Does anyone else keep getting false positives on LFD tests?

[Boofay]

Hi. I have been doing regular LFD tests because of my job since March/April. Since then I have had at least four or five false positive tests. The most recent one was yesterday morning. Immediately booked a PCR test and a negative result came back last night.
I was under the impression that false positives are rare, but if that's the case, why have I had so many?
I follow the instructions carefully (been doing them for so long, I could probably do them with my eyes closed). I do them first thing in the morning before I've eaten or drunk anything, but if I do them later in the day, I make sure I do them after a long period of not eating/drinking.

Has anyone else had experience of this? Have you been able to work out why this happens?

I have the same thing and can't figure out why either

No, I know people who are getting negative PCRs which are false though (still). I’d do a postal PCR.

Are you one of the mythical superspreaders?

@Angrymum22

Are you one of the mythical superspreaders?

Had my first false positive back in June. Surely I can't have been positive four or five times since then? Test and Trace rang yesterday after I reported my positive LFD test and I spoke with her about the fear behind a false negative pcr. She spoke about the negligence at the PCR lab in Wolverhampton and that it has been closed down now. She explained the way pcr's are used to test for the virus. She said that if I get a negative pcr result, I am to trust it. All my positive LFD tests have been super faint, there's not been any strong lines. Also, no one has gone on to become positive after seeing me. Anyway, just looking for some answers.

DS had this happen twice (2 weeks apart in August). I suspect for him it might be to do with when he takes the test. Both the faint positives were done first thing in the morning, but he normally tests in the evening. I know acidic juice can make the line show, so I wonder if his mouth is acidic in the morning, possibly from sleeping with his mouth open? Just my own personal theory.

We just test in the evenings now just in case.

@Watsername

DS had this happen twice (2 weeks apart in August). I suspect for him it might be to do with when he takes the test. Both the faint positives were done first thing in the morning, but he normally tests in the evening. I know acidic juice can make the line show, so I wonder if his mouth is acidic in the morning, possibly from sleeping with his mouth open? Just my own personal theory.

We just test in the evenings now just in case.

Thanks for this. That's really interesting. All my faint positives have been from tests I've taken first thing in the morning. Maybe I am just an acidic person! 😂 I'll adopt evening testing like you and see how I get on. Thanks for responding!

I don't think it's acid, the liquid in the test is a buffer to neutralise the test, for that very reason. The way teenagers have been getting positive tests with orange juice etc is because they are dripping the acidic drink on the test on it's own, no buffer.
(no idea about the false positives though!)

The only slight link I've noticed is that it does seem to be when I've been exposed to the virus for a reasonable period of time. For instance, my children/friends etc. May just be coincidence though

Are you using the nose only LFTs?

Although the official line is that the lab problem is now over, some (including some scientists) are suggesting that it isn’t.

@Iggly

Are you using the nose only LFTs?

No, just the old style NHS box ones.

@JanglyBeads

Although the official line is that the lab problem is now over, some (including some scientists) are suggesting that it isn’t.

Thanks, @JanglyBeads. Do you have any links on this is could read?

I'm still staying away from people and have ordered an at home pcr test to double check.

Will Dr Amir on GMB do you?

twitter.com/dramirkhangp/status/1452584587255861250?s=21

Yes and I'm finding it really stressful. We have covid in our household. DS4 keeps getting very faint positive lateral flows but two pcrs have been negative. No symptoms at all but I just don't understand it. It is possible he doesn't have it because we have kept everyone well separated. But is it possible he does? Can the LTF be far more accurate than a PCR? We are isolating anyway but I want to know for number of days isolation etc.

My dh had a positive lateral flow followed by 2 negative pcrs. He was quite ill though and now has long covid, damaged lungs and possible heart issues. Totally recognise that his case is very rare though.

I would get the new style nose ones then and use those.

@Iggly

I would get the new style nose ones then and use those.

Easier said than done when the government ordering service keep sending me the old style, as do work. Any tips on getting the new style?

Yes! And I am using the new nose only ones!

It’s extremely frustrating me now as well @Satsunday DS & DH both have covid so I went for pcr on Sunday but felt well, no symptoms. Sunday evening started to feel really unwell with awful nausea. Did a lateral flow yesterday am which had a line although quite faint. Got the pcr result - negative. Felt worse as the day went on achey & nausea. Had another pcr last night which has just come back negative. 2nd lateral flow this am showed a line.
I’ve felt a bit better this afternoon but feel totally confused and don’t know what is going on. My poor dd 9 is the only one who hasn’t been poorly and is stuck inside for half term, all our plans cancelled. We’ve just been for a walk and talk and she was so sweet and said mummy I think you should ring the nhs and ask them what to do!

It’s just weird and sounds exactly like what was happening in the south west a few weeks ago but I thought that was all sorted. I just don’t get it.

@Iggly

I would get the new style nose ones then and use those.

I’ve been trying to get the new style ones. The pharmacy only have the old style so I ordered online. I have just had a box of the old style delivered.

Where are you getting the new style from?

We don't have any covid in the house, and this has been going on for a few months. I'm so confused.
Got a pcr test coming and will do it on Thursday.

@HazelandChacha mine came from the gov website

Yes my DH got a false pos yesterday followed by a clear neg. He was sloppy IMHO - didn't wash hands, moved it while it was developing but I think the real cause was putting in more than 2 drops, which he freely admits he probably did because the room was too dark. 2nd test done scrupulously carefully was a very clear neg.

I made a thread on it with a pic of the false pos if you want to compare.
www.mumsnet.com/Talk/coronavirus/4384579-Confirm-faint-positive-LF-please-Thanks

Where are you getting the new style from
Online ordering

The new ones are 4 drops & I think you sit the bud in the liquid for awhile as well.
More than 2 drops wouldn't do any harm, unlikely that moving it or not washing hands either.
The old ones will be fine with just nose too, as long as you have a good poke. There's no Magic that means it knows if you do both throat & nose.

[quote heldinadream]Yes my DH got a false pos yesterday followed by a clear neg. He was sloppy IMHO - didn't wash hands, moved it while it was developing but I think the real cause was putting in more than 2 drops, which he freely admits he probably did because the room was too dark. 2nd test done scrupulously carefully was a very clear neg.

I made a thread on it with a pic of the false pos if you want to compare.
www.mumsnet.com/Talk/coronavirus/4384579-Confirm-faint-positive-LF-please-Thanks[/quote]

Definitely not "sloppy" here, or doing it with unwashed hands. Only touch the stick end of the swab and the outside of the tube.
I don't think moving the test is going to effect it much. But I always leave it flat while it's doing it's thing. I swab my tonsils and my nostril.
Been doing these horrid things since March. I don't think there's any user error going on.