So if you’re positive you’re going to isolate for 10 days?
The guidance still says to isolate if you can, for at least 5 days.
And that if you have to go out, to practice social distancing.
Employers need to know so they they can, epwhere necessart, make arrangements to protect vulnerable co-workers, clients and service users.
And of course the person you pass it on to might become poorly enough to need time off and they might not be able to afford that either. So if your concern is to avoid the need to take time off work, the answer is to test and take precautions
No, it won't stop the spread in every case, but it will minimise it in many, and that is good