Two wards at Dunedin hospital are closed because of an outbreak of diarrhoea and vomiting among patients and staff.
The hospital is busier than usual, with a high number of acutely unwell patients. Some elective surgery has been postponed.
Southern District Health Board said on Wednesday it is closely monitoring the situation.
An outbreak of viral gastroenteritis has also closed the in-patient ward at Balclutha hospital.