How accurate are LFTs when you have symptoms?

[SuperMonkeys]

Sister and I both take LFTs twice weekly for work. Sister took hers this morning and it was negative. During the day she has developed a cough.

Is it in any way likely that this is covid given that she had a negative test this morning?

It’s possible. That’s why they say don’t use LFT if symptomatic, so you don’t get a false negative then, thinking you are okay, go around spreading Covid. She needs to book a PCR test.

Yes, it could be COVID. I know someone for whom that was the exact pattern. The cough when it developed was not continuous by any means but they isolated and ordered a PCR test to be on the safe side, not expecting it to be be positive at all. And it was. And then went round the whole household.

She's ordered a postal test anyway, which is the right thing to do. I was just pondering what the difference between the tests actually was, it must be the processing as the actual sample collection is the same.🤔

I think they’re accurate, it’s more that they can give false negatives so they don’t want you thinking you’re ok if you’re not and going out spreading Covid.

LFTs are as accurate when you have symptoms as when you don't.

However they are far less sensitive than PCR tests, so more likely to give false negatives. This is why you can't rely on a negative result if you are symptomatic.

Funny isn't it, you'd hope they'd be more sensitive, given they're aimed at picking up asymptomatic cases who may well be carrying a lower viral load.

DS plays sport and is tested every day before training. He tested negative 3 times in the 5 days before a positive lft. Symptoms started same day as 3rd negative lft, so I'd yes yes!

He only had it quite mild though. Other cases suggest he caught it one weekend and tested positive the following Friday.

Interestingly his car sharer (lots of hours in car together) never caught it and no-one else in the team he trains with either 🤷‍♀️ (and neither did I even though i had to isolate with 2 positive cases).

After catching covid, you reach a point where there's sufficient virus to test positive, so yes you can be negative at 9am and positive at 5pm. It's why testing (pcr or lateral flow) makes little sense for overseas travel really except perhaps for a short plane journey, you could be positive by the time you get off. They make more sense for shorter things like a concert or football match.

My friend had two negative lateral flow tests either side of a positive pcr test - she had been vaccinated so wonder if she had a lower dose of covid ???either way it shows you can't rely on ltfs

Dd1 was in self isolation due to close contact. Her close contact was picked up during the 2 weeks of in school lf's. She had one the same day and tested negative.

She them continued lfs during self isolation all negative. Then she started coughing. Took a lf at home just before the pcr, negative, all good keep taking your inhaler probably asthma playing up. Pcr was positvive.

Dc housemates all had positive pcr - lft positive couple of days later for all of them so less sensitive I’d say.