More than fifty patients and staff have become ill with the winter vomiting bug at the Dumfries and Galloway Royal Infirmary.
Three wards remain closed, after the outbreak was confirmed on Friday.
Infection control procedures are in place.
Visitors are being asked to stay away, if they have any symptoms.
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Calmer conditions - for now.
The 12.5 hour walkout by 63 GMB members got under way at 6am this morning and will continue until 6.30pm this evening.
37-year-old Graeme Haddon pleaded guilty to the offence which happened in his home village of Lamancha near West Linton at the weekend.