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AIBU?

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Original poster

To want the NHS or FlowFlex to research why all my LFTs are positive?!

110 replies

LindaBlinda · 01/12/2021 22:11

Because seriously I'm worried that maybe eventually I'll try to travel and it'll be a FlowFlex test and I'll be told I'm positive.

Every single FlowFlex test I take is faintly positive. Pink line. Within the 15 minutes. As the attached photo. The same for the last 3-4 months or however long ago the FlowFlex started being the ones the NHS mailed out.

Any other brand of LFT is 100% negative. If anyone else in my family uses the FlowFlex from the same boxes they get negatives.

I'm mid 30s and double jabbed with Pfizer. I've never knowingly had Covid. And have tested at least twice a week since we were able to have LFTs due to caring for a terminally ill family member.

When the rest of my household were recently infected with Covid I was the only one not to catch it. Luckily I have some boxes of the other LFTs and have in the past month had 3 PCRs as each other household member tested positive. Also had 2 PCRs the past 2 months due to these faint FlowFlex lines.

All been negative.

Please if anyone knows how I can get some information on this or get some advice about it I'd be grateful. As I don't want false positives (which everyone says are totally rare and impossible) to ruin any future freedoms.

If there are trials or something for people in the same boat I'd be very willing to take part. Just want to get to the bottom of it as I'm on my last box of non FlowFlex!

To want the NHS or FlowFlex to research why all my LFTs are positive?!
OP posts:
INeedNewShoes · 02/12/2021 12:56

Does anyone know if it's still possible to get hold of the other type of LFT?

I really want to stop using these crappy flowflex ones.

my8thMNusername · 02/12/2021 13:03

@googlage

My PCR has come back negative.

So both of yesterday’s positive FlowFlex lateral flow tests were false positives…!

Good news!
BudgeSquare · 02/12/2021 13:56

@INeedNewShoes

Does anyone know if it's still possible to get hold of the other type of LFT?

I really want to stop using these crappy flowflex ones.

Me too. There's covid in my kids' school classes at the moment and I can't use tests that are totally unreliable
simpledeer · 02/12/2021 14:16

YANBU

I have never heard of anyone getting a positive LFT in RL!!! Even when she had full on covid and positive PCR, my mate was still getting negative LFTs.

I don't believe they work at all.

MorningStarling · 02/12/2021 14:23

It just sounds like either you've had Covid and the tests were correct most of the time, or it's just a statistical cluster which sometimes happens with freak events despite their low probability.

If the tests were 99% accurate then once in a hundred times it would give the wrong result. Once in ten thousand times you'd get two incorrect tests in a row, and once in a million times you'd get three incorrect tests in a row. The probability of continued incorrect results never reaches zero, if enough people do enough tests eventually someone will have 100 incorrect results in a row.

The important point about this is to understand that we don't need to wait until the time comes for someone to have a 100 incorrect results in a row to be a likely event. It could literally happen with the first person who takes a hundred tests.

Iggly · 02/12/2021 16:09

@MorningStarling

It just sounds like either you've had Covid and the tests were correct most of the time, or it's just a statistical cluster which sometimes happens with freak events despite their low probability.

If the tests were 99% accurate then once in a hundred times it would give the wrong result. Once in ten thousand times you'd get two incorrect tests in a row, and once in a million times you'd get three incorrect tests in a row. The probability of continued incorrect results never reaches zero, if enough people do enough tests eventually someone will have 100 incorrect results in a row.

The important point about this is to understand that we don't need to wait until the time comes for someone to have a 100 incorrect results in a row to be a likely event. It could literally happen with the first person who takes a hundred tests.

It happened to dd twice in the space of about 6 weeks. She had 6 PCRs all negative, to check the LFTs. They weren’t strong positives but they were clearly visible and she was unwell which is what prompted me to do them. So something was clearly going on.

It’s a bit disconcerting that I can’t get an official answer to why this might happen.

Original poster
LindaBlinda · 02/12/2021 19:07

@MorningStarling

It just sounds like either you've had Covid and the tests were correct most of the time, or it's just a statistical cluster which sometimes happens with freak events despite their low probability.

If the tests were 99% accurate then once in a hundred times it would give the wrong result. Once in ten thousand times you'd get two incorrect tests in a row, and once in a million times you'd get three incorrect tests in a row. The probability of continued incorrect results never reaches zero, if enough people do enough tests eventually someone will have 100 incorrect results in a row.

The important point about this is to understand that we don't need to wait until the time comes for someone to have a 100 incorrect results in a row to be a likely event. It could literally happen with the first person who takes a hundred tests.

It doesn't take much to realise though that clearly these tests aren't 100% accurate.

Every. Single. One. I've done for months has been positive.

Yet every single other brand LFT and every PCR has been negative.

So that's a 100% discrepancy between FlowFlex and every other test.

So clearly there's something that isn't 99% accurate somewhere. Hence this thread and the frustration that myself and others who've had the same are feeling.

OP posts:
Tr1skel1on · 02/12/2021 22:06

Having had 2 +ve flow flex tests yesterday, negative PCR result just in.

I had Covid back in July, I know how it feels and what a +ve test looks like. I was fairly certain I didn't have it.

I'm just relieved. Dd1 has her mock GCSEs next week, I can continue focussing on that

SusannahHolmes · 05/12/2021 21:23

Interesting thread. Dd has just done her first ever flowflex and it's positive. She had covid in July so was a bit surprised and we immediately did one of our remaining old style tests, it's completely negative (see image). Not sure what to do now. She has no symptoms at all.

To want the NHS or FlowFlex to research why all my LFTs are positive?!
Dimondsareforever · 05/12/2021 22:13

As per other posters - I suspect you have had it. Dd who had Covid more than 3 months ago gets them. After a few episodes of SI for 2 days (and missing school) for just another negative PCR … I’ve given up testing her regularly. Will just do the rest of the house and only test her should she show any symptoms.

my8thMNusername · 05/12/2021 22:22

@SusannahHolmes

Interesting thread. Dd has just done her first ever flowflex and it's positive. She had covid in July so was a bit surprised and we immediately did one of our remaining old style tests, it's completely negative (see image). Not sure what to do now. She has no symptoms at all.
I'm sure you've already booked in for a pcr but that's the best step. Has she any known close contacts?

I don't trust the LFTs anymore - I got a couple of faint lines in the same week, results from PCRs which I did (both times - 3 days apart) within 2 hours of the LFTs came back negative. Another 4 days later I did another PCR - also negative.

I did have some negative LFTs too (I tested a LOT).

arci84 · 08/12/2021 14:07

I hope you don't mind me jumping in.

My wife tested positive-ish the first time in these FlowFlex tests back in November after we came back from Italy (it was a day-2 test).
After the initial panic (her mother is ill and we were doing our best to protect her), we booked a PCR test for her (since it was a day-2 test, we couldn't go to a test site).

Long story short, ALL FlowFlex tests still show slightly positive (but are considered fully positive if you're taking a pre-departure test), the classic, blue ones all negative, and PCR always negative.

I must add that she's been part of a government scheme where she was regularly tested for Covid antibodies (never detected), so the only explanation is that these FlowFlex tests are highly unreliable, which is a shame because it means that we have to pay for the more expensive PCR tests before going anywhere.

JaninaDuszejko · 08/12/2021 14:25

You should report it to the MHRA using the yellowcard scheme. The LFTs are considered a medical device. I would encourage everyone who has had this issue to report it to the MHRA using this process.

Birthdayhat · 08/12/2021 14:37

I'm having the same although not every test I take, several negative PCRs - at the moment it doesn't bother me too much but I am also worrying about future travel/events etc. I actually did email the Zoe study people and they said that as they're a small team they can't look into individual cases but would investigate - I imagine the more contact they get about it the more it would help the investigation?

Birthdayhat · 08/12/2021 14:38

Surely there must be some government data about how many people report a positive lateral flow and then receive a negative PCR?

googlage · 15/12/2021 08:26

Checking in to mention yet another false positive FlowFlex test in this house. Hmm

my8thMNusername · 15/12/2021 20:52

@googlage

Checking in to mention yet another false positive FlowFlex test in this house. Hmm
Did you do more LFTs and get a different result?

I had another positive first thing this morning. Subsequent tests were clearly negative (one done just 30 mins later). Flowflex again.

Now awaiting PCR results, ffs. Went though this a month ago!!

my8thMNusername · 15/12/2021 20:53

Oh and I also did one LFT from a different brand and it, again, was a stark negative

Honestly my mental health can't take much more of this.

JaninaDuszejko · 16/12/2021 13:40

@JaninaDuszejko

You should report it to the MHRA using the yellowcard scheme. The LFTs are considered a medical device. I would encourage everyone who has had this issue to report it to the MHRA using this process.
I'm just posting this again. Please please report this to the MHRC, they are the people responsible for monitoring these issues, not the Zoe app people.
my8thMNusername · 16/12/2021 21:23

Negative PCR in this morning ...

my8thMNusername · 16/12/2021 21:30

@JaninaDuszejko reported!

MolkosTeenageAngst · 16/12/2021 22:09

This sounds such a pain and reinforces my decision not to take LFTs, I know so many people who have had positive LFTs but then had negative PCR tests and it seems an unnecessary faff and source of anxiety to have to go through the isolating and waiting to find out the result. Clearly there is something wrong with some batches or brands of LFT, in your shoes I think I would just stop taking them.

Turniptracker · 16/12/2021 22:13

Haven't read the whole thread but I know some ppl with rheumatoid arthritis or other autoimmune issues find they constantly test positive on lfts so could it be that?

my8thMNusername · 16/12/2021 23:28

@Turniptracker

Haven't read the whole thread but I know some ppl with rheumatoid arthritis or other autoimmune issues find they constantly test positive on lfts so could it be that?
Spoke to GP yesterday with a concern that something else could be wrong but she says no that won't be it. I think LFTs are too new to say either way really.

It's ONLY happened very first thing in the morning, within 15-30 mins of waking up. Isn't that just really odd?!

shreddednips · 17/12/2021 00:12

Glad I found this thread! Same issue, but only first thing in the morning. It's been an absolute nightmare having to isolate to get PCRs. I contacted test and trace and they told me it's a known issue that's being investigated. I have no idea if that's true, but it if is they should distribute another brand and tell people to use them instead!

I've reported it under the yellow card scheme, thanks for signposting that.