Public Health England is expected to advise that schools do not need to close or send staff and pupils home while tests are carried out on a suspected case of coronavirus.
If a case is confirmed, health protection teams will speak to the head teacher and action will be taken.
It comes a week after at least seven schools in Brighton, Hove and Eastbourne were understood to have told parents that either a staff member or pupil has been advised to stay at home for 14 days by PHE.
Schools messaged parents saying they would authorise absences for families wishing to self-isolate.
PHE is expected to issue the new guidance later.