How reliable are lateral flow tests?

[Citycat1]

How effective are lateral flow tests? Me and my family have a nasty virus with some covid symptoms. (Fever, sore throat, phlegm producing cough) I have lateral flow tests at home. All are coming back negative. Anyone got them and had false negatives?

Hi as per my comment on the other thread -
If you have symptoms you MUST get a pcr not a LFT as they chemical makeup for testing is different. LFT is only for asymptomatic testing. Pcr for when you feel ill.

Get well soon. 🌸

But LFTs are for when you have no symptoms? You have symptoms so you need to take a PCR.

You need a PCR test and must isolate until you get s negative result.

LFTs are not for use when you have symptoms.

"You need a PCR test and must isolate until you get s negative result.

LFTs are not for use when you have symptoms."

^This.

LFTs are not designed to be used this way. You need to SI and get a PCR with symptoms even if your LFT is negative.

my daughter never tested positive on a lf, but she did on the pcr.

If you have symptoms you need a pcr.

You need a pcr test.

They are a complete waste of time
www.theguardian.com/world/2021/jun/11/us-health-agency-gives-innova-lateral-flow-covid-tests-scathing-review

My husband works for a school and is part of the covid testing team, they’ve done 8000 LFTs and not one positive…. Seems strange to me.

You need a PCR test when symptomatic.

LFTs have a very high false negative rate. That's OK for surveilling the asymtomatic population, because they are still finding a proportion of cases that would otherwise have gone undetected. But not when symptoms are present and you need a much more reliable test.

I know of 2 secondary children and a primary who were positive on LFT and negative on PCR. All recent.
I find that concerning.

Thanks everyone. Sorry to post this on somebody else thread too. I got muddled up! That would be sleep deprivation! Will get a PCR test today. I didn't realise the LF's were so crap. What's the point in them then? I have been isolating anyway but family are convinced it's not covid as we're all double vaccinated. I'm, however not so sure so will get a test today.

Good luck.
Hopefully just another virus. Know of a few people who have had a throaty thing but no temperature. [Negative LFTs].
It is perhaps the temperature that means the check is needed.

My friend and her husband have just tested positive- both are double vaccinated.

On a pcr laselvar?

the point of the lf's is for people with no symptoms. Picking up some cases in people who wouldn't normally test is better than picking up none of those cases.

If you have symptoms you are more likely to have covid so need the pcr.

@DinkyDaisy

I know of 2 secondary children and a primary who were positive on LFT and negative on PCR. All recent. I find that concerning.

Concerning in what way? We know that LFTs aren't 100% reliable that's why you take a PCR test to confirm

That's the system working properly

It's not been said that either test has 100% accuracy

@Orchidflower1

Hi as per my comment on the other thread - If you have symptoms you MUST get a pcr not a LFT as they chemical makeup for testing is different. LFT is only for asymptomatic testing. Pcr for when you feel ill.

Get well soon. 🌸

This! Really, how can people not know this!!

@DinkyDaisy

I know of 2 secondary children and a primary who were positive on LFT and negative on PCR. All recent. I find that concerning.

In what way is this ‘concerning’? This is the system working as it should. What is ‘concerning’ is that you don’t know that

*Concerning in what way? We know that LFTs aren't 100% reliable that's why you take a PCR test to confirm

That's the system working properly

It's not been said that either test has 100% accuracy*

Concerning in that others lives have to go on hold for no reason. I know from experience. You also get people who can't be arsed to do pcr [again experienced this] and who knows if they were a false positive or not? Were asymptematic and happy to have time off...

Not in the slightest, as is becoming clearer by the day with the U. S agencies now stating they should be binned.
We've spent millions of taxpayers money on them though and presumably have to use them all up trying to prove how desperately frightening all these awful variants are, or other such nonsense.
I have no idea why people insist on using them. They are worse than meaningless.

Not in the least reliable.

www.google.com/amp/s/amp.theguardian.com/world/2021/jun/11/us-health-agency-gives-innova-lateral-flow-covid-tests-scathing-review

I work in a small SEN school. We were all being tested at school in January. 12 out of 17 staff caught Covid and not one of us was picked up by the LFDs. It really worries me when you see how much people rely on these damn things.

Did any other country go for this type of mass screening with unreliable tests?

I know. So many people using them when they have symptoms. The message has really failed to get out there so that means they are probably doing more harm than good.

DinkyDaisy -* On a pcr laselvar?*

Yes. Husband got fever/ flu symptoms, both got PCR test, both positive. Wife also has flu like symptoms.
Husband had 2nd vaccination over a month ago, wife had only just had it. Both are poorly, but not worryingly so.