Wards nine, 20 and Grainagh Court remain closed at Noble’s Hospital following yesterday’s outbreak of norovirus among staff and patients.
The hospital urgently closed the three wards to new admissions just after 4pm yesterday.
Norovirus causes symptoms similar to severe cases of food poisoning and is highly contagious.
Both the hospital and the Mental Health Service say alternative care has been arranged so no patient’s treatment will be affected.
The hospital says the wards will remain closed for at least 72 hours once they are clear of the virus.