So that's headache, sore throat, blocked or runny nose, cough, fever - cold symptoms.
Er, based on your preceding quote it's not!
You've listed those symptoms as if they correlate with the list, but they don't!
After headache it's loss of smell, then nasal obstruction, then a whole load more symptoms not associated with a cold at all, with sore throat coming towards the end.
It's really unlikely to be Covid with only common cold symptoms.
But they could be there as well.
Covid typically presents in a more flu-like way (it's not flu tho). Rapid onset, severe illness, exhaustion & temperature.
Not cold symptoms.
Of course, one can have Covid & have no symptoms at all, which is the problem.
But you can't provide testing in those circumstances.
So you develop reasonable criteria which don't fit every case of course but allow schools particularly to run as well as they can.
Physical distancing, hand hygiene & mask wearing go a long way to helping.
This silliness over # of coughs that make up a continuous cough is ridiculous & confusing & not used at all in Ireland.