Coronavirus (2021) thread

[Rammy Blue]

Can expect that to shoot up again as LFTs are rolled out in schools - 2 tests per pupil per week, must be a million a day easily?

Yeah, I think we can pretty much ignore the total test numbers and positivity rate now, it’s just the cases figure that matters.

 

[Healdplace]

Yeah, I think we can pretty much ignore the total test numbers and positivity rate now, it’s just the cases figure that matters.

I think that is likely the case when you get to testing about one in every 80 persons living in the country every day.

Though the positivity number has plummeted it is possibly also MORE reflective of the 'real' positivity number though - in the sense of those who are positive in the population because the old way only really measured those with symptoms or reason to suspect they were ill. When Covid can often be asymptomatic or sufficiently mild it would not in the past have generated a test.

 

[roubaixtuesday]

Yeah, I think we can pretty much ignore the total test numbers and positivity rate now, it’s just the cases figure that matters.

I think case numbers may instantly become unreliable as school testing comes online - LFT false positives may dominate the numbers as IIRC the fake positive rate is far higher than PCR. I wonder if PCR testing will be/is split out.

 

[Healdplace]

Regional Scoreboard:

The regions are starting to come together into a little separated whole - very different from when two months back we had 10,000 - 15,000 or so for several of the southern regions like London and 5000 - 6000 for the rest bar the smaller areas such as NE and SW which were well up but only at 2000 or so.

Now for several days everyone has tumbled and been in 3 figures basically spread between 300 and 900.

This is possibly the best indicator of a pandemic under control. Large swathes of uniformity.

East: - up 20 to 476

London :- up 119 to 623

South East: - up 66 to 556

South West: - up 29 to 303



East Midlands: - up 103 to 760

West Midlands: - up 55 to 810



North East:- down 56 to 351

Yorkshire: - down 21 to 902

And

North West : - down 34 to 889

Meaning Yorkshire has become the most infected area. Though as you see by just 13.

The uniformity is further shown by the past run of numbers since NW fell below 1000 for the first time in 2021 - five days ago: -

880, 808, 889, 923 and 889.

As flat line as you can get.

Which is either good or bad whichever way you want to look at it.

 

[shemnel]

I think case numbers may instantly become unreliable as school testing comes online - LFT false positives may dominate the numbers as IIRC the fake positive rate is far higher than PCR. I wonder if PCR testing will be/is split out.

Specificity = 99.7%
Sensitivity = 76.8%

so on a population of 10,000 with a true disease prevalence of 1% (i.e. 100 actual cases), LFT can expect, roughly, to;
- pick up 9,870 true negatives
- pick up 77 true positives
- report 23 false negatives
- report 30 false positives

https://www.ox.ac.uk/sites/files/oxford/media_wysiwyg/UK%20evaluation_PHE%20Porton%20Down%20%20University%20of%20Oxford_final.pdf

Evidence summary for lateral flow devices (LFD) in relation to care homes

www.gov.uk

 

[roubaixtuesday]

Specificity = 99.7%
Sensitivity = 76.8%

https://www.ox.ac.uk/sites/files/oxford/media_wysiwyg/UK%20evaluation_PHE%20Porton%20Down%20%20University%20of%20Oxford_final.pdf

Evidence summary for lateral flow devices (LFD) in relation to care homes

www.gov.uk

Which makes 3,000 false positives expected daily if we test a million pupils.

If that's reported as part of the main testing results it will make them meaningless as a way of tracking the pandemic.

 

[shemnel]

Which makes 3,000 false positives expected daily if we test a million pupils.

If that's reported as part of the main testing results it will make them meaningless as a way of tracking the pandemic.

completely correct. if it follows the published parameters.
it was strange liverpool had such low positivity with it though

actually maybe not, they were testing a smallish sample, so a small false +ve, and symptomatic were told to stay away so they were generally -ve anwyay

 

[roubaixtuesday]

completely correct. if it follows the published parameters.
it was strange liverpool had such low positivity with it though

actually maybe not, they were testing a smallish sample, so a small false +ve, and symptomatic were told to stay away so they were generally -ve anwyay

Not looked at Liverpool.

I suspect self administered tests by children with those sensitivity and specificity numbers in expert hands are literally worse than useless. Hopefully I'm wrong.

 

[shemnel]

Not looked at Liverpool.

I suspect self administered tests by children with those sensitivity and specificity numbers in expert hands are literally worse than useless. Hopefully I'm wrong.

didnt they actually buy 400m of them and then the MHRA said they were no good? also, thought they were denied use for schools as recently as January but may be mistaken

 

[Healdplace]

GM highlights:

Unfortunately after an amazing day here yesterday not so today.

One of the worst in weeks.

Though at these low numbers that is relative and small changes are magnified.

Despite the NW as a region falling by 34 - Greater Manchester went UP by 87 to its highest number in 6 days.

At 434 (a number last week which would have been great) this bumped its % of the NW up a lot - highest daily rise in weeks - 11.2% in one day to 48.8%.

Only Bury actually fell (by 4) - though Trafford equalled its low score of 17 from yesterday to be yet again miles ahead in GM.

Manchester went up the most to 83 but has now been sub 100 for 6 days and if you count the score of exactly 100 in the middle as 'up to 100' then for 8 straight days.

Bolton, Rochdale and Wigan had modest rises to be over 50.

Everyone else was up between 2 and 5 only on the day. And well down week to week as was almost everywhere.

So a blip rather than a problem as day to day fluctuations will always happen - especially when numbers are low.

And we have not now had a single GM borough with a three figure total in 6 days and it was months before we could say that when it first happened last week.