Beaumont Hospital in Dublin has repeated a call to the public not to attend the emergency department if they have symptoms of the winter vomiting virus.
The hospital has already introduced visiting restrictions to wards. It said that people with symptoms, which include bouts of violent vomiting and diarrhoea, should contact their local GP or doctor on call service in the first instance if they have serious concerns.
Beaumont hospital spokesman
"People with these symptoms coming directly to the emergency department were causing needless cross infection of patients and staff there," a spokesman for the hospital said.
He said this had continued to put severe pressure on the department over the weekend and had "adverse knock-on effects for patients and staff throughout the hospital".
The spokesman said people should only visit the hospital wards if their visit really was essential.
"We don't want visitors picking this virus up and bringing it home for Christmas. And nor do we want more people bringing it in with them and adding to our difficulties."
Outpatient appointments are not affected by the restrictions but anyone who has had a stomach upset involving the symptoms of the virus is asked not visit the hospital for at least 48 hours after the last episode.