Coronavirus testing

[Skimpot flyer]

How can you have a system that produces results on tests that have not taken place?

We already have that system in place.
This video shows empty testing centres at Warrington, Woodford Green (east London), Greenwich, Bedford, Bidston, Eastbourne, Gosport, Hastings, Leeds, and Coventry

 

[kristiang85]

This was an interesting observation someone has made on Twitter (original thread here: https://twitter.com/ClareCraigPath/status/1321365778504028161/photo/1)

Apparently if you look at the % of positive tests in Scotland, every week without fail they peak on Fridays and Saturdays (and you're twice as likely to test positive on a Friday as on a Sunday). I can't think of any rational explanation for this - what do others think?

Remember, this is the % of positive tests, not the raw number, so it should be fairly consistent you'd think across all days.

 

[trebor79]

This was an interesting observation someone has made on Twitter (original thread here: https://twitter.com/ClareCraigPath/status/1321365778504028161/photo/1)

Apparently if you look at the % of positive tests in Scotland, every week without fail they peak on Fridays and Saturdays (and you're twice as likely to test positive on a Friday as on a Sunday). I can't think of any rational explanation for this - what do others think?

Remember, this is the % of positive tests, not the raw number, so it should be fairly consistent you'd think across all days.

Could be all sorts of things. Most likely something to do with fewer people visiting healthcare settings like GPs and hospital A&E at the weekend and being tested. So perhaps more "worried well" and possible contacts being tested at weekends and fewer being tested because a healthcare professional thinks they may be infected.
Whatever it is, it'll be down to a different cohort of people being tested on different days of the week rather than anything sinister.

 

[Skimpot flyer]

This was an interesting observation someone has made on Twitter (original thread here: https://twitter.com/ClareCraigPath/status/1321365778504028161/photo/1)

Apparently if you look at the % of positive tests in Scotland, every week without fail they peak on Fridays and Saturdays (and you're twice as likely to test positive on a Friday as on a Sunday). I can't think of any rational explanation for this - what do others think?

Remember, this is the % of positive tests, not the raw number, so it should be fairly consistent you'd think across all days.

The virus is very social... it likes to go out more on weekends???
Seriously, why has nobody commented on the video I shared, showing empty test centres in multiple locations across England? Where are the test numbers coming from ?

 

[kristiang85]

The virus is very social... it likes to go out more on weekends???
Seriously, why has nobody commented on the video I shared, showing empty test centres in multiple locations across England? Where are the test numbers coming from ?

Oh I've been seeing these too, I just don't have any reasonable answers though... surely the figures aren't just brazenly made up?

 

[adc82140]

The virus is very social... it likes to go out more on weekends???
Seriously, why has nobody commented on the video I shared, showing empty test centres in multiple locations across England? Where are the test numbers coming from ?

The test centres are empty because the testing capacity far outweighs the lab capacity. It's easy to set up a test centre in a car park. You need Heras fencing, traffic cones, a tent and a handful of military or civilian people to run it. The government can then say "look at what we've set up. Aren't we great".

Setting up a lab requires the equipment, the specialist staff etc etc.

There's no point in doing the tests if there's nowhere to process them. We're already seeing days long delays in getting results.

 

[Richard Scott]

The virus is very social... it likes to go out more on weekends???
Seriously, why has nobody commented on the video I shared, showing empty test centres in multiple locations across England? Where are the test numbers coming from ?

If test centres are empty in these locations there can't be any/many positive tests so why are there any restrictions?
Maybe above post answered that one. Read everything before replying!!!

 

[hwl]

If test centres are empty in these locations there can't be any/many positive tests so why are there any restrictions?
Maybe above post answered that one. Read everything before replying!!!

The post above provides most of the answer, the number of testing centers has been vastly increased so they are more local so people don't have to travel so far. Hence the average number of samples taken per centre has been coming down over time even though the lab capacity has been increasing albeit at much slower rate.
The WHO guidance for adequate testing capacity (whole system) is that the test positivity rate should be less than 5% (1 in 20) including all the medical + care staff testing. Hence many won't be ill. The test positivity rate from yesterday's data was 8.74% hence the lack of lab capacity is still an issue.

 

[Domh245]

It's worth remembering that a couple of weeks ago there was a big news story about Roche having issues with their supply chain/distribution that could limit the number of tests being processed. Has that been resovled?

 

[Peter Mugridge]

The latest appears to be that 10% of tests from across the summer have been moved back from the "within 24 hours" to the "24 to 48 hours" turnaround categories.

Apparently ( confirmation welcomed... ) they failed to take into account the clocks going forwards in spring and didn't notice until last weekend when the clocks went back...




Edited: typo

 

[GRALISTAIR]

They stuck a swab stick up both nostrils and really moved it around. It was uncomfortable and I really wanted to sneeze. Took just under a minute for me.

 

[DustyBin]

Somebody posted this shot of some testing paperwork on the pistonheads forum. Can anybody else see the potential problem here?....

 

[6862]

Somebody posted this shot of some testing paperwork on the pistonheads forum. Can anybody else see the potential problem here?....

The idea is that all the samples can be tested in one go (much quicker). If the mixture is negative for the virus in the PCR test, none of the 5 have it. If the mixture is positive, at least one has it and individuals can then be tested separately. Saves on the chemicals used in testing apparently. I read that it is how most tests are done in poorer countries with less resources.

 

[DustyBin]

The idea is that all the samples can be tested in one go (much quicker). If the mixture is negative for the virus in the PCR test, none of the 5 have it. If the mixture is positive, at least one has it and individuals can then be tested separately. Saves on the chemicals used in testing apparently. I read that it is how most tests are done in poorer countries with less resources.

Thanks for the explanation. My concern was that cross contamination would lead to five positive tests....

 

[Domh245]

The idea is that all the samples can be tested in one go (much quicker). If the mixture is negative for the virus in the PCR test, none of the 5 have it. If the mixture is positive, at least one has it and individuals can then be tested separately. Saves on the chemicals used in testing apparently. I read that it is how most tests are done in poorer countries with less resources.

Exactly this, although it's worth noting it isn't used exclusively in poorer countries with less resources!

This video explains it in a bit more detail, as well as some of the other challenges of the testing system (from a US perspective)

 

[6862]

Exactly this, although it's worth noting it isn't used exclusively in poorer countries with less resources!

Yes, it is used elsewhere, but it is particularly commonly used in poorer countries. I think it's a very good idea!

 

[MikeWM]

I see Slovakia have gone down the 'forced testing by the army' route. How long until we follow?

https://www.theguardian.com/world/2020/nov/01/half-slovakia-population-covid-tested-covid-one-day

More than 40,000 medics and support teams of soldiers, police, administrative workers and volunteers staffed about 5,000 sites to administer the antigen swab tests. The testing was free and voluntary, but the government has said it will impose a lockdown on those who do not participate, including a ban on going to work.

(emphasis mine)

Interesting use of the word 'voluntary' there.

 

[WelshBluebird]

If we look at it from another angle, if someone books an appointment, do they "check in" when they arrive? I don't actually know how it works. If they do, but then have to wait and decide to leave the system may flag a result as lost if it cannot find one. Given this person is only usually supposed to get this test if they have symptoms, IF they cannot display NO RESULT then is it better to default to NEGATIVE where they'll go about their daily business and could infect others that might not be well enough to deal with it, or default to POSITIVE, thus reducing that risk.

That just isn't what happens.

1. If you book a test but do not take it, then no sample is tested and so there is no result.
2. If you do take a test but the swab isn't conclusive for whatever reason, there is a specific result of inconclusive / unclear that comes back whichs means you should take another test. It does not get counted as positive or negative.

We already have that system in place.
This video shows empty testing centres at Warrington, Woodford Green (east London), Greenwich, Bedford, Bidston, Eastbourne, Gosport, Hastings, Leeds, and Coventry

Load of rubbish from a biased channel.
There are two huge reasons why the test sites may be quieter than what many people may think they should be:

1. We have more test sites now to make it easier for people to get tested. Back in the first lockdown Bristol had one testing site and that was at the airport way out of the city that you had to drive to. Now there is also one up at UWE in the north and two walk in ones near the city centre. More test sites means the the people who are getting tested are spread out across more sites - which directly means each individual site is quieter.
2. The main limit on testing capacity is at the labs rather than at the test sites. The test sites themselves have the capacity to deal with a lot more people - but their usage is being limited because of the lab testing that needs to take place.

 

[adc82140]

Off work today. Good old fashioned rhinovirus. I feel crap. However none of the big three symptoms. No fever, no cough, and I can still smell the marmite jar.

But several people have said I should get a test (including some who should know better). This sort of thing is what's clogging up the testing system.

 

[DustyBin]

Off work today. Good old fashioned rhinovirus. I feel crap. However none of the big three symptoms. No fever, no cough, and I can still smell the marmite jar.

But several people have said I should get a test (including some who should know better). This sort of thing is what's clogging up the testing system.

I can well imagine, I think it’s a mixture of paranoia and obsession!

 

[Bantamzen]

Off work today. Good old fashioned rhinovirus. I feel crap. However none of the big three symptoms. No fever, no cough, and I can still smell the marmite jar.

You've been smelling the marmite? Seek help immediately....

But several people have said I should get a test (including some who should know better). This sort of thing is what's clogging up the testing system.

I think the time has come for the government to start educating people on when they should and should not seek a test. There are probably way too many people wanting a test for just feeling a bit crap.

 

[WelshBluebird]

I think the time has come for the government to start educating people on when they should and should not seek a test. There are probably way too many people wanting a test for just feeling a bit crap.

It doesn't help when:

• Some employers are sending staff home and won't allow them back without having had a test for things like having a slight (but fairly normal for this time of year) cough that clearly isn't COVID related.
• The rules around self isolating when a member of your household gets a test mean it is much better for you to also get a test at the same time and hopefully get a negative result.
• Some of the advise people can get (especially from things like 111) is pretty risk adverse - some of the advice is basically if you aren't sure if you should get a test or not (or the person advising you isn't sure), then get one anyway just incase.

 

[adc82140]

A week in to my flu like illness my sense of smell has gone. Ordered a test, and the household is now isolating pending the result. I still think it's flu, every time I get something like this the sense of smell goes, but now I have one of the big 3 symptoms I have to follow the rules.

 

[Crossover]

It doesn't help when:

• Some employers are sending staff home and won't allow them back without having had a test for things like having a slight (but fairly normal for this time of year) cough that clearly isn't COVID related.

"Better" than that, I am aware of one employer who twice, having had one person in the office test positive has ordered the office to close and all staff to be tested. Again, TWICE!

 

[island]

"Better" than that, I am aware of one employer who twice, having had one person in the office test positive has ordered the office to close and all staff to be tested. Again, TWICE!

I hope that employer is paying for the costs of the tests privately and not burdening the NHS with frivolous testing.

 

[greyman42]

Thanks for the explanation. My concern was that cross contamination would lead to five positive tests....

I would imagine this to be the reality.

 

[adc82140]

Afternoon all,

Having been convinced I had a cold, not so sure now. Still awaiting the results of a Covid test, getting frustrated now. I'm no longer feeling ill as such, just utterly exhausted. More so than I have ever been before. The breathlessness is a toil as well. I tried to do a bit of light gardening earlier, but gave up after 10 minutes and had to have an hour's sleep to recover. I've started eating a bit, but nowhere near my normal intake. I think the breathing might be more anxiety based, as it never wakes me up.

As for the test itself, I did the home test. To be honest it wasn't as bad as I imagined. After I'd done it I also decided to shave off a week's worth of stubble, and that was definitely the more unpleasant job.

Am I still a lockdown sceptic? Yes. Nothing's changed there. A couple of times last week I was convinced it was the end. (melodrama alert) I was peeved that if it was I'd just wasted the previous year.

 

[Cowley]

Afternoon all,

Having been convinced I had a cold, not so sure now. Still awaiting the results of a Covid test, getting frustrated now. I'm no longer feeling ill as such, just utterly exhausted. More so than I have ever been before. The breathlessness is a toil as well. I tried to do a bit of light gardening earlier, but gave up after 10 minutes and had to have an hour's sleep to recover. I've started eating a bit, but nowhere near my normal intake. I think the breathing might be more anxiety based, as it never wakes me up.

As for the test itself, I did the home test. To be honest it wasn't as bad as I imagined. After I'd done it I also decided to shave off a week's worth of stubble, and that was definitely the more unpleasant job.

Am I still a lockdown sceptic? Yes. Nothing's changed there. A couple of times last week I was convinced it was the end. (melodrama alert) I was peeved that if it was I'd just wasted the previous year.

All the best to you and the family. Hope you’re on the mend soon enough

 

[adc82140]

The judges have their scores. Coronavirus: Positive.

I'd like to take this opportunity to deny any link between myself and Katya Jones.

 

[brad465]

Current results from Liverpool suggest 700 cases picked up in their mass testing programme were asymptomatic:

Covid-19: Liverpool mass-testing finds 700 cases with no symptoms

Nearly 100,000 people have been tested for the virus over 10 days in Liverpool.

www.bbc.co.uk

A mass Covid-19 testing trial in Liverpool has found 700 people unwittingly had the virus.

Public Health England director Dr Susan Hopkins said nearly 100,000 people had been tested over the last 10 days.

She stressed that these positive cases would have not been detected otherwise.

About 2,000 soldiers have been deployed in the city for the project, which was intended to run for an initial period of 10 to 14 days.

Devices which give results within an hour have been used to test people in the city since the scheme began on 6 November.

There's nothing as yet in this article about how many tested had symptoms, although of the 100k tested this value would constitute 0.7% of the whole population had it with no symptoms, when going by figures in other survey studies like Zoe and from the ONS, the highest proportion infected is likely to be around 1-3%.

I do think not enough positive stuff is said about asymptomatic infections, while they may help it spread unknowingly they are of course a sizeable proportion of virtually harmless infections to the affected individuals.