Previously, the advice was that the parents of children told to give them Tamiflu but refused should keep their children out of school for seven days whether they showed symptoms or not.
But the Education department is now warning that if healthy children are absent from school, this will be marked as unauthorised absence.
Previous advice that allowed children to stay at home for a week if they did or did not take the drug stays in place for those who were issued Tamiflu between last Friday and Tuesday. They can do school work at home.