,he’s out now on very restricted bail,incredible amount news coverage all damming,the democratic challenger is accepting his nomination this evening.
Gerry
Holiday in the heart for me today, it will be interesting to see these guys squirm as they try to defend the exorbitant “fees” they charged, while claiming they were unpaid. Middle America might be gullible, but they hate lying and stealing.
It will be interesting to compare the fund’s border wall contribution to the amounts extracted by Bannon & Co. Anyone prepared to bet the wall contribution is bigger? Not me!
Nigel
BOOM as I believe it is culturally appropriate to expostulate in certain online venues.
Johnny Green
Bada Bing (strip club The Sopranos.) running with the stripper theme.
The wax on Steve’s wings,finally melted in Alabama,losing a seat that never should have ever,even been in play (Roy Moore),that’s unforgivable.It’s like Man U losing to Shamrock Rovers at Old Trafford,can happen but,he was the manager,Mercer’s his backers cut him lose,hence the podcast from his basement,dodgy deals.
He was already on the outs with Kushner,who he despises and took a few shots in Wolff’s book,describing Trump Org as a criminal enterprise,not much love for Steve in MAGA world,after he was star witness against Stone,snitches get stitches,culture,bada bing.
RNC next week-contrast will be interesting,when you create a caricature of your opponent,invoking senility and mental competence,it can have the unintended effect of setting the bar very low.
Says yer man Dennis O’Briens b*tch,who parlayed a minor role in the GFA into access to major Dems for DOB,pimping out his contacts,cost him…..haha still keeping the Ambassador dream alive-huh.
‘As the arrest of Steve Bannon proved yesterday the corruption surrounding the White House among Donald Trump’s charmed circle is massive. We have the most immoral gang of characters in power who have more in common with a banana republic than the world’s greatest democracy.’
This from RTE yesterday: https://twitter.com/rtenews/status/1296517739083948032
“Dr Derval Igoe, Principal Investigator for the study to investigate Covid-19 in the population, says through the study they have been able to estimate a national (antibody) prevalence rate of 1.7%, meaning less than 2 in every 100 people have been infected”
It’s hard to fathom what’s going on here. The most generous explanation is that it’s misinformation but considering the wealth of scientific evidence that has already emerged about the key role of the longer-lasting T-Cell response in fighting Covid infection, its hard not see it as anything other than deliberate disinformation. Even our own media has published articles about this key role T-Cells play. In cases where a person generates antibodies to fight the infection, it’s known that the antibodies disappear after a few months while the T Cells remains in place much longer, potentially years
Rosemary Boyton and Daniel Altmann, professors of immunology at Imperial College London, said: “If, as appears the case, measuring T-cell immunity is a more enduring and reliable marker of adaptive immunity in COVID-19 than antibody, it will be valuable to achieve rollout for health services of commercial T-cell testing kits.”
“At the start of the pandemic, a key mantra was that we needed the game-changer of antibody data to understand who had been infected and how many were protected.
“As we have learnt more about this challenging infection, it’s time to admit that we really need the T cell data too.”
According to a recent BBC article a 24hr T-Cell test has just been developed in the UK.
What does anyone make of the statement by Dr Derval Igoe? I find it very strange.
alickdouglas
This is a big topic, I’ll attempt to be brief.
Not wild about the SCOPI study because of the low number of participants; only about 35% of people responded, and they were unbalanced for age group so they have only 33 positive cases in total in Dublin and Sligo if I read it right. I understand why they went on to report percentages and CIs, but they could just have well have said 5 seropositive in Sligo and 28 in Dublin… Nevertheless, the reporting is clear enough in their online pre-pub, and I don’t see any red flags for methodology. Plus I imagine they followed a similar methodology to other EEA countries so allows them to compare via ECDC.
However, I suspect that you are querying the measure they investigated. This is an angry wasps nest of a topic, but it’s not nearly as controversial as many corners of the media try to portray it. While I’m not working on COVID (praise be), I’ve been heavily involved in the ‘serological vs cellular immune response’ discussion for nearly 20 years. Both are important, but their application is different, in a large part because of non-scientific factors such as the cost per test, their availability and the degree to which the output needs scientific interpretation. You can perhaps think of serology assays as testing akin to x-ray and cellular assays as CAT scans. The CAT scan gives a lot more data, but it is a lot more costly, much more difficult to interpret, and is much more time consuming. I don’t know the current costs, but serology tests are typically a few $ per kit. Cellular tests usually aren’t kits, need to be done by an experienced technician and validated by a very experienced team lead. Each cell type you want to test needs a different readout, and they are a couple of hundred $ per test. Worst of all, last time I looked (less than a year ago) all the tests had a heavy qualitative element to them, and so need to be re-run with disturbing frequency.
Ultimately, the test used should be determined by the research question. For SCOPI it looks like the study question was ‘what proportion of the population has been exposed’. They question was not ‘how many people are protected against …’ (and cellular testing wouldn’t reveal that anyway).
SOQ
alickdouglas- just to check- serological = anti bodies and cellular = T-cells?
Is it not the case that once a person has cleared CoVid-19, a number of different types of anti bodies are produced, each with a different life span up to about 56 days and by the end, the T Cells should be up and running?
I agree with f_lawless. Dr Derval Igoeis is either deliberately misleading the public otherwise why not mention T Cells which are the main long term immunity?
People who were infected with SARS-CoV-1 have immunity for 17 years and counting- is there any reason to assume the same will not occur with SARS-Cov-2?
Also, given that there are over 30 types of Coronavirses, why is HSE website now using the term Cromonavirus rather than CoVid-19 or SARS_Cov-2- which one are they referring to exactly?
SOQ
I really should type my points out properly before the edit clock starts because I always miss something and it ends up looking jumbled.
alickdouglas
As you note, I also missed the edit clock; I should have said ‘humoral vs cellular’ not ‘serological vs. cellular’. But yes, I was short-handing antibodies to be serum and cells to be whole blood because that’s what you need for the tests (essentially).
OK we are beginning our walk into the swamp of complexity here, but I’ll try to stay on track; also I don’t regard myself as a subject matter expert on this topic, but have worked with people who are.
There is a fundamental, and usually ignored difference between humoral and cellular immune response evaluation. In short, humoral testing is (relatively) easy, repeatable and comparable. This is why antibody ‘kits’ exist. (slight deviation here, kits are not easy things to make nor use, but they come with a set protocol which should mean that if you do a test with an abbott kit in Sligo, you should get a comparable result out of an abbott kit done in a lab in Copenhagen. Labs usually need certified staff [not necessarily to PhD level] to conduct them, and are likely to meet some internationally recognised standard for testing with kits). Cellular testing on the other hand is complex for a host of reasons. For a start, humoral testing can be done with serum. It’s extracted from blood, but once that’s done it’s pretty stable and means it doesn’t need careful treatment between the subject and the test center. Cellular testing needs to be done with whole blood. Most places that I’ve worked with that do cellular testing have a lab on the same site that the patients come to. You can freeze the samples, but logistically it’s a nightmare compared with serum. The testing of the samples is not straightforward, and there are many quantitative aspects to the readout. Because of this, cellular samples are not standardizable in the same way as humoral tests, so valid comparability comparison is not straightforward (it is possible, but it is a giant pain in the bottom).
So returning to the SCOPI paper, for the question they were investigating, humoral testing was the right choice; they wanted value for money, and I guess to be able to compare with other countries. This is absolutely what I would expect from the state lab. Even if the state lab could run a few cellular tests I doubt that they could do hundreds of tests (from the staffing, logistics, material or financial perspective). Happy to be shown to be wrong on that one if someone knows better.
The question of who is protected is an entirely different one, and is outside the scope of almost any state laboratory I can think of. NIH in the US could probably pursue it, but they would more likely prefer an industry funded research center to do it–think Oxford or Harvard.
Returning then to the Oxford kits mentioned in the paper. They don’t exist yet. They need to be validated, manufactured, available, this will all take time. I’ve had extremely painful experiences due to poor quality control of kits for simple tests made by big manufacturers. I’m sceptical that these validation and manufacturing problems will be ironed out any time soon.
f_lawless
Thanks for your responses alickdouglas and SOQ .
I still unsure how testing for the presence of antibodies is an appropriate way to determine with any degree of accuracy what proportion of the population has been exposed to the virus.
1. If antibodies are generally only detectable for a number of weeks up to three months maximum, then wouldn’t it be true that those people who were exposed more than three months ago (when the pandemic was at its height) would likely go undetected in the recent study?
2. All the people whose immune system didn’t generate antibodies while fighting off the virus would similarly go undetected in the study
alickdouglas
F_ cannot respond to your post, so I have to respond to my own… So I want to be clear on the difference between exposure and infection, as I think I may also have mis-used it earlier. You can be exposed to a virus without being ‘infected’, and in that case, there aren’t going to be any biomarkers. Physical barriers (skin, mucus), and innate factors like natural killer cells, plus the fact that some viruses are not viable, can all mean that a person can be heavily exposed, but not become infected. In that case, I guess you might be PCR-positive, but no biomarker test will reveal you’ve been exposed.
Typically, if the pathogen gets through the innate system, it is up to the ‘adaptive’ immune system of humoral and cell-mediated responses to tackle it. As you imply, the antibodies are usually seen in the greatest amounts early in infection. I’m not aware of any viral pathogen where an infection does not lead to an increase in pathogen-specific antibodies. For me, and in response to your point 2) if you don’t have any antibodies then you’ve not been *infected* (there are caveats here, perhaps the test didn’t work, perhaps the blood sample wasn’t handled right, or perhaps you didn’t take the sample at a time when antibody action was prevalent). There are probably case studies, which show interesting exceptions, but I think the vast majority of people only mount a cell-mediated immune response in partnership with a humoral antibody response.
When it comes to your first point, I’ve not stayed up to date with COVID: it may be that for some people the antibodies fade to nothing after 3 months, but I don’t believe this to be typical. Furthermore, while it is possible for people to have antibodies below the test cut off, I think that this is atypical. Antibodies don’t go away, they just fade to low levels. If memory serves the most common Hep B test has a cut off of about 1 or 2 international units, and you are judged protected if you have 10. Vaccinated people typically rest at about 12 international units 5 years after vaccination, dropping from 100 to 1000 units in the weeks following infection (when you see the data you think ‘oh gosh, 12 looks very low).
There is a major secondary headache with this conversation which is that ‘detectability’ depends on the specifications and parameters of the test (kit) you are using. It may be that the (for example) Abbott test kit isn’t sensitive at the low end, but if you are a lab leader, you can surely find or implement a different antibody test that will detect very low levels of antibodies. However, again it depends on what you are trying to measure.
SOQ
Tnx @alickdouglas – so the T-cell tests are more complicated and expensive- and provided by private labs only? And- that the quality of anti-body tests may vary or that people may have a lower anti-body load than a particular test may register?
@f_lawless- I agree- irrespective of the expertise and expense of T-Cell testing, it should have at least have been pointed out that anti-bodies are not the only tool in the immune system’s kit. And then there is the issue of cross immunity- we know for example that immunity to SARS-Cov-1 offers some protection and perhaps from some other Coronaviruses too.
alickdouglas
SOQ: Yes, cellular testing is usually done by people who can justify invoicing for it. It’s much more ’boutique’ and academic. I’m not really aware of typical health situations that would warrant large scale cellular immunity testing, so state labs aren’t set up for it, either from an infrastructure perspective or an intellectual capacity. The actual market demand for cellular testing is extremely limited. Regulators (FDA) have always leaned on antibody testing for the licensure of vaccines and biologics (although most are licensed on efficacy vs. disease and safety profile, with immune response regarded as supportive). Cellular testing is a nice cherry to demonstrate the breadth of immune response elicited by a treatment, but it’s not regarded by FDA as a licensure criterion for any product that I can think of. Therefore there’s a much stronger financial incentive to develop antibody testing (it’s easier, and the market wants it) than cellular testing (academically interesting).
SOQ
Tnx @alickdouglas – the sensitivity of the test resonates because I know of several people who recently tested positive for a previous infection of Hepatitis C.
It was quite a shock in both cases as nether were in what is known as high risk groups- IV drugs use, blood transfusions, tattoos etc and neither knew they had been infected.
In both cases it was a standard STI screen and the reason given was that the sensitivity of the Hepatitis C test had improved. Of course Hep C is not like B- there is no long term immunity to it and reinfection can occur.
I suppose the core point here is that virus testing is not an absolute one way or another and that is always a margin of error for the reasons you have outlined above.
Tnx for your input- it certainly has a cleared a few things up- at least for me.
Clampers Outside
Thanks F_ and Alick… Interesting posts
Lush
+1.
Very informative.
GiggidyGoo
Any Laois, Offaly, Kildare TDs in attendance?
GiggidyGoo
Actually, when you count staff at the function (which have to be taken into account I believe) then the numbers are north of 100. Was there entertainment?
Think now – how many couples had to cancel their weddings due to these rules?
And Calleary was at the NPHET meeting where the numbers were decided and then took off to, knowingly, break those rules.
And the Irish Hotels Federation can give instructions on what can, and can’t go ahead – a room split in two (my donkey) – did Calleary have to make his speech twice?
Bottler
Listened to a smug Aodhan O’Riordan this morning commenting on golf societies. He has carved out for himself a comfortable living trumpeting the woes of inner city schools and deprivation. Nothing achieved however.
Johnny Green
Hello…buenos días.
Alexandria Ocasio-Cortez on Self-Love, Fighting the Power, and Her Signature Red Lip.
Dara Calleary is a goner. Dear mam walking.
Outrageous… any elected politician in attendance should lose their portfolio/whip/front bench status.
“Qu’ils mangent de la brioche…” – Marie Antoinette
“Lig dóibh cáca a ithe…” – FFG
@ Otis Blue: bravissimo
FF have lost the magic touch for sure. I reckon they are on their way to becoming a bit player from now on. Capable of 12 to 20 TDs. No more.
Dumping toxicity on us all. Breathtaking arrogance.
Micheal Martin’s lack of abilities has been a major contributor to their downfall. His pursuit of the personal goal of having “Taoiseach” on a business card has cost FF big time.
TA
Trickle Hogan and Rub-my-hands-with-glee Calleary and no doubt some more folk talcum-powder-smelling-underwear stalwarts of FFG have just told us, yet again, “ Do as I say, not as I do”.
Calleary has admitted he knew it was a breach of the rules but went ahead and did it anyway.
He is the minister for agriculture and food. His pronouncements relating to meat factories versus his own actions makes his position untenable. As is Bully-buy Hogan’s.
I wonder will Sean O’Rourke get a mention on Sarah McInerny’s show this morning? Maybe even an interview.
The Irish Times, when O’Rourke retired informed us “Sean O’Rourke’s final show reminds listeners why he’ll be missed”, should have spelt it out more clearly. It’s the politicians who will miss him. And guess what? His permanent replacement is similar.
Isn’t Claire Byrne in Sarah’s seat now… Sarah was only there for the summer.
Haven’t tuned in this week, it’s been on but not heard, if ya get me
Steve just now outside court.
“This entire fiasco is to stop people who want to build the wall.”
Its a lot more than a million-WSJ has the real story.
“… Federal and state authorities are investigating a media company linked to Mr. Bannon and exiled Chinese businessman Guo Wengui that raised more than $300 million in a private offering this spring, The Wall Street Journal reported ..”
https://www.wsj.com/articles/former-senior-trump-advisor-steve-bannon-charged-with-alleged-fundraising-scheme-11597931727?mod=trending_now_pos1
As they expect these charges to be viciously attacked by the MAGNA crowd,the prosecutors went into detail in the release,if he’s convicted on half these mail fraud charges,it’s 20 years,these prosecutors have a 95% success rate.
Steve was arrested on board Guo’s yacht this morning,he’s out now on very restricted bail,incredible amount news coverage all damming,the democratic challenger is accepting his nomination this evening.
Holiday in the heart for me today, it will be interesting to see these guys squirm as they try to defend the exorbitant “fees” they charged, while claiming they were unpaid. Middle America might be gullible, but they hate lying and stealing.
It will be interesting to compare the fund’s border wall contribution to the amounts extracted by Bannon & Co. Anyone prepared to bet the wall contribution is bigger? Not me!
BOOM as I believe it is culturally appropriate to expostulate in certain online venues.
Bada Bing (strip club The Sopranos.) running with the stripper theme.
The wax on Steve’s wings,finally melted in Alabama,losing a seat that never should have ever,even been in play (Roy Moore),that’s unforgivable.It’s like Man U losing to Shamrock Rovers at Old Trafford,can happen but,he was the manager,Mercer’s his backers cut him lose,hence the podcast from his basement,dodgy deals.
He was already on the outs with Kushner,who he despises and took a few shots in Wolff’s book,describing Trump Org as a criminal enterprise,not much love for Steve in MAGA world,after he was star witness against Stone,snitches get stitches,culture,bada bing.
RNC next week-contrast will be interesting,when you create a caricature of your opponent,invoking senility and mental competence,it can have the unintended effect of setting the bar very low.
Says yer man Dennis O’Briens b*tch,who parlayed a minor role in the GFA into access to major Dems for DOB,pimping out his contacts,cost him…..haha still keeping the Ambassador dream alive-huh.
‘As the arrest of Steve Bannon proved yesterday the corruption surrounding the White House among Donald Trump’s charmed circle is massive. We have the most immoral gang of characters in power who have more in common with a banana republic than the world’s greatest democracy.’
https://www.irishcentral.com/opinion/niallodowd/joe-biden-crushes-it-acceptance-speech
This from RTE yesterday:
https://twitter.com/rtenews/status/1296517739083948032
“Dr Derval Igoe, Principal Investigator for the study to investigate Covid-19 in the population, says through the study they have been able to estimate a national (antibody) prevalence rate of 1.7%, meaning less than 2 in every 100 people have been infected”
It’s hard to fathom what’s going on here. The most generous explanation is that it’s misinformation but considering the wealth of scientific evidence that has already emerged about the key role of the longer-lasting T-Cell response in fighting Covid infection, its hard not see it as anything other than deliberate disinformation. Even our own media has published articles about this key role T-Cells play. In cases where a person generates antibodies to fight the infection, it’s known that the antibodies disappear after a few months while the T Cells remains in place much longer, potentially years
From July: https://www.irishexaminer.com/world/arid-40017881.html
Rosemary Boyton and Daniel Altmann, professors of immunology at Imperial College London, said: “If, as appears the case, measuring T-cell immunity is a more enduring and reliable marker of adaptive immunity in COVID-19 than antibody, it will be valuable to achieve rollout for health services of commercial T-cell testing kits.”
“At the start of the pandemic, a key mantra was that we needed the game-changer of antibody data to understand who had been infected and how many were protected.
“As we have learnt more about this challenging infection, it’s time to admit that we really need the T cell data too.”
According to a recent BBC article a 24hr T-Cell test has just been developed in the UK.
What does anyone make of the statement by Dr Derval Igoe? I find it very strange.
This is a big topic, I’ll attempt to be brief.
Not wild about the SCOPI study because of the low number of participants; only about 35% of people responded, and they were unbalanced for age group so they have only 33 positive cases in total in Dublin and Sligo if I read it right. I understand why they went on to report percentages and CIs, but they could just have well have said 5 seropositive in Sligo and 28 in Dublin… Nevertheless, the reporting is clear enough in their online pre-pub, and I don’t see any red flags for methodology. Plus I imagine they followed a similar methodology to other EEA countries so allows them to compare via ECDC.
However, I suspect that you are querying the measure they investigated. This is an angry wasps nest of a topic, but it’s not nearly as controversial as many corners of the media try to portray it. While I’m not working on COVID (praise be), I’ve been heavily involved in the ‘serological vs cellular immune response’ discussion for nearly 20 years. Both are important, but their application is different, in a large part because of non-scientific factors such as the cost per test, their availability and the degree to which the output needs scientific interpretation. You can perhaps think of serology assays as testing akin to x-ray and cellular assays as CAT scans. The CAT scan gives a lot more data, but it is a lot more costly, much more difficult to interpret, and is much more time consuming. I don’t know the current costs, but serology tests are typically a few $ per kit. Cellular tests usually aren’t kits, need to be done by an experienced technician and validated by a very experienced team lead. Each cell type you want to test needs a different readout, and they are a couple of hundred $ per test. Worst of all, last time I looked (less than a year ago) all the tests had a heavy qualitative element to them, and so need to be re-run with disturbing frequency.
Ultimately, the test used should be determined by the research question. For SCOPI it looks like the study question was ‘what proportion of the population has been exposed’. They question was not ‘how many people are protected against …’ (and cellular testing wouldn’t reveal that anyway).
alickdouglas- just to check- serological = anti bodies and cellular = T-cells?
Is it not the case that once a person has cleared CoVid-19, a number of different types of anti bodies are produced, each with a different life span up to about 56 days and by the end, the T Cells should be up and running?
I agree with f_lawless. Dr Derval Igoeis is either deliberately misleading the public otherwise why not mention T Cells which are the main long term immunity?
People who were infected with SARS-CoV-1 have immunity for 17 years and counting- is there any reason to assume the same will not occur with SARS-Cov-2?
Also, given that there are over 30 types of Coronavirses, why is HSE website now using the term Cromonavirus rather than CoVid-19 or SARS_Cov-2- which one are they referring to exactly?
I really should type my points out properly before the edit clock starts because I always miss something and it ends up looking jumbled.
As you note, I also missed the edit clock; I should have said ‘humoral vs cellular’ not ‘serological vs. cellular’. But yes, I was short-handing antibodies to be serum and cells to be whole blood because that’s what you need for the tests (essentially).
OK we are beginning our walk into the swamp of complexity here, but I’ll try to stay on track; also I don’t regard myself as a subject matter expert on this topic, but have worked with people who are.
There is a fundamental, and usually ignored difference between humoral and cellular immune response evaluation. In short, humoral testing is (relatively) easy, repeatable and comparable. This is why antibody ‘kits’ exist. (slight deviation here, kits are not easy things to make nor use, but they come with a set protocol which should mean that if you do a test with an abbott kit in Sligo, you should get a comparable result out of an abbott kit done in a lab in Copenhagen. Labs usually need certified staff [not necessarily to PhD level] to conduct them, and are likely to meet some internationally recognised standard for testing with kits). Cellular testing on the other hand is complex for a host of reasons. For a start, humoral testing can be done with serum. It’s extracted from blood, but once that’s done it’s pretty stable and means it doesn’t need careful treatment between the subject and the test center. Cellular testing needs to be done with whole blood. Most places that I’ve worked with that do cellular testing have a lab on the same site that the patients come to. You can freeze the samples, but logistically it’s a nightmare compared with serum. The testing of the samples is not straightforward, and there are many quantitative aspects to the readout. Because of this, cellular samples are not standardizable in the same way as humoral tests, so valid comparability comparison is not straightforward (it is possible, but it is a giant pain in the bottom).
So returning to the SCOPI paper, for the question they were investigating, humoral testing was the right choice; they wanted value for money, and I guess to be able to compare with other countries. This is absolutely what I would expect from the state lab. Even if the state lab could run a few cellular tests I doubt that they could do hundreds of tests (from the staffing, logistics, material or financial perspective). Happy to be shown to be wrong on that one if someone knows better.
The question of who is protected is an entirely different one, and is outside the scope of almost any state laboratory I can think of. NIH in the US could probably pursue it, but they would more likely prefer an industry funded research center to do it–think Oxford or Harvard.
Returning then to the Oxford kits mentioned in the paper. They don’t exist yet. They need to be validated, manufactured, available, this will all take time. I’ve had extremely painful experiences due to poor quality control of kits for simple tests made by big manufacturers. I’m sceptical that these validation and manufacturing problems will be ironed out any time soon.
Thanks for your responses alickdouglas and SOQ .
I still unsure how testing for the presence of antibodies is an appropriate way to determine with any degree of accuracy what proportion of the population has been exposed to the virus.
1. If antibodies are generally only detectable for a number of weeks up to three months maximum, then wouldn’t it be true that those people who were exposed more than three months ago (when the pandemic was at its height) would likely go undetected in the recent study?
2. All the people whose immune system didn’t generate antibodies while fighting off the virus would similarly go undetected in the study
F_ cannot respond to your post, so I have to respond to my own… So I want to be clear on the difference between exposure and infection, as I think I may also have mis-used it earlier. You can be exposed to a virus without being ‘infected’, and in that case, there aren’t going to be any biomarkers. Physical barriers (skin, mucus), and innate factors like natural killer cells, plus the fact that some viruses are not viable, can all mean that a person can be heavily exposed, but not become infected. In that case, I guess you might be PCR-positive, but no biomarker test will reveal you’ve been exposed.
Typically, if the pathogen gets through the innate system, it is up to the ‘adaptive’ immune system of humoral and cell-mediated responses to tackle it. As you imply, the antibodies are usually seen in the greatest amounts early in infection. I’m not aware of any viral pathogen where an infection does not lead to an increase in pathogen-specific antibodies. For me, and in response to your point 2) if you don’t have any antibodies then you’ve not been *infected* (there are caveats here, perhaps the test didn’t work, perhaps the blood sample wasn’t handled right, or perhaps you didn’t take the sample at a time when antibody action was prevalent). There are probably case studies, which show interesting exceptions, but I think the vast majority of people only mount a cell-mediated immune response in partnership with a humoral antibody response.
When it comes to your first point, I’ve not stayed up to date with COVID: it may be that for some people the antibodies fade to nothing after 3 months, but I don’t believe this to be typical. Furthermore, while it is possible for people to have antibodies below the test cut off, I think that this is atypical. Antibodies don’t go away, they just fade to low levels. If memory serves the most common Hep B test has a cut off of about 1 or 2 international units, and you are judged protected if you have 10. Vaccinated people typically rest at about 12 international units 5 years after vaccination, dropping from 100 to 1000 units in the weeks following infection (when you see the data you think ‘oh gosh, 12 looks very low).
There is a major secondary headache with this conversation which is that ‘detectability’ depends on the specifications and parameters of the test (kit) you are using. It may be that the (for example) Abbott test kit isn’t sensitive at the low end, but if you are a lab leader, you can surely find or implement a different antibody test that will detect very low levels of antibodies. However, again it depends on what you are trying to measure.
Tnx @alickdouglas – so the T-cell tests are more complicated and expensive- and provided by private labs only? And- that the quality of anti-body tests may vary or that people may have a lower anti-body load than a particular test may register?
@f_lawless- I agree- irrespective of the expertise and expense of T-Cell testing, it should have at least have been pointed out that anti-bodies are not the only tool in the immune system’s kit. And then there is the issue of cross immunity- we know for example that immunity to SARS-Cov-1 offers some protection and perhaps from some other Coronaviruses too.
SOQ: Yes, cellular testing is usually done by people who can justify invoicing for it. It’s much more ’boutique’ and academic. I’m not really aware of typical health situations that would warrant large scale cellular immunity testing, so state labs aren’t set up for it, either from an infrastructure perspective or an intellectual capacity. The actual market demand for cellular testing is extremely limited. Regulators (FDA) have always leaned on antibody testing for the licensure of vaccines and biologics (although most are licensed on efficacy vs. disease and safety profile, with immune response regarded as supportive). Cellular testing is a nice cherry to demonstrate the breadth of immune response elicited by a treatment, but it’s not regarded by FDA as a licensure criterion for any product that I can think of. Therefore there’s a much stronger financial incentive to develop antibody testing (it’s easier, and the market wants it) than cellular testing (academically interesting).
Tnx @alickdouglas – the sensitivity of the test resonates because I know of several people who recently tested positive for a previous infection of Hepatitis C.
It was quite a shock in both cases as nether were in what is known as high risk groups- IV drugs use, blood transfusions, tattoos etc and neither knew they had been infected.
In both cases it was a standard STI screen and the reason given was that the sensitivity of the Hepatitis C test had improved. Of course Hep C is not like B- there is no long term immunity to it and reinfection can occur.
I suppose the core point here is that virus testing is not an absolute one way or another and that is always a margin of error for the reasons you have outlined above.
Tnx for your input- it certainly has a cleared a few things up- at least for me.
Thanks F_ and Alick… Interesting posts
+1.
Very informative.
Any Laois, Offaly, Kildare TDs in attendance?
Actually, when you count staff at the function (which have to be taken into account I believe) then the numbers are north of 100. Was there entertainment?
Think now – how many couples had to cancel their weddings due to these rules?
And Calleary was at the NPHET meeting where the numbers were decided and then took off to, knowingly, break those rules.
And the Irish Hotels Federation can give instructions on what can, and can’t go ahead – a room split in two (my donkey) – did Calleary have to make his speech twice?
Listened to a smug Aodhan O’Riordan this morning commenting on golf societies. He has carved out for himself a comfortable living trumpeting the woes of inner city schools and deprivation. Nothing achieved however.
Hello…buenos días.
Alexandria Ocasio-Cortez on Self-Love, Fighting the Power, and Her Signature Red Lip.
https://www.vogue.com/article/alexandria-ocasio-cortez-beauty-secrets?utm_brand=vogue&utm_source=twitter&utm_social-type=owned&mbid=social_twitter&utm_medium=social
sixty seconds
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