Visiting restrictions have been extended at Beaumont Hospital in Dublin, following a outbreak of the winter vomiting bug.
Management is asking the public not to visit a patient in the hospital - unless that patient is critically ill. Children are not permitted to visit in any circumstances.
It's hoped a visiting ban will prevent others from contracting norovirus.
Essential visits and visits to those who are critically ill may only take place between 2 pm and 4 pm and between 6 pm and 8 pm, with only one visitor allowed per patient.