The most impressive aspects of the UK's Pandemic Response

[zico]

I see, so your objection to "mass population infection testing" is to quote a report that is on test, trace and isolate that highlights the large gaps are as a result of "gaps in symptom recognition" (by people), and "willingness to test" (by people).

Presumably you are actually agreeing then that the "mass population infection testing" is good, but is made ineffective, by the population? You're probably right it could be better if say 2 million tests a day were carried out rather than half of that. But even still by international comparisons I think the UK is relatively doing well on this score.

If our current testing is made ineffective by the population, we can either
a) blame the population (or certainly some of them), or (more usefully)
b) change what we do to make it more effective.

Scientists and experts have been clear that the subgroup of people most at risk of Covid are also the people least likely to take the tests, and have suggested that improving financial support for people self-isolating after positive tests would improve effectiveness.

At the moment, we were told a week or two ago that we could all get unlimited tests free from any chemists (unless I imagined this, as I only saw it covered in the media for one day). However, that would be pointless for me and Mrs. Zico. We're both taking precautions to avoid infection and minimising our contacts, so having a twice-weekly confirmation that we're Covid-free would simply be a waste of our time and of government resources.

Returning to the thread title of "most impressive bits" I was particularly impressed with the early government commitment on furloughing workers, which was a huge ideological shift for a Conservative party, but someone somewhere recognised the realities of the new situation and made big decisions.

[dealtn]

If our current testing is made ineffective by the population, we can either
a) blame the population (or certainly some of them), or (more usefully)
b) change what we do to make it more effective.

Scientists and experts have been clear that the subgroup of people most at risk of Covid are also the people least likely to take the tests, and have suggested that improving financial support for people self-isolating after positive tests would improve effectiveness.

Scientists and experts appear to be clear those most at risk are aged 70+ and/or with other comorbidities and health conditions. Are you suggesting it is these groups that are least likely to take tests? That doesn't seem to be my understanding so if you can provide some evidence that would be appreciated.

[zico]

If our current testing is made ineffective by the population, we can either
a) blame the population (or certainly some of them), or (more usefully)
b) change what we do to make it more effective.

Scientists and experts have been clear that the subgroup of people most at risk of Covid are also the people least likely to take the tests, and have suggested that improving financial support for people self-isolating after positive tests would improve effectiveness.

Scientists and experts appear to be clear those most at risk are aged 70+ and/or with other comorbidities and health conditions. Are you suggesting it is these groups that are least likely to take tests? That doesn't seem to be my understanding so if you can provide some evidence that would be appreciated.

To clarify, I meant the people most at risk of getting and spreading Covid. There's been a lot of evidence that people in high-density housing and with low-paid manual jobs are much more exposed to Covid. We also know that these people are less likely to get Covid tests - in many cases, because they can't afford to self-isolate if they tested positive. If these groups continue to be exposed to Covid, then eventually they'll pass Covid onto the groups with higher risk of death from Covid - as you said, the elderly and those with co-morbidities.

[dealtn]

If our current testing is made ineffective by the population, we can either
a) blame the population (or certainly some of them), or (more usefully)
b) change what we do to make it more effective.

Scientists and experts have been clear that the subgroup of people most at risk of Covid are also the people least likely to take the tests, and have suggested that improving financial support for people self-isolating after positive tests would improve effectiveness.

Scientists and experts appear to be clear those most at risk are aged 70+ and/or with other comorbidities and health conditions. Are you suggesting it is these groups that are least likely to take tests? That doesn't seem to be my understanding so if you can provide some evidence that would be appreciated.

To clarify, I meant the people most at risk of getting and spreading Covid. There's been a lot of evidence that people in high-density housing and with low-paid manual jobs are much more exposed to Covid. We also know that these people are less likely to get Covid tests - in many cases, because they can't afford to self-isolate if they tested positive. If these groups continue to be exposed to Covid, then eventually they'll pass Covid onto the groups with higher risk of death from Covid - as you said, the elderly and those with co-morbidities.

Ok, I clearly misunderstood what you were saying.

[9873210]

What's not impressive or effective about testing more than a million people each day?

It's a measure of effort, not results.

I tentatively disagree. I can't unequivocally disagree because you don't define what "result" you are disappointed in but if you mean some level of suppression of the pandemic in the UK, either cases or deaths, then testing is a necessary but not sufficient effort in order for test/trace/isolate to have any downward effect on the cases which ultimately should put downward pressure on deaths as well. I haven't gone back and done a forensic analysis of the previous posts on this thread but I have the impression that none of those people praising testing was necessarily also saying that all of the other parts of the test/trace/isolate system are equally impressive. To criticise the effort expended on testing as wasted in terms of case suppression is a bit like saying that Samsung wasted its effort manufacturing my new TV because it is unable to receive any TV broadcasts when that failure to deliver its hoped-for results is because I haven't bothered to plug it into an aerial and scan for TV stations.

- Julian

Tests are useful, but neither necessary nor sufficient.

With low levels of cases trace and isolate can work without testing. The advantage of trace, isolate and test (unfortunate acronym) is that it significantly reduces the amount of isolation required. But the number of tests needed here is tens to a hundred times the number of case, which at least in August when things were more or less under control is far less than the number of tests actually done.

Using testing as the primary screen for test, trace and isolate requires far more tests than were actually done, something close to testing the entire potentially exposed population several times a week.

To me the best thing about testing seems that results were always timely (in a couple of days). Contrast this with the US were many tests results took longer than a week, at which point they are utterly useless. It is clear to me that testing should be LIFO rather than FIFO, so that if labs are overwhelmed you still get some useful results instead of no useful results.

[servodude]

It's a measure of effort, not results.

I tentatively disagree. I can't unequivocally disagree because you don't define what "result" you are disappointed in but if you mean some level of suppression of the pandemic in the UK, either cases or deaths, then testing is a necessary but not sufficient effort in order for test/trace/isolate to have any downward effect on the cases which ultimately should put downward pressure on deaths as well. I haven't gone back and done a forensic analysis of the previous posts on this thread but I have the impression that none of those people praising testing was necessarily also saying that all of the other parts of the test/trace/isolate system are equally impressive. To criticise the effort expended on testing as wasted in terms of case suppression is a bit like saying that Samsung wasted its effort manufacturing my new TV because it is unable to receive any TV broadcasts when that failure to deliver its hoped-for results is because I haven't bothered to plug it into an aerial and scan for TV stations.

- Julian

Tests are useful, but neither necessary nor sufficient.

With low levels of cases trace and isolate can work without testing. The advantage of trace, isolate and test (unfortunate acronym) is that it significantly reduces the amount of isolation required. But the number of tests needed here is tens to a hundred times the number of case, which at least in August when things were more or less under control is far less than the number of tests actually done.

Using testing as the primary screen for test, trace and isolate requires far more tests than were actually done, something close to testing the entire potentially exposed population several times a week.

To me the best thing about testing seems that results were always timely (in a couple of days). Contrast this with the US were many tests results took longer than a week, at which point they are utterly useless. It is clear to me that testing should be LIFO rather than FIFO, so that if labs are overwhelmed you still get some useful results instead of no useful results.

I get what you are saying (and no disagreement re sufficiency)
but...
In the low case count circumstances you describe timely testing is still required for confirmation/rejection of cases and (especially given the pre/asymptomatic issues surrounding covid) screening of contacts
- and for surveillance in general

so testing would still be necessary
- but you wouldn't need to be doing anywhere near 1% of the population per day; if you were you'd probably be wasting energy and resources which could be better spent elsewhere

which leads a bit to the salient point made in:

There's been a lot of evidence that people in high-density housing and with low-paid manual jobs are much more exposed to Covid. We also know that these people are less likely to get Covid tests - in many cases, because they can't afford to self-isolate if they tested positive. If these groups continue to be exposed to Covid, then eventually they'll pass Covid onto the groups with higher risk of death from Covid - as you said, the elderly and those with co-morbidities

it is most beneficial from a reduction of spread perspective if people isolate while waiting for results and if they then test positive
so if you want an effective test scheme: use the money not spent on the tests you don't need to make the ones you are doing more useful
along the lines of:
- get the case count low
- compensate people if they lose income due to seeking a test
- compensate them if they test positive
- rinse and repeat - to keep the case count low

much more satisfying to complete the game than grind out a meaningless high score crushing simple mobs

- sd

[9873210]

I get what you are saying (and no disagreement re sufficiency)
but...
In the low case count circumstances you describe timely testing is still required for confirmation/rejection of cases and (especially given the pre/asymptomatic issues surrounding covid) screening of contacts
- and for surveillance in general

so testing would still be necessary
- but you wouldn't need to be doing anywhere near 1% of the population per day; if you were you'd probably be wasting energy and resources which could be better spent elsewhere

According to the CDC a 14 day symptomless quarantine is more than 99.9% effective. If symptoms occur appropriately timed isolations are equally effective. You do not need tests to effectively trace and isolate. A calendar and clinical judgement are enough.

However tests at the end of quarantine can reduce the period by several days. This is humane and cost effective. It should be done if tests are available but is not necessary.

Testing at the beginning of quarantine is more useful but also not necessary. Once a contact tests negative you don't need to trace and quarantine the contact's contacts. This reduces the cost of tracing and isolating at any level of virus circulation and will allow effective tracing at a higher level of circulation.

it is most beneficial from a reduction of spread perspective if people isolate while waiting for results and if they then test positive
so if you want an effective test scheme: use the money not spent on the tests you don't need to make the ones you are doing more useful
along the lines of:
- get the case count low
- compensate people if they lose income due to seeking a test
- compensate them if they test positive
- rinse and repeat - to keep the case count low

It's also worth working on getting test results fast. If you find a contact has been in a crowd getting a negative result in a couple of hours would save a lot of contact tracing and a lot of anguish in the people who don't have to isolate for a few days waiting for a result.

At some level of testing a single test result in a few hours would be better than tens of test results in a few days or thousands of test results in a week. A simple count of test results is pleasing to bureaucrats but does not measure what really matters.

[dealtn]

At some level of testing a single test result in a few hours would be better than tens of test results in a few days or thousands of test results in a week. A simple count of test results is pleasing to bureaucrats but does not measure what really matters.

True. But on another level, tens of thousands of test results in 30 minutes, and thousands of (more accurate) test results in a day are still "impressive" currently.

[servodude]

According to the CDC a 14 day symptomless quarantine is more than 99.9% effective. If symptoms occur appropriately timed isolations are equally effective. You do not need tests to effectively trace and isolate. A calendar and clinical judgement are enough

That still leaves holes in quarantine

We've seen people catch COVID in quarantine and leave before they've noticed - without any testing you'd never know until its spreading symptomatically in the population (and without tests you'd be Tanzania even then)

There are around 17k tests performed in Victoria, AUS every day
- turn around is less than 24hrs
- positivity rate of them would be best measured in parts per million

Without tests, under the scheme you suggest, there would be 17k people starting a two week isolation everyday
- which would probably work, but would be a helluva lot less efficient , and would be relying on a lot more assumptions

All different parts of the Swiss cheese
-sd

[servodude]

It's also worth working on getting test results fast. If you find a contact has been in a crowd getting a negative result in a couple of hours would save a lot of contact tracing and a lot of anguish in the people who don't have to isolate for a few days waiting for a result.

Absolutely agree!

To me that's all part of the "act fast - act hard" method that seems to have worked well for places that went that route
The incubation period required to develop enough virus to return a positive result is another reason that testing needs to be done in a considered way to be effective

The box ticking approach that if someone's returned a negative test three days before they're "clear" has repeatedly been shown to be quite ineffective
- but it persists

At some level of testing a single test result in a few hours would be better than tens of test results in a few days or thousands of test results in a week. A simple count of test results is pleasing to bureaucrats but does not measure what really matter

Which is why I like things such as https://virolens.keyoptions.com/

But unfortunately to many bureaucrats - keeping them pleased is all that matters


- sd

[9873210]

That still leaves holes in quarantine

We've seen people catch COVID in quarantine and leave before they've noticed - without any testing you'd never know until its spreading symptomatically in the population (and without tests you'd be Tanzania even then)

There are around 17k tests performed in Victoria, AUS every day
- turn around is less than 24hrs
- positivity rate of them would be best measured in parts per million

Without tests, under the scheme you suggest, there would be 17k people starting a two week isolation everyday
- which would probably work, but would be a helluva lot less efficient , and would be relying on a lot more assumptions

All different parts of the Swiss cheese
-sd

A person in quarantine who does not already have COVID should be at lower risk of catching it than the general population. If people are catching COVID in quarantine it's not being done right. Isolate means isolate, not throw everybody whose been exposed into the Black Hole of Calcutta. And testing at the end of quarantine does not close the hole. Somebody exposed towards the end of quarantine could be incubating but still test negative.

17k tests per day in Victoria scales to 175k test per day in the UK. Controlling COVID is something to brag about, 2 million test per day is not. Ten times as many tests with worse results is a sign we are doing something wrong.

It's far better to carefully apply a smear of cream cheese, without any holes, than to use layer upon layer of Swiss and hope the holes don't line up. If you have to use Swiss find a carpenter who knows how to make a Dutchman and patch the freaking holes.

We've known how to contain COVID for 9 months. We've had the resources to do so. We've spent the resources, but often on things that do not work.

[servodude]

A person in quarantine who does not already have COVID should be at lower risk of catching it than the general population. If people are catching COVID in quarantine it's not being done right

Indeed. But the first thing in getting an effective quarantine under way is starting it
- as a result the premises in use aren't generally built for the purpose and it appears that airborne transmission can be more of a problem than was initially expected
- so while testing in and of itself doesn't stop the spread of anything; it does allow monitoring and review of what does help

-sd

[9873210]

A person in quarantine who does not already have COVID should be at lower risk of catching it than the general population. If people are catching COVID in quarantine it's not being done right

Indeed. But the first thing in getting an effective quarantine under way is starting it
- as a result the premises in use aren't generally built for the purpose and it appears that airborne transmission can be more of a problem than was initially expected
- so while testing in and of itself doesn't stop the spread of anything; it does allow monitoring and review of what does help

-sd

The testing in this case should be viewed as research/quality control. Locate leaks in quarantine and fix them. This does not require 100% coverage. Using testing to cover for leaky quarantines is yet another way of not doing it right.

Testing is useful, but testing 3% of the population per day is far too low to use testing as a primary control measure, but a huge excessive for more targeted uses.

[TUK020]

Can we really claim a world besting genomic sequencing programme? I do not know but would be interested to have any references to this. The whole subject is so international I think it might be difficult for us Brits to claim as our own. I stand to be corrected though.

It is a heartening thread though and thanks to Mike4.

Dod

I have read (but don't have a record of the references to hand) that some 70% of all COVID sample genome sequencing to track mutations/variants has been done in the UK, and some 80% of this portion has been done in a single facility (The Sanger Institute, just south of Cambridge).

[Dod101]

That is interesting TUK020. I will see if I can get any more on this. I am just an interested bystander. Thank goodness for the Wellcome Foundation.

Dod

[TUK020]

All of this work on genome sequencing has also led to a much better handle on the rate of mutation in coronaviruses.
In general, once viruses have made a 'species hop', they tend to mutate at a predictable rate, and tend to become more infectious, but less virulent.

The 'common cold' is mostly a collection of rhinoviruses, but also includes 4 coronaviruses.

There is a hypothesis that these 4 common cold coronaviruses all had a common root. The rate of mutation would indicate that this common ancestor is about one and a quarter centuries ago - this would line up with the "Russian Flu" pandemic of 1890.

I wonder if the new mRNA vaccine technology will be able to sort a lot of the common cold in due course.