False negative?

[namechange47582]

DD came down with cold symptoms last Thursday which had turned into a cough by Friday. I then started to come down with a cold/sore throat/cough. We obviously kept her off nursery and on the Saturday got us both tested. Both came back negative. I was planning to send her back into nursery as soon as her symptoms had gone. However it turns out a number of other children have all had similar symptoms and have tested positive so we have all been told to self isolate.

I'm now thinking surely we have had a false negative or it would be a strange coincidence for DD to catch a bug at the exact same time the other children caught COVID. Admittedly it was hard to do the test on DD so I thought it may come back inconclusive but I did it correctly on myself. Anyone any idea of the chance or false negative?

Quite likely in your kid - researchers have found the young children's immune systems can eradicate the virus VERY quickly - before they can test +ve which is why they frequently don't show symptoms.

In yourself - no idea - done by trained personnel, the rate of false negatives is miniscule, but they do occur.

I'd get yourself retested if you can, esp if the symptoms continue.

NB I assumed it was a PCR test you had.

LF tests FREQUENTLY show false -ves