registerme
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Post by registerme on Sept 1, 2020 17:54:18 GMT
Why on earth go to the supermarket daily, especially if you're worried about the risks? Once a week works for me. Because otherwise (especially with pubs and restaurants etc not being open / people being less willing to go out and socialise etc) I'd barely leave the house. Bit of exercise, bit of fresh air, a coffee, the chance to decide what I want to eat that day rather than having to plan a week in advance (and a lot less food waste as a result)....
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Post by dan1 on Sept 1, 2020 19:53:24 GMT
registermeI've no idea regarding your questions. However, what you describe of casual contacts with those unknown to you is what I assumed the app was designed to track? Your known contacts (with family, with friends, down the pub, at the restaurant etc) will presumably let you know if they or one of their contacts had become sick with the virus. The other thing that comes to mind, and again I have no insight, are super spreaders.
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Post by Ton ⓉⓞⓃ on Sept 1, 2020 20:22:59 GMT
Apologies in advance, this will probably be poorly structured / not a clear question but.... help me understand something (probably directed at IFISAcava but would welcome anybody else's thoughts). The full UK lockdown started on the 23rd March. Five months ago and counting. Back at the beginning I'd go shopping every three or four days, picking up what was available. As the situation normalised I reverted to going daily, but observed social distancing where possible (ie queuing), but navigating supermarket aisles was... difficult. More recently, to observe the new rules / guidance, I've taken to wearing a mask when in a shop. Prior to the relaxation of the rules I didn't go out socialising once. Since the relaxation I have been out (though less than before) and have observed the rules (probably some blur around the edges when I've had one too many). I live in Lambeth, in London. In spite of all of the above I find it very hard to believe that I have had zero exposure to COVID-19. Just going to the supermarket daily probably sees me encounter more than a hundred people. The chances of me not encountering somebody who was asymptomatic prior to the lockdown must have been slim (especially given the number of people who now say they think they had it and that I met up with prior to lockdown). So a bunch of questions:- 1. Has any modelling been done on this? 2. What's the medical profession's view on required viral load necessary to cause an infection (presumably a range influenced by x, y and z)? 3. Does one virion entering my body mean I've been infected? 4. Related to 2 and 3. - can you be exposed and not be infected? 5. How much impact does personal hygiene / observing social distancing guidelines etc have on how infectious COVID-19 is? I guess some of my confusion arises around the definitions of exposure, infection, symptomatic, asymptomatic etc? Could I have stood in a queue for the supermarket 100 times and not encountered somebody who was infected? If they were infected (or n people were), would the fact that I was 2m away from them have eliminated the risk of infection (or reduced to a minimum)? The same when in a supermarket.... I just don't see how I could not have been exposed. Given that I don't see how I could not have been infected. Sorry, I did warn it was likely to ramble a bit .
These are the sort of questions that've interested me.
With literally one virion you are highly unlikely to get any disease whatever it is. It's normally hundreds or thousands of particles that do it. But I think you could say you've been exposed - but no one will ever know, there won't be any evidence, so only the virion will know about it.
With just one particle - it might get lost in the body and or destroyed by natural defences.
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registerme
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Post by registerme on Sept 1, 2020 21:32:48 GMT
registerme I've no idea regarding your questions. However, what you describe of casual contacts with those unknown to you is what I assumed the app was designed to track? Your known contacts (with family, with friends, down the pub, at the restaurant etc) will presumably let you know if they or one of their contacts had become sick with the virus. The other thing that comes to mind, and again I have no insight, are super spreaders. Is the app even generally available yet? If so, I'm... disappointed that I'd missed that (but which also begs the question how I missed it).
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Post by dan1 on Sept 1, 2020 21:43:34 GMT
registerme I've no idea regarding your questions. However, what you describe of casual contacts with those unknown to you is what I assumed the app was designed to track? Your known contacts (with family, with friends, down the pub, at the restaurant etc) will presumably let you know if they or one of their contacts had become sick with the virus. The other thing that comes to mind, and again I have no insight, are super spreaders. Is the app even generally available yet? If so, I'm... disappointed that I'd missed that (but which also begs the question how I missed it). Not that I know of but it's somewhat nugatory given there's so little trust left in this governments handling of the pandemic. Pre-Cummings I would have installed it but there's no way I'm given him (direct) access to my data now.
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Post by bracknellboy on Sept 2, 2020 6:42:42 GMT
..... 1. Has any modelling been done on this? 2. What's the medical profession's view on required viral load necessary to cause an infection (presumably a range influenced by x, y and z)? 3. Does one virion entering my body mean I've been infected? 4. Related to 2 and 3. - can you be exposed and not be infected? 5. How much impact does personal hygiene / observing social distancing guidelines etc have on how infectious COVID-19 is? I guess some of my confusion arises around the definitions of exposure, infection, symptomatic, asymptomatic etc? Could I have stood in a queue for the supermarket 100 times and not encountered somebody who was infected? If they were infected (or n people were), would the fact that I was 2m away from them have eliminated the risk of infection (or reduced to a minimum)? The same when in a supermarket.... I just don't see how I could not have been exposed. Given that I don't see how I could not have been infected. Sorry, I did warn it was likely to ramble a bit .
....
With literally one virion you are highly unlikely to get any disease whatever it is. It's normally hundreds or thousands of particles that do it. But I think you could say you've been exposed - but no one will ever know, there won't be any evidence, so only the virion will know about it.
With just one particle - it might get lost in the body and or destroyed by natural defences.
There was a very good program on BBC iPlayer about viruses, how they attack the body, how the body defends etc. This was originally pre-covid but was available a few months ago. unfortunately i couldn't find the link. If you had some spare time, might be worth searching for it.
Note: I have no medical knowledge and even less general knowledge, however that doesn't prevent me from surmising....:
Presumably you would only be deemed to be "infected" with a virus if the virion is successful in getting its core into one of your cells, and is successful in hijacking its reproductive capabilities so as to reproduce itself. Before then, there are a bunch of defence mechanism it has to get through, and in the case of the new "Big C" I think it has to successfully latch onto an ACE2 receptor. Also, and is where I may be particularly talking out of my backside, there are the T cells to think off. Their role is to kill off infected cells, thereby preventing the promuglation of reproduced virus from a hijacked cell: question is, can T cells detect and kill off even without virus specific immunity ? (there is quite a lot of discussion about role of T cells and C19)
So I think even with no specific immunity, a single virion is unlikely to get as far as being picked up and transported to a cell, let alone be successful in depositing its package. Also of course there is talk that maybe earlier exposure to some other coronaviruses might be imparting some level of immunity. If so, again you would expect that viral load might play a signifiicant role: small exposure, body might be able to defend against ?
Still, better to stay your distance, wear a mask, and wash your hands. Oh, and only go to the shops when others are not there.
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IFISAcava
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Post by IFISAcava on Sept 2, 2020 6:54:23 GMT
Data from careful study in Iceland gives an IFR of ... wait for it... 0.3% www.nejm.org/doi/full/10.1056/NEJMoa2026116?query=featured_homeThis is, of course, the figure Ionannidis has been viciously attacked for suggesting all those months ago. We should acknowledge that there is no one "true" IFR for the virus - it depends very much on age structure and general health of the population the virus infects. It will be higher in older unhealthy populations (the West) and lower in younger populations (developing world, current "second wave"). We should also beware of the tendency towards ad hominum attacks on people whose work doesn't agree with pre-formed views or beliefs. EDIT: also of note is that immunity did not drop off over the 4 months of the study (and in fact increased initially)
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benaj
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Post by benaj on Sept 2, 2020 12:59:47 GMT
Data from careful study in Iceland gives an IFR of ... wait for it... 0.3% www.nejm.org/doi/full/10.1056/NEJMoa2026116?query=featured_homeThis is, of course, the figure Ionannidis has been viciously attacked for suggesting all those months ago. We should acknowledge that there is no one "true" IFR for the virus - it depends very much on age structure and general health of the population the virus infects. It will be higher in older unhealthy populations (the West) and lower in younger populations (developing world, current "second wave"). We should also beware of the tendency towards ad hominum attacks on people whose work doesn't agree with pre-formed views or beliefs. EDIT: also of note is that immunity did not drop off over the 4 months of the study (and in fact increased initially) What's your view about Pillar 1 testing and hospitalisation? Clearly, confirmed cases from Pillar 1 have dropped significantly since Early April and the number of people in hospitalisation keeps falling. Would you say if Pillar 1 cases go up, we will start seeing the second wave? Cumulative Median Age of Pillar 1 patients is 62 years old compared to pillar 2 patients (42) assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/912961/COVID19_Weekly_Report_26_August.pdf
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IFISAcava
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Post by IFISAcava on Sept 2, 2020 13:22:22 GMT
Data from careful study in Iceland gives an IFR of ... wait for it... 0.3% This is, of course, the figure Ionannidis has been viciously attacked for suggesting all those months ago. We should acknowledge that there is no one "true" IFR for the virus - it depends very much on age structure and general health of the population the virus infects. It will be higher in older unhealthy populations (the West) and lower in younger populations (developing world, current "second wave"). We should also beware of the tendency towards ad hominum attacks on people whose work doesn't agree with pre-formed views or beliefs. EDIT: also of note is that immunity did not drop off over the 4 months of the study (and in fact increased initially) What's your view about Pillar 1 testing and hospitalisation? Clearly, confirmed cases from Pillar 1 have dropped significantly since Early April and the number of people in hospitalisation keeps falling. Would you say if Pillar 1 cases go up, we will start seeing the second wave? Cumulative Median Age of Pillar 1 patients is 62 years old compared to pillar 2 patients (42) It's all a bit chicken and egg What strikes me is that cases are now in younger people (median age well down in both pillar 1 and 2) so deaths and hospitalisations will be down (a lot) for that reason alone, whatever else is going on in terms of number of cases in the wild. But the problem is that because we are testing so many more, it isn't clear to what extent there are actually more cases (and as overall estimated R has been at or around 1 for a long time, you wouldn't expect much growth in number of cases - albeit that local outbreaks will be hidden in that R figure, that R is only approximate and based on assumptions, and that even small increases over 1 will eventually lead to more cases exponentially). So - dunno is the answer.
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Post by Ton ⓉⓞⓃ on Sept 2, 2020 18:34:38 GMT
I was in my car on the A40 going into London at about 6.40am I was really struck by how much busier the road was than it has been since, say, Lockdown ended. It just gives me the feeling that if as a country we're bouncing along at R~1 then in a month or so it's re-emergence time for London unless measure are taken of course.
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slippery
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Post by slippery on Sept 2, 2020 19:50:46 GMT
Am in a C19 free area so we haven't needed facemasks, but are going on a flight so need "medical grade" masks for the journey. Purchased online, thinking I was getting ones with a reduced chance of misting up specs: "The Layers stretch and allow your skin and vapours to wick away increasing comfort. High airflow, whilst blocking droplets through the mask to reduce feelings of not being able to breath. The elasticity for comfort and fit is built into the patented material" etc. But as soon as my partner tried his on he misted up. Apart from the general online advice about sticking it on his nose with surgical tape or having his specs halfway down his nose etc, has anyone found a design that is easier for spec wearers to avoid misting up? Don't really want to waste another £25. Quite entertained that some of the descriptions include "breathable"! Was kinda hoping they would ALL be breathable
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benaj
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Post by benaj on Sept 2, 2020 21:06:25 GMT
Am in a C19 free area so we haven't needed facemasks, but are going on a flight so need "medical grade" masks for the journey. Purchased online, thinking I was getting ones with a reduced chance of misting up specs: "The Layers stretch and allow your skin and vapours to wick away increasing comfort. High airflow, whilst blocking droplets through the mask to reduce feelings of not being able to breath. The elasticity for comfort and fit is built into the patented material" etc. But as soon as my partner tried his on he misted up. Apart from the general online advice about sticking it on his nose with surgical tape or having his specs halfway down his nose etc, has anyone found a design that is easier for spec wearers to avoid misting up? Don't really want to waste another £25. Quite entertained that some of the descriptions include "breathable"! Was kinda hoping they would ALL be breathable £25??? You can get better value elsewhere for OEKO-TEX® Standard 100 certified Fabric Masks. You won't see any medical staffs using these at hospitals or surgery. Definitely not medical grade like ASTM-2100 /N95
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Post by bernythedolt on Sept 3, 2020 0:51:56 GMT
Data from careful study in Iceland gives an IFR of ... wait for it... 0.3% www.nejm.org/doi/full/10.1056/NEJMoa2026116?query=featured_homeThis is, of course, the figure Ionannidis has been viciously attacked for suggesting all those months ago. We should acknowledge that there is no one "true" IFR for the virus - it depends very much on age structure and general health of the population the virus infects. It will be higher in older unhealthy populations (the West) and lower in younger populations (developing world, current "second wave"). We should also beware of the tendency towards ad hominum attacks on people whose work doesn't agree with pre-formed views or beliefs. EDIT: also of note is that immunity did not drop off over the 4 months of the study (and in fact increased initially) Iceland is a rather special case, being an island largely isolated from the real world. They've endured 29 deaths per million population while the attrition rate in many European nations has been a massive 20-fold higher. Iceland's supposed IFR of 0.3% is most likely a special case, and not representative of the world at large: Johns Hopkins University - select the fourth tab (CFR) beneath the map and click on the individual white dots - gives Iceland a nice low CFR of 0.47%, but large swathes of Europe as 5% to 15% - 10 to 30 times higher. Ditto the US and South America. So for every Iceland at one extreme (0.47%), there is a Mexico at the other extreme (18%). Regarding any attacks on the work of Ioannidis, he hasn't exactly covered himself in glory. He wrote up in March this year, "If we assume that case fatality rate among individuals infected by SARS-CoV-2 is 0.3% in the general population — a mid-range guess from my Diamond Princess analysis — and that 1% of the U.S. population gets infected (about 3.3 million people), this would translate to about 10,000 deaths". If he goes on record like that, he might expect some brickbats! Policymakers are relying on accurate predictions from their scientists and statisticians, not fairy-tales. Indeed his assumption of 3.3m infections resulting in 10k deaths can now be back-tested. The US has almost double those infections (6.3m cases, Worldometers), so listening to Ioannidis we might expect almost 20,000 deaths by now. I wonder how he explains 190,000 deaths and counting? Could his estimate of 0.3% be too low, by a whole order of magnitude? Johns Hopkins certainly thinks so, studying their map.
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IFISAcava
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Post by IFISAcava on Sept 3, 2020 7:43:45 GMT
Data from careful study in Iceland gives an IFR of ... wait for it... 0.3% www.nejm.org/doi/full/10.1056/NEJMoa2026116?query=featured_homeThis is, of course, the figure Ionannidis has been viciously attacked for suggesting all those months ago. We should acknowledge that there is no one "true" IFR for the virus - it depends very much on age structure and general health of the population the virus infects. It will be higher in older unhealthy populations (the West) and lower in younger populations (developing world, current "second wave"). We should also beware of the tendency towards ad hominum attacks on people whose work doesn't agree with pre-formed views or beliefs. EDIT: also of note is that immunity did not drop off over the 4 months of the study (and in fact increased initially) Iceland is a rather special case, being an island largely isolated from the real world. They've endured 29 deaths per million population while the attrition rate in many European nations has been a massive 20-fold higher. Iceland's supposed IFR of 0.3% is most likely a special case, and not representative of the world at large: Johns Hopkins University - select the fourth tab (CFR) beneath the map and click on the individual white dots - gives Iceland a nice low CFR of 0.47%, but large swathes of Europe as 5% to 15% - 10 to 30 times higher. Ditto the US and South America. So for every Iceland at one extreme (0.47%), there is a Mexico at the other extreme (18%). Regarding any attacks on the work of Ioannidis, he hasn't exactly covered himself in glory. He wrote up in March this year, "If we assume that case fatality rate among individuals infected by SARS-CoV-2 is 0.3% in the general population — a mid-range guess from my Diamond Princess analysis — and that 1% of the U.S. population gets infected (about 3.3 million people), this would translate to about 10,000 deaths". If he goes on record like that, he might expect some brickbats! Policymakers are relying on accurate predictions from their scientists and statisticians, not fairy-tales. Indeed his assumption of 3.3m infections resulting in 10k deaths can now be back-tested. The US has almost double those infections (6.3m cases, Worldometers), so listening to Ioannidis we might expect almost 20,000 deaths by now. I wonder how he explains 190,000 deaths and counting? Could his estimate of 0.3% be too low, by a whole order of magnitude? Johns Hopkins certainly thinks so, studying their map. Thanks Bernie I am not defending his views, I am defending his expertise and right to express views without the vitriol he received. That's how science and understanding progresses. He didn't predict 1% would be infected, that was just a scenario. The US obviously has much higher rates (as does most of the world - it soon became pretty clear to everyone that more than 1% would be infected globally). I don't think the IFR estimates are too far out, and definitely nowhere near an order of magnitude, it's just the % of population infected is high. But also the US has other factors increasing the IFR and death rates - high rates of medical illnesses, high obesity, older population, unjoined up elderly care and poor health care for many. So if it is 0.3% in Iceland, it will likely be higher than 0.3% in the US as a whole. As I said, there is no one "true" IFR. The issue for me is that it is difficult to have any sort of rational debate as it rapidly becomes emotional, polarised and politicised. Sure, people are afraid and angry, but we all know that the best decisions are not made when in those states of mind.
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Post by bernythedolt on Sept 3, 2020 11:39:02 GMT
Iceland is a rather special case, being an island largely isolated from the real world. They've endured 29 deaths per million population while the attrition rate in many European nations has been a massive 20-fold higher. Iceland's supposed IFR of 0.3% is most likely a special case, and not representative of the world at large: Johns Hopkins University - select the fourth tab (CFR) beneath the map and click on the individual white dots - gives Iceland a nice low CFR of 0.47%, but large swathes of Europe as 5% to 15% - 10 to 30 times higher. Ditto the US and South America. So for every Iceland at one extreme (0.47%), there is a Mexico at the other extreme (18%). Regarding any attacks on the work of Ioannidis, he hasn't exactly covered himself in glory. He wrote up in March this year, "If we assume that case fatality rate among individuals infected by SARS-CoV-2 is 0.3% in the general population — a mid-range guess from my Diamond Princess analysis — and that 1% of the U.S. population gets infected (about 3.3 million people), this would translate to about 10,000 deaths". If he goes on record like that, he might expect some brickbats! Policymakers are relying on accurate predictions from their scientists and statisticians, not fairy-tales. Indeed his assumption of 3.3m infections resulting in 10k deaths can now be back-tested. The US has almost double those infections (6.3m cases, Worldometers), so listening to Ioannidis we might expect almost 20,000 deaths by now. I wonder how he explains 190,000 deaths and counting? Could his estimate of 0.3% be too low, by a whole order of magnitude? Johns Hopkins certainly thinks so, studying their map. Thanks Bernie I am not defending his views, I am defending his expertise and right to express views without the vitriol he received. That's how science and understanding progresses. He didn't predict 1% would be infected, that was just a scenario. The US obviously has much higher rates (as does most of the world - it soon became pretty clear to everyone that more than 1% would be infected globally). I don't think the IFR estimates are too far out, and definitely nowhere near an order of magnitude, it's just the % of population infected is high. But also the US has other factors increasing the IFR and death rates - high rates of medical illnesses, high obesity, older population, unjoined up elderly care and poor health care for many. So if it is 0.3% in Iceland, it will likely be higher than 0.3% in the US as a whole. As I said, there is no one "true" IFR. The issue for me is that it is difficult to have any sort of rational debate as it rapidly becomes emotional, polarised and politicised. Sure, people are afraid and angry, but we all know that the best decisions are not made when in those states of mind. Yes, but a scenario to which he explicitly ascribed ~10,000 US deaths should it arise. So their actual 2% infection rate should - according to him - have led to about 20,000 deaths, rather than the 190,000 they've suffered. The figures did not support his iffy analysis back in March (as I said on this forum at the time) and they don't support him today. While I agree he has the right to express his views, a statistician of his calibre and stature ought to be apologising to his country for misleading them so. Remember that his March paper went on to describe how SARS2 should have warranted no more media attention than a second rate ball game...
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