The Lemon Fool

I had three very feint positive LFT results in a row. Followed up with a PCR test and the result was negative. I then had two more very feint positive daily LFT results in a row before finally being clear. No symptoms whatsoever. I've had two jabs and a booster a month previous.
Anyone else had anything else like that? Did i actually have covid???

Alan1701 wrote:I had three very feint positive LFT results in a row. Followed up with a PCR test and the result was negative. I then had two more very feint positive daily LFT results in a row before finally being clear. No symptoms whatsoever. I've had two jabs and a booster a month previous.
Anyone else had anything else like that? Did i actually have covid???

I've had nothing like that, but AIUI false positives with lateral flow tests are possible but extremely rare, which is why they are so useful. So five consecutive false positive LTFs seems impossibly unlikely to me as a layman. Did the "Control" line display clearly and correctly on each of the LFTs?

Far more likely that the PCR result was a false negative I'd suggest, but I know little about the PCR tests. Or about anything really!


(Edit to remove redundant word.)

yes the control line was clear and the positive results were very feint (needed to hold up to light otherwise would be missed).

i've done tons of these tests both for myself and work in the past so think i'm very thorough so nothing wrong with my testing technique i don't think.

The PCR tests are supposedly the gold standard and almost 100% accurate so more likely to think something amiss with the LFTs, maybe to do with omicron in some way not recognised yet but that's a wild guess. Not a faulty batch as partner did one and was clear negative.

Just wondered if anyone else had had anything similar.

My daughter felt she had cold symptoms starting 5 days ago and had daily negative LFT tests, then two days ago she had a very faint positive LFT, so she booked a PCR, which was positive. We aren't sure whether her symptoms of CV19 were the start of the "cold", in which case she doesn't have long left to isolate, but of course she may have unwittingly passed on the virus as she didn't isolate due to the negative LFTs. Alternatively the cold symptoms may have just been a cold and she caught CV19 seperately and had no symptoms. It's really difficult to know what to do, I suppose if in doubt isolate.

MM

Mike4 wrote:

Alan1701 wrote:I had three very feint positive LFT results in a row. Followed up with a PCR test and the result was negative. I then had two more very feint positive daily LFT results in a row before finally being clear. No symptoms whatsoever. I've had two jabs and a booster a month previous.
Anyone else had anything else like that? Did i actually have covid???

I've had nothing like that, but AIUI false positives with lateral flow tests are possible but extremely rare, which is why they are so useful. So five consecutive false positive LTFs seems impossibly unlikely to me as a layman.

Far more likely that the PCR result was a false negative I'd suggest, but I know little about the PCR tests. Or about anything really!

You are assuming that all false positives are independent. They might not be.

It is likely that all the positives have the same cause, but it might not be COVID. For example, Alan might have been infected by a rare, unrelated virus that has a weak cross-reaction to the LFT or all five tests might have come from a single rare bad batch. Five consecutive false positives might simply be "a bit more than extremely rare" rather than "impossibly unlikely".

None-the-less Mike's explanation would be my working hypothesis.