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Test results are not binary. Good tests are not all the same

Simon Gibbs of Libertarian Home renown has some interesting information about Wuhan Coronavirus testing.

By the end of this article, I want you to be writing to someone and sharing this link. That person could be your MP, your employer, or if you are in a position of power, someone in your organisation who you will want to start making a plan. Preferably, all three.

There is a lot of drama in comment sections and on the street about false positives and tests for The Coronavirus producing positive results for other coronaviruses, like the common cold. Usually this is understood to mean you should ignore the Government. I have some sympathy for that, obviously, but what I have come to understand about tests, however, is that they are not binary. They are not limited to producing yes and no answers – if the person using them allows for it.
Usually the people doing tests don’t allow it, for reasons that are basically economical, but actually the missing subtlety is interesting. Tests can tell you how much virus is present – the “viral load”.

There are two other interesting properties of tests:

Specificity – a test with good specificity only detects SARS-COVID-2 i.e The Coronavirus, and not older or similar bugs

Sensitivity – a test with good sensitivity will tell you if your body has ever come into contact with SARS-COVID-2 even if the “viral load” is small.

There were, apparently, some issues with specificity at one point. The major issue at the moment is that most tests are far too sensitive.

If you just caught the virus yesterday then you are probably not spreading it yet, but you’ll test “positive” because there are already a few thousand bits of virus DNA in the sample. If you had it in January then you will have stopped spreading at the very latest by mid-February but would still be testing “positive” in March, because there are still thousands of bits of virus DNA in the sample. Either of these results makes it unclear what you, as an individual, should do about it.

What researchers have learned is that SARS-COVID-2, specifically, is mainly transmissible in a period between 1 to 6 days when your body is producing trillions of copies of the virus. If the test was able to tell you that you had trillions of copies in your body, then you would know what to do. You would know that tomorrow will be a bad day for you, and that going to a party today would make next Saturday a bad day for everyone at the party.

The brevity of this period is easy to overstate. It might be up to six days long, but by day two of that period you will probably want to be in bed anyway, and limited transmission will actually happen after that.

Testing as a means to stop transmission has only one day to do anything useful.

Now the real kicker with tests is that they are sometimes taking two days to come back. By the time you get the result, nearly all the transmission that might have happened has happened. It is too late to close the stable door, the epidemiological horse has well and truly bolted. Your mates at the party are sick. Hopefully you will be able to apologise to them.

This does not mean we have bad tests. We have great tests. The problem is that they are diagnostic tests, not screening tests. They are designed for working out why people are ill, not as a tool for stopping them from being ill.

Enter Michael Mina (the virologist, not the chef). He has been making the news a bit, but only once in the UK and the Daily Mail did not do this justice. This is a shame because his ideas (of which the above is a summary) are very exciting.
He wants to make cheap, rubbish tests.

Michael Mina’s tests will be so bad, they will miss something like a third of infections. This is not a problem, because they will be so cheap you can do them 3-7 times a week and by the time you are infectious and your body is swamped with virus DNA there is no way that even a cheap rubbish test will miss it.

Apparently it is a bit easier to make tests that work fast if they are allowed to be insensitive to a third of cases. Michael Mina wants his to be done in your home and to work while you eat your breakfast.

As an individual you could buy boxes of $1 tests and test yourself daily, if you become a threat to your colleagues you will know about it before you leave for work.

As an employer you could send boxes of $1 tests to your employees and require them to show the result before entering the office. You can now reopen your office.

As a University Dean you could require students to present a clear $1 test result before entering the campus. You can now reopen your campus.

As a government, you can repeal your Coronavirus legislation (up for renewal in September, I hear), and get on with delivering the will of the people, rather than flailing about trying to bend the people to your will.

Unfortunately we live in a world in which every aspect of the medical industry is affected by the need to seek Government approval for new products – tests included. Making cheap rubbish fast tests is not easy to do if the regulator doesn’t understand that these are cheap screening tests and low sensitivity is fine.

So please share that website with your MP and tell them they have a new job to do – to get a test like this approved.

Share the website with your employer or University so that they can start to get their head around the notion that they need to set up a medical screening program – something that I imagine is new for them.

If you are in a position of power, start drawing up options so you can reap the benefits.

If you are not persuaded, I suggest you spend 30 minutes watching Michael Mina persuade a panel of virologists. If you are anything like me, you’ll watch to the end.

23 comments to Test results are not binary. Good tests are not all the same

  • John B

    Haystack; needles… stop looking.

  • APL

    CDC

    “Table 3 shows the types of health conditions and contributing causes mentioned in conjunction with deaths involving coronavirus disease 2019 (COVID-19). For 6% of the deaths, COVID-19 was the only cause mentioned.”

    Or, 94% of people died from other conditions, but caught COVID-19 during the course of their demise.

  • Fred Z

    The government was full of lying shit, almost certainly knew it was lying shit, but used that lying shit to go power mad crazy?

    No news there, same, same, since forever.

  • suburbanbanshee

    If somebody already had the virus back in, say, December, would tests still show antibodies, etc?

    A lot of people around here already had it, by the symptoms, but they are afraid to get tested if it would show up, because that would cause a lot of disruption, continued growth of “cases” in the statistics, possible closings of businesses again, etc.

    I have a feeling that most people already got it right before and after Christmas, because that was when “mysterious not a flu with three weeks of dry coughs” was going around, and that’s why the official numbers around here were so low until testing increased.

  • Natalie Solent (Essex)

    Simon Gibbs writes,

    Unfortunately we live in a world in which every aspect of the medical industry is affected by the need to seek Government approval for new products – tests included. Making cheap rubbish fast tests is not easy to do if the regulator doesn’t understand that these are cheap screening tests and low sensitivity is fine.

    Thank you for a very rational post that avoids the extremes of paranoia about Covid-19 and paranoia about government. While scepticism about the performance of government is warranted for exactly the reasons of bad incentives that you state, that does not mean that its performance cannot be made better or worse. Persuasion is worth trying.

  • @suburbanbanshee I understand the details less well than I would like, but my understanding is you would probably have antibodies (which is a good thing, because you adapted) and probably be negative for copies of the virus in your nose and throat (also a good thing). Tests can also test for different things. There are the antibody tests that you mention, and there are tests (including the extremely sensitive PCR test) which test for the virus itself.

    So you can categorise tests by what is tested, speed, cost, method of taking the sample (spit, or swab), sensitivity and specificity, as well as the mechanisms involved. So there are a lot of different ways to separate one test from another.

    I take your point about tests justifying a further disruption, which is one reason the Government should stay out of it. You’ll notice I advocate for screening at offices and campuses, but not national screening. This is a good case of technology enabling a libertarian solution, if politicians and regulators can be persuaded to step away.

    Tactically, if you feel you are likely to be negative, taking a Government test makes you part of the evidence that it’s all fine out there.

  • Nullius in Verba

    “If somebody already had the virus back in, say, December, would tests still show antibodies, etc?”

    It would show up in antibody tests, (we think,) but not in the sort of tests they’re talking about here. Antibodies only show up after you’re recovering from the disease.

    “A lot of people around here already had it, by the symptoms, but they are afraid to get tested if it would show up, because that would cause a lot of disruption, continued growth of “cases” in the statistics, possible closings of businesses again, etc.”

    An antibody test shouldn’t cause disruption. If you have already had it, got over it, and have antibodies, then you’re probably not infectious and have no need to self-isolate. We’re not sure yet if having had it before gives immunity (although it’s expected), but it’s only those currently infected and infectious we’re disrupting.

    The antigen/virus tests being discussed here possibly would result in disruption. If you got infected, you would have to self-isolate. But it’s less likely to cause you disruption than the track-and-trace, since you are only going to isolate if you’re really infected, not just if it’s suspected.

    “I have a feeling that most people already got it right before and after Christmas, because that was when “mysterious not a flu with three weeks of dry coughs” was going around, and that’s why the official numbers around here were so low until testing increased.”

    Lots of diseases cause coughs.

    The best indicator of when the epidemic started is when the number of covid-19 deaths started ramping up, and the rate at which it does so. Roughly 1% of people who catch it die. So if the death rate is going up 10-fold per week, it would take two weeks for the number of cases to multiply a hundredfold to the point where some people start to die instead of recover, and a few more weeks before that to allow for the time between infection and death. Basically, the epidemic would have started around 4-6 weeks before the first death; a little longer if the rate of rise is slower. There may have been a very small number of cases circulating before that, but the fraction of the population infected is so tiny that “most people” would not have got it, nor heard about it.

    Even now, less than 10% of the population have ever had the disease according to antibody tests, in many places it’s still around 5%. Back in December it would have been more like one in a million.

    “Thank you for a very rational post that avoids the extremes of paranoia about Covid-19 and paranoia about government.”

    Agreed. It’s a good post, and the proposal seems very sensible to me.

  • APL

    NiV: “The best indicator of when the epidemic started is when the number of covid-19 deaths started ramping up, “

    That was when the Marxists in the BBC were ramping up the UK COVID-19 hysteria. And wen the Marxists on SAGE were gulling the gullible in government.

    There are enough indications – samples from sewage ( COVID-19 virus is shed in faeces ) – that it was well established in the European population in November – December.

    And if as we think, COVID-19 did originate in China, pretty much all of Europe had been exposed to the virus as Europe was (1) a popular tourist destination for Chinese tourists.
    (2) Every University city in Europe and the UK had young students from China, the very demographic that can contract COVID-19 but exhibit no symptoms.

  • Nullius in Verba

    “There are enough indications – samples from sewage ( COVID-19 virus is shed in faeces ) – that it was well established in the European population in November – December.”

    So maybe it didn’t come from China after all? Maybe it started in Europe, and spread to China?

  • APL

    NiV: “So maybe it didn’t come from China after all? Maybe it started in Europe, and spread to China?”

    Who actually gives a flying fuck?

    Seasonal flu is, seasonal flu, it comes around every year.

    The thing we should be concerned about is a few strategically placed saboteurs managed to destroy 20% of the economy in just three months.

    As I posted above, the CDC reports only 5% of those who died with COVID-19 had no other condition.

    Which echoes the report by the Italian authorities at the height of the mania (23rd March).

    “The age of our patients in hospitals is substantially older – the median is 67, while in China it was 46,” –Prof Ricciardi

    Seems to me that means more Italians would be susceptible to COVID-19 simply by virtue of their age, plus being old, are likely to have other contributing conditions.

  • Paul Marks

    Damn – I pressed the wrong key, and everything I had typed vanished.

    “My bad” as the young say – but I am not typing all that again.

    Anyway, turning from what I have already typed (but lost), I have just seen the last comment by Nullius – and it shows the level of extreme dishonesty I have come to expect to this person.

  • Paul Marks

    I will try a recap, about the China Virus Covid 19 – released (by accident – or on purpose) from the research centre near the city of Wuhan.

    Mass testing – pointless unless you want mass hysteria and panic, which is why President Obama was against mass testing (indeed stopped it) during the last epidemic, and supports it now.

    Testing when someone has the very first signs of the virus may be useful – but at doses that medical doctors will prescribe it (NOT overdoses) the treatment of hydrozychlooquine, zinc sulphate and azthroomycin, will do no harm even if someone is not infected by Covid 19. Even with early treatment death is still possible – but the chances of death (already LOW) are greatly reduced with early treatment.

    The international establishment (government, corporate, NGO) has not made any secret of the fact that it has been, FOR YEARS, hoping for a massive pandemic to use as an excuse for a totalitarian agenda – the documents for the Great Reset, Agenda 21, Agenda 2030, “sustainable development”, “build back better” are in the public domain.

    This does NOT prove the international elite created the virus on purpose, or that they released it on purpose – but they were certainly eager to exploit these events for their totalitarian agenda.

    To be useful the virus would have to kill very large numbers of people.

    To some extent this can be achieved without actually killing people – by the process of exaggerating death figures. Thousands of “Covid 19 victims” have NOT come back to life in England (this is not the Zombie Apocalypse), they did not die of Covid 19 in the first place. The idea was to promote fear in order to generate submission – and it was not a British idea, it was international.

    The former Prime Minister of Ireland essentially admitted this – and he was not punished in any way for exaggerating death figures. Indeed he is Deputy Prime Minister in the “new” government of the Republic of Ireland.

    However, large numbers of real deaths were needed – hence such things as various State and national governments ORDERING care homes to accept infected people in order to spread the virus to people especially vulnerable to it.

    In some places this may have been an accident – but what happened in New York looks very much like it was deliberate (to push up the body count). This seems to have been the case in the Republic of Ireland as well – again no one has been punished. Who would punish them? They are the system Who is the Custodian of the Custodians?

    You are not going to get justice in the legal system of say New York – the D.A. is a Progressive, so is the Judge. How are you going to get justice? And it is the same in many other States.

    A Progressive starts with the assumption that whatever legal result benefits the Progressive cause is the correct result – with traditional concepts of justice being reactionary absurdities.

    As for the systematic smearing and discouraging of early treatment for Covid 19 – well that has been going on since March.

    After almost six months it is very hard to believe that this was not a deliberate campaign by the establishment.

    Their totalitarian agenda would only be accepted if there was mass death – so there had to be mass death.

    It should be stressed that these people, the establishment elite,do not regard themselves as evil.

    According to utilitarian ethics – some bad things (lying, killing and so on) IF (providing) they lead to a greater good – defined in terms of happiness (the greatest good of the greatest number).

    If “sustainable development” (or whatever totalitarianism is to be called) is a vastly better society than “capitalism” (free competition and private property rights) then, according to this point of view, sacrifices (whilst very unfortunate indeed).

    This is PRE Marxist – it goes back to Saint-Simon and others. Big Business (including Credit Bubble bankers) is NOT to be shot – on the contrary, they are to have a vital role in the new society (without messy competition and pesky consumer demands).

    The most fair course of action would be for people to read such things as Agenda 2030 for themselves.

    These documents are in the public domain – and you (reader) may be attracted to this vision.

    It may well come to pass – after all the United States of America is just about the only thing that stands against this vision becoming world reality – People’s Republic of China Social Credit system and all.

    And they may soon change – with the coming election.

    Remember the American establishment (including most of Big Business) is committed to a planned society – and despises the “reactionary” Constitution of the United States.

    They would point out they are very much in tune with international educated opinion – including on the matter of acceptable casualties to achieve the Greater Good.

  • Bell Curve

    Paul. WTF has ANY of that rambling digression got to do with the article? 😆

  • Nico Metten

    Why are we still talking about how we can stop the spread. Epidemics end when herd immunity is reached not sooner, not later. So we need to spread it as quickly as possible to get there. The quicker the better. But this is all old news. The epidemic is over. The UK is at herd immunity.

    BTW. tests are of course less accurate the fewer people have the virus. Let us say no one has the virus, then every positive test is a false positive test. Let us say 50% of people have the virus. then, assuming that we have a good test, most positive tests are actually detecting the virus. That is something important to understand.

  • Nullius in Verba

    “As I posted above, the CDC reports only 5% of those who died with COVID-19 had no other condition.”

    Oh, you mean where you said: “Or, 94% of people died from other conditions, but caught COVID-19 during the course of their demise.”?

    If the death certificate mentions causes A and B and C, why is it not the case that there is no cause of death? Because having said that A wasn’t the cause of death because of the presence of B and C, you can equally well say B was not the cause of death because of the presence of A and C, and likewise about C because of A and B. They didn’t die of anything.

    Or does it means that if you have conditions B and C, it’s not possible to die of A? Having B and C somehow stops A from killing you? The same can then be said for B, aand for C too. So it’s not possible to die of anything. Strange.

    Of course, that leaves us the mystery of how to explain the massive spike in the total number of deaths that came along just as the Covid-19 epidemic was happening. (Figure 34 here.) All those other background health conditions, that did nothing spectacularly different year after year, suddenly this year started killing people at double the usual rate, coincidentally just at the moment they were catching Covid? What happened to make those other conditions suddenly so much more deadly?

    “Why are we still talking about how we can stop the spread. Epidemics end when herd immunity is reached [] sooner, not later.”

    Because they realised that would result in about half a million deaths in the UK, and two million deaths in the US, minimum. The disease kills about 1% of those it infects (if the hospitals are not overwhelmed so everyone can get treatment). So in the UK it has infected about 7% of the population – 4.7 million people – and killed about 1% of them – 45,000 people. It needs to infect about 60-80% of the population to achieve herd immunity, about 10 times as many, which would cause about ten times as many deaths.

    If the epidemic was allowed to happen unrestrained, it would spread so fast and so many people would get sick at once that most people would be unable to get hospital treatment. In that case the death rate would multiply from 1% to something like 2-5%. So double the totals.

    No modern Western politician wants to go down in the history books as having caused millions of deaths. That’s about twice the number as died in the UK or US as a result of the five years of World War II, crammed into a few months. No modern Western electorate would tolerate it, either. It’s a political choice.

    “BTW. tests are of course less accurate the fewer people have the virus. Let us say no one has the virus, then every positive test is a false positive test.”

    They normally use two numbers to measure accuracy, for that very reason. Sensitivity counts the fraction of people with the condition that the test correctly identifies as having it. Specificity counts the fraction of people who don’t have the condition that the test correctly identifies as not having it. If nobody has it, Sensitivity gives an indeterminate 0/0 error, and specificity works as normal.

    If TP, TN, FP, and FN are true positives, true negatives, false positives, and false negatives, then Sensitivity is TP/(TP+FN) and specificity is TN/(TN+FP). If nobody has it, then TP = FN = 0, and TN and FP are generally non-zero. But except in this extreme case, both measures estimate fixed numbers, irrespective of how many people actually have it.

  • CaptDMO

    From the US..
    Chinese Wuhan Novel Coronavirus-19.
    “Oh, well we call that SARS Covid-2 now”
    Well, I don’t.
    And I practice extreme discrimination in my “experts”. You can just keep nattering among your “research” selves.
    Let me know when the “woulda’, coulda’, shoulda’, [without evidence], mask on/mask off, “No! That’s POISON!” flatten the curve, send the Uni students home, crap is over….. so I can get back to ignoring the champions of Anthropogenic Global Warming, Free college, Open borders, and “See what you MADE me do!” AntiFa/BLM/BDS/ACAB/ Progressive Socialist, mostly peaceful protests.

  • Clovis Sangrail

    @NiV

    But except in this extreme case, both measures estimate fixed numbers, irrespective of how many people actually have it.

    What does that mean?
    The proportion of people who actually have it is highly influential on the proportion of false positives (and false negatives). To take your figure that 7% have had it and let’s say double it, to be hypothetical, then with a false negative error probability of 10% and a false positive 20%, in a 100,000 tested, 14,000 would actually have it (or antibodies to it), of which we’d pick up 12,600 and 86,000 would not, of which we’d report 17,200 as having it. So we’d estimate a prevalence of 29.8% not 14%. Over 57% of those testing positive would actually be negative.

    It would show up in antibody tests, (we think,)

    Not true. Estimates range from 50% and up as to the proportion of those whose immune system has killed it off using T-cells – thus leaving them with no antibodies even though they have recovered from it.

    The disease kills about 1% of those it infects

    We REALLY don’t know that. It’s more like the “case fatality rate” is that and we are very clear that a significant proportion of cases are so mild that we don’t spot them so the denominator is still much too low.

    And what is the alternative to herd immunity? A vaccine? When it’s an RNA based virus which mutates extremely fast? 40 odd strains already identified? Maybe. Maybe the other effects (non-medical) will kill us all too.

  • Paul Marks

    On the positive side…..

    Sweden and many other places appear to have achieved herd immunity. In some cases, such as Sweden, this was a deliberate policy – in other cases it has happened by accident, after an orgy of deaths in New York and New Jersey the death number appears to have been stuck for weeks now. As “Tony Heller” puts it – the virus is having a hard time finding vulnerable people to kill in New York, because it has already killed them.

    It the intention of the “lockdown” in such places as New York, New Jersey and so on was to reduce deaths it was a farcical failure (as these places had the highest death rates on the planet) – but if the intention of the “lockdowns” was to INCREASE deaths, then the policy was a success but a self limiting one. Once you have killed people it is difficult to kill the same people again.

    There are claims around the world of “reinfections” from various parts of the world – but, as far as I know, not even the establishment elite (with their dreams of “Technocracy” totalitarianism) has claimed that anyone has died from one of these “reinfections”.

    Unless the establishment elite “tweek” the virus in order to make it more effective (and some people have suggested that a natural virus was “tweeked” in the Wuhan research establishment) or a NEW virus is introduced (watch the film of Mr and Mrs Gates as they smile and gloat over the possibility of a NEW virus – if Covid 19 does not give them sufficient help in achieving their totalitarian goals), Covid 19 is essentially no longer a threat in parts of the world.

    The totalitarian plans will continue (including the “mail in ballot” VOTE RIGGING in the United States – in order to destroy democracy and allow the establishment elite to decide who wins elections regardless of how ordinary people vote) – because these plans were drawn up long BEFORE Covid 19, which is just being used as an EXCUSE for the long standing totalitarian plans.

    How much of all this does an elected politician, such as Prime Minister Johnson, know?

    At this stage does it matter how much they know?

    Whether they ordered such things as the “lockdown” out of malice or because they were deceived by totalitarian “experts” and “public servants”, the result is the same.

    Such polices as the “lockdowns” have nothing to do with public health – they were thought out (by “experts” and the rest of the establishment elite) long before anyone had even heard of Covid 19 – the purpose of the policies is to undermine both the economy and civil liberties, in order to pave the way for the totalitarian great “Reset” – or “sustainable development” or “build back better” or whatever you want to call the project of tyranny – of total control (totalitarianism).

    Such policies were thought out long before Covid 19 – see the documents (in the public domain) around Agenda 21 and Agenda 2030.

    Mass testing is for purpose of promoting mass panic and fear – leading to mass SUBMISSION.

  • Nullius in Verba

    “What does that mean? The proportion of people who actually have it is highly influential on the proportion of false positives (and false negatives).”

    Which is why we don’t use false positives and false negatives to measure the accuracy of a test, we instead use sensitivity and specificity.

    What it means is that the expectation values for the ratios are constant, and don’t vary with the number of cases.

    “Not true. Estimates range from 50% and up as to the proportion of those whose immune system has killed it off using T-cells – thus leaving them with no antibodies even though they have recovered from it.”

    That’s not something I’ve seen. Do you have a reference? How was the estimate calculated?

    Having just looked around for whatever it was you was talking about, I’ve found some research from the Karolinska Institute indicating that previous non-lethal coronaviruses may have created T-cells against generic bits of coronavirus protein, and are able to recognise and attack SARS-CoV-2, but I didn’t see any indication that they’d shown that gave definitive immunity to SARS-CoV-2. (The immune system definitely reacts to the proteins, but is it enough to stop the SARS-CoV-2 infection?) The antibodies are not long-lasting, so if they got the T-cells from a coronavirus cold ten years ago, the antibodies they generated at the time would have faded. And since T-cells are one of the later stages in the immune response that usually kicks in only after the antibodies have failed to stop it, I’d be surprised if there was a way T-cells could kill it without antibodies forming unless the person is immunosuppressed and doesn’t form antibodies to anything. Antibodies latch on to the virus and target it for destruction before it gets into the cell. T-cells locate infected, dying cells and destroy them.

    I also found this research measuring T-cell responses in a small sample of the population. I’m still working my way through it – it’s a lot more technical than the other paper – but it does observe some people who come up negative on antibody tests for SARS-CoV-2 but with a positive T-cell response. (“Further analysis revealed that SARS-CoV-2-specific CD4+ and CD8+ T cell responses were present in seronegative individuals, albeit at lower frequencies compared with seropositive individuals (Figure 4F).”) They also say “It remains to be determined if a robust memory T cell responsein the absence of detectable circulating antibodies can protect against SARS-CoV-2.” If it does, then that suggests that the other ‘common cold’ coronaviruses could be used as a vaccine, like cowpox was for smallpox.

    Is that the research you mean? Or is there something else I’ve not found yet? Either way – thanks! I found out something new because of your comment.

    “We REALLY don’t know that. It’s more like the “case fatality rate” is that and we are very clear that a significant proportion of cases are so mild that we don’t spot them so the denominator is still much too low.”

    That’s based on the infections detected by antibody tests, so includes cases where the symptoms are mild or non-existent. It might not include cases where people don’t produce antibodies, if there are any.

    “And what is the alternative to herd immunity? A vaccine? When it’s an RNA based virus which mutates extremely fast? 40 odd strains already identified?”

    There are mutations, but most of them are in parts of the genome that don’t affect the function.

    If it can mutate fast enough to evade a vaccine, then catching it once wouldn’t give immunity to catching it again. So herd immunity wouldn’t work either.

    Vaccines are basically a way to create artificial herd immunity

    “Sweden and many other places appear to have achieved herd immunity.”

    Nope. They’re still applying restrictions. It’s just that the population there are sensible and did it voluntarily and earlier, rather than having to be forced to do it by the government after it was nearly too late. I think their nationally-averaged infection level is still at or below 10% too.

    If you’re at R = 1 herd immunity levels without restrictions, then the numbers would drop really fast and R would be much less than 1 with restrictions. If we had herd immunity so we didn’t need restrictions, then the precautions we’re taking ought to wipe the epidemic out within a couple of weeks. And it hasn’t. We’re still getting flare-ups and a continual stream of new cases.

    We’ve got the brake pedal pressed down hard, and we’re *still* moving. What do you expect to happen if we take our foot off the brake?

  • […] (h/t: masgramondou) A guest poster at long-standing Libertarian group blog Samizdata discusses COVID19 tests, why they are not all equal, and how rapid and inexpensive reagent paper […]

  • Because they realised that would result in about half a million deaths in the UK, and two million deaths in the US, minimum. (Nullius in Verba, September 1, 2020 at 10:01 pm)

    ‘realised’ 🙂

    Back in March, the UK government were going for herd immunity when Neil my-rules-are-for-thee-not-me Ferguson told them, based on his decades of experience of over-predicting pandemics, and his team’s wretched-quality code, that terrible things would happen unless they changed course. We don’t know from our own experience what would have happened – and nor, you claim, can we know from Sweden, whose history you so amusingly interpret in your next comment:

    They’re still applying restrictions. It’s just that the population there are sensible and did it voluntarily and earlier, rather than having to be forced to do it by the government after it was nearly too late.

    An interesting view of what others here see as the extremely compliant, even docile, UK population. 🙂

    I can see that your interpretation of Sweden may be necessary to your maintaining your interpretation of the UK. Readers can form their own view of the accuracy of either.

    I would of course agree that just because 94% of those who had the ChiComCold and later died also had other things does not mean the virus never had anything to do with it. George Floyd had the virus and later died – but so too did some who might be alive if they had not caught it. Hopefully the UK’s data will improve as it is reviewed for these issues. One thing seems likely – it will improve to push totals downwards.