Lateral Flow

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Please bare with me

So the past couple of days I have been feeling not myself, so yesterday morning I done a lateral flow test I got a very faint positive but ON the 30 min mark.
Yesterday afternoon I done another one again I was feeling tired, bad head and generally off again I got another faint line but was definitely darker but again was 26 mins into the timer and definitely got darker after the 30 mins.

So later on after my daughter came in from school I thought I would do a control one knowing she felt fine just to see if hers also came up with the faint line (I had also booked a pcr for this morning to be on the safe side and have isolated) again I got the faint positive but again this was more or less the 30 min mark that it showed up but my daughter was a stark white negative one line no other faint lines.

I have been for my pcr this morning still feeling generally off tinnitus, headache's and a bit of nausea.

Has anyone else had this with the tests and been for a pcr and had negative or positive result??, it says in the book not to read after 30 mins but my lines were appearing and getting slightly darker a couple of mins after the 30mins

Definitely not a faint positive!
Flow flex was the one that caught mine earlier than all the other brands! X

Apparently tap water does the same thing but it’s got something to do with the acid and when it’s put straight onto the test that’s why it brings up positive because the vile of liquid you put the swab into is a buffer that neutralises the acid (just what I read)

I have had at least one false positive with flow flex early December but all others after that were totally negative (again it was a faint line) but since yesterday all 4 lft’s I have taken are showing 2 lines they are quiet faint lines none of them pop up instantly but are still there none the less.

I keep going through spells of feeling unwell and then feeling fine, having said that the early days of delta I was convinced my results were going to be negative because I was doing the same. Feeling run down then feeling fine and getting on with housework etc.

I will definitely update when I get the results back

Well my PCR results came back negative this morning

I am full of a head cold so I wonder if it’s picking that up, I will do another lateral flow today and see if the lines come up thicker or faster but if not I gather it just picking something else up!

Good to hear the PCR is negative. I wouldn’t have thought you need to do any more LF tests now? I think we all perhaps need to try and reduce our use of LF testing unless necessary. They are free to us, but the financial implications of all this testing is huge.

If I am positive yesterday. Is it the case of just waiting for PCR to come back?

I've felt off for a few days, my husband and kids all have covid but I'm still testing negative. He got a false negative yesterday before going back to getting positives, but all my tests have been negative.

@Yellowmellow2

Good to hear the PCR is negative. I wouldn’t have thought you need to do any more LF tests now? I think we all perhaps need to try and reduce our use of LF testing unless necessary. They are free to us, but the financial implications of all this testing is huge.

I totally see what you are saying but my DM and MIL are both very vulnerable, I actually care for my DM so on the off chance that It could be picking early infection up and the pcr didn’t pick it up a test before visiting my DM tomorrow (with also having cold symptoms) would do less harm than doing the one last test

Sorry meant to say would do more harm than doing one last test, if I was actually to have covid with pcr maybe not picking it up x

@Haffiana

Flowflex have a lot of false positive I would definitely try and get hope of orient genes.

No they don't.

Flowflex have a specificity of between 99% and 99.5%. They almost NEVER show a false positive.

Ooh you’ve missed an awful lot of threads about this!

Firstly, using your own stats, if 10m tests are done then 100,000 would be a false positive. Hardly ‘never.’

Secondly, the data are showing that FlowFlex is more likely than any other test to show a false positive. Research it!

My DH alone has had four false positives on these, so have countless others on MN.

Do you have reflux @ConcernedAuntie?

From:

www.gavi.org/vaccineswork/how-likely-positive-lateral-flow-test-covid-19-be-wrong

"In people who did not have COVID‐19, LFTs correctly ruled in infection in 99.5% of people with COVID-like symptoms, and 98.9% of those without them."

There is a huge issue with PCRs showing false negatives - particularly in the early days of infection. That is why so many people are getting a negative PCR after a positive LFT.

The current guidance is that a positive LFT means you have Covid IRRESPECTIVE of a follow up negative PCR.

www.gavi.org/vaccineswork/covid-why-are-people-testing-positive-lateral-flow-tests-then-negative-pcr

The issue of people showing a faint positive on LFTs for weeks at a time may mean that - exactly as people show positive on PCRs for up to 3 months after infection - they have virus lingering that can be picked up by a swab.

This may be because they have had an infection, or because they have been in contact but do not have a sufficient viral load to get infected, or some other reason.

Secondly, the data are showing that FlowFlex is more likely than any other test to show a false positive. Research it!

Please do share your data. How many percentage points exactly??

@LFTquestion

Do you have reflux *@ConcernedAuntie*?

Nope.

The issue of people showing a faint positive on LFTs for weeks at a time may mean that - exactly as people show positive on PCRs for up to 3 months after infection - they have virus lingering that can be picked up by a swab.

Wasn't it explained recently, because of the introduction of day 6/7 testing, that LFTs don't pick up infection in the medium term the way PCRs do; because they are an entirely different kind of test?

@Haffiana

The issue of people showing a faint positive on LFTs for weeks at a time may mean that - exactly as people show positive on PCRs for up to 3 months after infection - they have virus lingering that can be picked up by a swab.
This may be because they have had an infection, or because they have been in contact but do not have a sufficient viral load to get infected, or some other reason.

But this has been happening to me for SIX MONTHS. The only person I have been in contact with who subsequently had Covid was in October 2020.

So, if I do another test today and get the same positive result I isolate for 10 days. At the end of those 10 days I do another and get a positive I isolate for another 10 days and so it goes on. All this is assuming I don't have symptoms, of course, but then I never have.

@elelel

The issue of people showing a faint positive on LFTs for weeks at a time may mean that - exactly as people show positive on PCRs for up to 3 months after infection - they have virus lingering that can be picked up by a swab.

Wasn't it explained recently, because of the introduction of day 6/7 testing, that LFTs don't pick up infection in the medium term the way PCRs do; because they are an entirely different kind of test?

It remains an unexplained phenomenon. I cannot find anything that even suggests why this is. Anecdotally it is specific to certain people and it may or may not be due to virus.

[quote ConcernedAuntie]@Haffiana

The issue of people showing a faint positive on LFTs for weeks at a time may mean that - exactly as people show positive on PCRs for up to 3 months after infection - they have virus lingering that can be picked up by a swab.
This may be because they have had an infection, or because they have been in contact but do not have a sufficient viral load to get infected, or some other reason.

But this has been happening to me for SIX MONTHS. The only person I have been in contact with who subsequently had Covid was in October 2020.

So, if I do another test today and get the same positive result I isolate for 10 days. At the end of those 10 days I do another and get a positive I isolate for another 10 days and so it goes on. All this is assuming I don't have symptoms, of course, but then I never have.[/quote]
Yes, and you are not the only one, ConcernedAuntie. The one thing that is good about this epidemic is the extraordinary sharing of information by scientists and people interested in science, and the use of media such as forums and twitter etc etc.

The PCR lab testing fiasco last year was highlighted on SM first. Let's hope that this is getting picked up. I would love to know the reason just as much as you!

It remains an unexplained phenomenon. I cannot find anything that even suggests why this is. Anecdotally it is specific to certain people and it may or may not be due to virus.

What? That LFT and PCR are different tests? No that's not unexplained at all

@Haffiana

Yes, and you are not the only one, ConcernedAuntie. The one thing that is good about this epidemic is the extraordinary sharing of information by scientists and people interested in science, and the use of media such as forums and twitter etc etc

Right, OK, you do actually acknowledge that it does happen and those it happens to are not making it up.

So, who, in your experience, do I need to contact to registered this problem? Surely, the more people who are experiencing this report it, the more likely a solution will be found?

My GP and 119 were not interested.

Coincidentally I have had a phone conversation with a relative this morning whose 12 year old constantly tests positive on LFT. It is causing them no end of problems with them being able to go to school.

What would possibly get it flagged is to use the Zoe app and log every single positive LFT with them.

The current guidance is that a positive LFT means you have Covid IRRESPECTIVE of a follow up negative PCR.

Yep - and it’s going to cause absolute havoc for those employees who don’t actually have Covid yet who keep getting faint LFT lines:

www.mumsnet.com/Talk/coronavirus/4447414-Anyone-else-get-false-positive-LFTs-Worried-about-the-new-rules-impact-on-time-off-work?msgid=114042088#114042088

Sorry I forgot they had a 15-30 mom read time! I was just thinking of the old nose/throat ones. Flowflex have a lot of false positive I would definitely try and get hope of orient genes.

I've only used Flowflex and I've left it 15 minutes and then binned it. Should I be waiting longer?

@PinkSparklyPussyCat

Sorry I forgot they had a 15-30 mom read time! I was just thinking of the old nose/throat ones. Flowflex have a lot of false positive I would definitely try and get hope of orient genes.

I've only used Flowflex and I've left it 15 minutes and then binned it. Should I be waiting longer?

The instructions say 15-30 mins.

assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1030995/COVID-19-self-test-nose-only-instructions-acon-flowflex.pdf

Thanks @elelel. I presume if it's negative at 15 minutes it should be fine. I was worried I'd done something wrong!