I know a pcr can stay positive for weeks, but what about lateral flow?

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How quickly will it go back to negative, anyone know?

Anyone?

I thought it was advised 90 days

Really? What about pre departure tests for travel though- you can't be expected to stay abroad for 90 days?

We tested on hub, lft got stronger and then faded by day 10 clear

My DD’s flowflex has been positive for 6 weeks now (negative PCR).

Lateral flow went to negative by day 10. PCR however is still positive after 9 weeks!

I never had a positive LFT - even on the day I took a PCR that came back positive 🤣

My lft was negative again before my isolation was up.
I had an extremely clear positive result at first.

I work in the NHS and our staff who had a positive PCR are advised not to do LFTs for 90 days due to getting ongoing positives. If you need a PCR to travel I believe you can get some sort of medical certificate to prove you’ve had a positive PCR/Covid that means you’re exempt from testing.

It’s the PCR that can stay positive for up to 90 days, LFT should be negative after your isolation period

My dd had covid and we tired lat flow about a month after and it was negative

My kids lateral flows were completely negative by about day 6/7, but mine was not completely negative until about day 12

I'm day 14 today and my lft was positive yesterday but negative today. My symptoms seem to have disappeared overnight too thankfully.

My ds tested negative on a LFT after 7 days (that was the first day we re-tested so it might of been earlier, he only had one day of symptoms).
I understood that LFTs only show as positive when you are infectious, whereas PCRs can pick up fragments of the virus for much longer.

DH did an LFT 7 weeks after isolation ended and got a faint positive (no symptoms or anything, he was just 'curious'). Mine was negative however.

@mightyducks

It’s the PCR that can stay positive for up to 90 days, LFT should be negative after your isolation period

This isn't true - you're not supposed to test on LFT or PCR for 90 days after isolation ends due to the likelihood of a false positive (unless you have new symptoms).

It is true, having sat in many meetings about it, the reason they tell you not to LFD test for 90 days is because the PCR could still stay positive, for up to 90 days , therefore you’d never know if the LFD was a false positive , as you can’t clarify with a ‘true’ PCR test. The PCR can pick up fragments of left over viral RNA, LFD’s don’t , they detect proteins instead, showing whether you are infectious or not. There is also an assumed natural immunity for 90 days after a covid infection, so for this reason too, testing is not advised within 90 days.

So what happens if you take a predeparture test that's positive, how/when can you travel back if you potentially can't provide a negative test for a while?

Would love to know this too! We have flights booked to France for Christmas but looking less and less likely as DS school has more and more cases!

My son has a letter from his gp with dates of infection by Covid. It cost £30.

DD was clear on day 11 on LFT. We didnt think to check earlier.

@ThePontiacBandit

I work in the NHS and our staff who had a positive PCR are advised not to do LFTs for 90 days due to getting ongoing positives. If you need a PCR to travel I believe you can get some sort of medical certificate to prove you’ve had a positive PCR/Covid that means you’re exempt from testing.

I don't believe the UK accept a letter for return travel, it can work for things like theatre and venues domestically though.

When we flew to the US this summer, I'm pretty sure there was the option to take either PCR, LFT OR an antibody test to show that you had covid in the last 6 months. Best to look on the gov website and website of the government of the country you are travelling to.

My DD is on her last day of isolation today and decided to test her out of curiosity because she's due back at school tomorrow, she's tested negative on LFT.