Southland Hospital has temporarily closed its medical and surgical wards to visitors, after nine staff came down with gastroenteritis.
Te Whatu Ora/ Health New Zealand said barring visitors would protect patients and staff from the highly infectious illness.
The hospital does not know when the wards will be able to allow visitors again.
On Friday, there were 14 gastroenteritis cases in Southland hospital, with nine staff and five patients falling ill.
Te Whatu Ora said people who wanted to visit patients on compassionate grounds could discuss their situation with the nurse manager.