Nine more people at Waterford Regional Hospital are thought to have contracted the Winter Vomiting Virus.
Six patients and three members of staff have come down with the virus, also known as the Small Round Structured Virus.
On Monday, the South Eastern Health Board cancelled all non-urgent elective admissions to Waterford Regional Hospital following the discovery of suspected cases of the virus.
Overall, 25 patients and nine members of staff have reported symptoms consistent with the virus. Of these, 12 patients have recovered.
Tests have been carried out and the seven patients, who still have symptoms consistent with the virus, have been placed in isolated areas.
The hospital has been closed to visitors, apart from exceptional circumstances, and security staff are in place at the entrances to the hospital.
All outpatient clinic appointments, including fracture clinic appointments, are proceeding as normal, however. According to the health board, arrangements will be reviewed daily.
The South Eastern Health Board is appealing to members of the public to co-operate with these interim arrangements and to stay away from the hospital.