Mass Testing (Le test en masse)

[Chedney Honks]

Another new game changer from the brain boxes over at Company's House. Robbed off China circa seven months ago.

Weekly tests available for all tier 3 vectors and anyone anywhere working in a meat packing plant or prison (don't make the obvious joke).

Repeat testing going to be trialled in Liverpool, whereby close contacts of confirmed cases can test their way out of isolation by doing a test every day for a week. If that works OK, they'll roll it out in December to care homes and the NHS. The shit munchers will get repeat testing from January (and we'll need it haha!). Nothing about schools or universities but the alternative is unpalatable.

BBC headline to announce these new measures:

Gyms and all shops to reopen after English lockdown

[Zetetic]

Have we had any meaningful public statistics out of Liverpool yet?

It feels like rapid turnaround mass-testing could be a useful tool, but that we still haven't really put the right context in place (that will get people who pose the greatest risk to be tested and reliably isolate).

[BlodwynPig]

Have we had any meaningful public statistics out of Liverpool yet?

It feels like rapid turnaround mass-testing could be a useful tool, but that we still haven't really put the right context in place (that will get people who pose the greatest risk to be tested and reliably isolate).

Just doing that now for Br*nze meeting. Really need testing/public health eyes on it as I cannot make any conclusion from the results. Seems like - no insights.

[Zetetic]

It feels like our PH/epi lot have had no real interest in the LFT data in MT - insisting that they only care about the follow-up PCR tests. Weird to me, particularly given the lag. (I wonder if they'll change their tune by the end of today.)

Would be fascinating to know how Liverpool's mass testing prevalence compared with your other indicators, but I suspect you can't share.

Variation in testing take-up by demographics and area (and by extension: deprivation? car and other travel access? employment sectors?) seem like things we should be seeing stuff in the public on by now...

[BlodwynPig]

It feels like our PH/epi lot have had no real interest in the LFT data in MT - insisting that they only care about the follow-up PCR tests. Weird to me, particularly given the lag. (I wonder if they'll change their tune by the end of today.)

Would be fascinating to know how Liverpool's mass testing prevalence compared with your other indicators, but I suspect you can't share.

Variation in testing take-up by demographics and area (and by extension: deprivation? car and other travel access? employment sectors?) seem like things we should be seeing stuff in the public on by now...

got an MEng starting on that last question today.

don't have the latest test data, ww ahead of the game.

[Chedney Honks]

Send through the data to gerontophile3000@hotmail.com and I'll have a good nosey.

[Jasha]

Get a test to squeeze the disease

[lipsink]

Till the Season to be Jolly careful

Fuck me.

[BlodwynPig]

Send through the data to gerontophile3000@hotmail.com and I'll have a good nosey.

Sent, OFF SENS

[Zetetic]

https://twitter.com/katierazz/status/1330999988151848961

As I feared, people won't access mass testing if it's going to hurt them to do so.

(I've literally only spent 40 seconds on it today, but there's already evidence of similar effect here.)

[BlodwynPig]

https://twitter.com/katierazz/status/1330999988151848961

As I feared, people won't access mass testing if it's going to hurt them to do so.

(I've literally only spent 40 seconds on it today, but there's already evidence of similar effect here.)

Yeh, got some serious push back from PH Newcastle on the MT side...brutal but spot on.

Did you get my messages btw? (ps. I said you were an old friend, just in case he or others probe the link).

[Zetetic]

We're seeing the deprivation effect here, and it's not small.

Worries that people aren't seeking follow-up PCR tests.

Both possible to address, but whether anyone will...

[Zetetic]

Any evaluation of Liverpool out yet?

[bgmnts]

Any evaluation of Liverpool out yet?

Good football team, good bands, annoying high pitched accents.

7/10

[Zetetic]

University of Birmingham data:
https://twitter.com/deeksj/status/1340975390412685312

Not encouraging.

[olliebean]

I'm never quite sure of the difference between sensitivity and specificity. 3% sensitivity, that means that 97% of cases will be missed, right?

[Zetetic]

Yes.

Their claimed figures are:

Population of 7183 students.
Estimated 62 students with COVID-19[nb]This is based on the positivity rate discovered via PCR-testing 710 student at random and 6 of these testing postive.[/nb]
Observed 2 students with lateral flow device positives.

Meaning that they believe 60 positive cases were missed[nb]and 60 out of 62 is 97%[/nb].

[shiftwork2]

We've been working on a sensitivity of up to 70% when self-administered by someone who knows what they're doing for the Innova tests.  We've been doing them twice a week alongside a weekly PCR.  3% is shocking but I think this chap really should wait for peer review before he sticks it on twitter with the words 'madness' and 'dangerous'.  Is that how academia works these days?

[Zetetic]

(I've made my language more cautious accordingly. Fair point.)

[RDRR]

The low numbers of positives these tests are reporting, particularly at universities, do seem like they might be too good to be true, don't they? And while double-testing is advised it doesn't seem to be well enforced. Lots of students here got tested just once, which seems like it could offer a dangerous level of false reassurance (even if the sensitivity is nearer 50% as previously reported).

Clearly proportions are dodgy with such low numbers, and sensitivity is higher when administered by those with training, while factors like age might play an important part. But if the tests are A) frequently self-administered by those without training and B) used as diagnostic, then it's not looking great. In some cases it does seem plausible they could do more harm than good.

[shiftwork2]

Alright, fag packet time.

So my Trust has picked up 28 PCR-confirmed positives with Innova over the past three weeks.  At a guess I'd say 3/4 of people are doing them so that's around 3500 punters.  So, 0.25% which fits quite nicely with the positive testing rate for this Tier 4 region.  Roll in a sensitivity of 3% and we would have picked up - what - 2, instead of 28?

Is he suggesting that institutions all over the country haven't been keeping a close enough eye on the data to pick up on a sensitivity 20 times less than expected?

[Zetetic]

Different situations, isn't it?

As you say, your Trust is doing them twice weekly. Presumably following training? Presumably by people used to jabbing stuff into humans (at least those most likely to catch it)?

That's quite a different situation to students or members of the general public doing it once or maybe twice at all, with very limited instructions and often with strong disincentives for actually getting a positive[nb]Noting that some healthcare staff will also be disincentivised, but many won't.[/nb].

[Zetetic]

The Ct values are worth paying attention to as well, and that opens up the question of sensitivity with respect to what?

Maybe some of your 28 would have been picked up by a PCR a week earlier (in theory, setting aside the lag of getting the swab analysed...)?  Would that would have had any actual impact?

[Zetetic]

https://www.gov.uk/government/publications/community-testing-explainer/community-testing-a-guide-for-local-delivery#annex-b

"In field evaluations, such as Liverpool, these tests still perform effectively and detect at least 50% of all PCR positive individuals and more than 70% of individuals with higher viral loads in both symptomatic and asymptomatic individuals."

[shiftwork2]

Twice a week - yep, didn't include that.  No training at all - there's a leaflet in the box.  Goes far enough up that you pull a Frankie Howerd face but not so far as to have it enter your brain like the staff-performed PCR.  And it's the whole establishment which includes lots of non-clinical people.  Debatable how much use any clinical training is anyway when it comes to doing it on yourself.

The weekly PCR is currently for a small minority (5%?) dealing with high-risk patients so probably insufficient numbers to say.

[Zetetic]

Not just the twice-a-week, but week-after-week. Understood re lack of training.

How many of the 28 are clinical, do you know? (Mostly out of nosiness.)

I would quite like public lateral flow testing not to be completely shit, to be clear, both for the general "no more COVID-19" reasons but also because I apparently convinced people to keep LFD test centres open in some of the poorest parts of my country for longer[nb]As in Liverpool, deprivation massively influenced mass-testing take-up.[/nb] and don't want more blood on my hands.

[Zetetic]

"Moonshot" dead.

[Shoulders?-Stomach!]

Proposal to change 'Le test en masse' to 'L'enorme'

Cheers

[BlodwynPig]

"Moonshot" dead.

weeks ago, Z. Not heard that for weeks. LOL. They're all having parties, that side of the biz. Giving it large in the Friday chill Teams chat. DEAD

[BlodwynPig]

I can reveal that our biggest success story (and I can't obviously reveal details) has been in

Spoiler alert

Exeter

[close]

. TOP TOP City. Any CaB Devonians on here. You should be proud of your public health "servants".