Well, if you'd a dripping nose to the extent you can't do your job, you call in sick.
It's pretty common-sense, tbh.
There are a myriad of symptoms for Covid. Some people never have respiratory symptoms or a cough. Some people have no symptoms
However in order to have some way to manage resources effectively, they choose 3 most common symptoms. If you have one of them, get tested.
If not, and you feel well enough to go to work, do
If you worsen or feel more seriously unwell, seek further advice from your workplace.
It's not that hard.
Thank you for this very sensible response and the others also. They have partially restored my faith in nation's intelligence levels.
Almost every ailment you could imagine is on the longlist of symptoms - a line has to be drawn somewhere!