Positive PCR, yet to test positive on lateral flow on Day 5

[keepingfingerscrossed]

Just wondered if anyone has experienced anything similar? My husband tested positive on a lateral flow last Sunday so on Monday myself and my daughter went for a pcr. I only tested as I was taking my daughter who had symptoms whereas I didn’t have any and we had both obviously been in contact with my husband. My PCR test came back positive. Hers was negative. I’ve phoned track and trace and checked the bar codes didn’t get mixed up on our two tests but I have never tested positive on a lateral flow - not even a hint of a line and tomorrow is Day 6?! On day 0 and 1 I had unbelievably painful aching in my legs and felt under the weather so I do think I’ve had it but just can’t work out the testing. Has this happened to anyone else?

I know of people who've been really I'll with Covid and never had a positive lateral flow, yes.

Lft are crap. I tested on pcr (as daughter is positive) on Thursday result positive. I feel awful today done a lft not sure why but it was negative done a 2nd negative done a 3rd different brand negative again. I feel my worst today surely I can't be negative already on day 3 and feeling rubbish.

Thanks both - interesting to hear this is happening to others. It was starting to make me wonder if there had been a mix up at the man which I know is highly unlikely. It’s just very weird. W

*mix up at the lab

My son tested positive on LFT, daughter came down with same symptoms, so took her for PCR. PCR came back negative 48 hours later, despite her being quite poorly. She finally tested positive on LFT on day 4 of symptoms and didnt get a negative test until day 10. I have lost all confidence in both PCR and LFT tests now.

I had a positive PCR and never tested positive on LTF. I'm not convinced it wasn't a mix up. I isolated but still not sure I ever had it.

If you have Covid in the house and symptoms though then your pcr is probably right. Also more accurate than LTFs.

One point of note is they do have to be performed correctly.

Most of the time when you are taking the swabs yourself you do it nowhere near 'well' enough.

I have very recently realised Dh doesn't know where his tonsils are - so 2 years into covid, numerous lateral flow and PCR tests and it turns out he's been swabbing his tongue . There is no wonder all his tests have been negative.

It's not that weird really because everyone reacts to a virus differently. That's why some people end up being super spreaders and others might not infect anyone else in their house. The immune system is highly complex and there is never going to be 100% accuracy in measuring these things.

Broadly though, lateral flow tests are a pretty good indicator of how 'infectious' you are - though even that wanes with time. (Eg even if you're still testing postive after day 6, you're ability to infect others is smaller)

PCR tests look for the actual rDNA - so if you are at the beginning of an infection the virus may not have had enough time to replicate enough to be detected - or may not be in the place you are testing yet. So done early on, may not pick up the infection - despite having symptoms.

this is why lateral flows are so useful in stopping the spread.

Did you make sure that the test you did was the one preregistered to you, and the same for your DD? Any mix up is more likely to have been on your end rather than the lab side.

If you have tested positive on PCR, why are you even testing every day?

@kittensinthekitchen - yes I’ve checked they weren’t mixed up and took photos of each bar code for myself and my daughter which I doubled checked with track and trace. Plus my daughter has been testing negative subsequently too. We are still testing on lateral flows because I have two other children and so we have been checking daily due to a vulnerable family member. I’ve done mine at the same time out of interest because I was testing daily on lateral flows due to the vulnerable family member before the pcr test which were all negative up to the point of pcr. @tickingthebox73 I 💯 have done the test correctly. I’m really over cautious about this due to vulnerable family member. Ive been isolating from the family member as much as possible so it is causing things to be really difficult in the household at the moment.

On a separate note do people think if I test negative today it is okay for me to now go out 🤷‍♀️. As will have been clear on days 5 and 6?

I am responsible for showing people how to do LFTs at work. I know exactly how to do them and have helped my dc to do them regularly.

I had a positive PCR in Jan. I was v unwell with obvious classic Covid symptoms. I had no positive LFTs. Not one. I'd been doing them daily for work before falling ill and then on the days while I waited for the PCR. Tested on days 3, 4, 5, 6 and 7 and then again on day 10. Nothing. Not even a hint of a line.

Collegue at work a whole week of negative prior to having a pcr. Went for one as they had been in contact with 3 people who positive. Her PCR came back positive

@ShowOfHands thanks for commenting - really helpful to know this has happened to others. Did you go on days 5 and 6 (or whatever days you were free to go out again at the time) or did you wait the full ten days?

I was too ill to go out until well past 10 days of isolation.

Yeah this is common. I never tested positive on LFTs at all when I had Covid. I absolutely had it as I had cold symptoms, lost my smell and taste and had 2 separate positive PCRs.

www.gavi.org/vaccineswork/immune-covid-19-why-some-people-test-negative-when-everyone-around-them-testing

Have a look at this. Not testing correctly is possible but not the only explaination and if you are testing regularly is much less likely.

See explainations of rapid clearance, genetic resistance and viral load.

So yes it is 'a thing'.

(I've had twice instances with household cases and symptoms but coming up as negative on both ltfs and pcrs multiple times. And I know two other people who appear to have had the same problem).

@tickingthebox73

One point of note is they do have to be performed correctly.

Most of the time when you are taking the swabs yourself you do it nowhere near 'well' enough.

I have very recently realised Dh doesn't know where his tonsils are - so 2 years into covid, numerous lateral flow and PCR tests and it turns out he's been swabbing his tongue . There is no wonder all his tests have been negative.

My dd6 done one herself she skimmed her nostrils with the swab it certainly never went up her nose it came back positive.