The orthopaedic ward at Taranaki Base Hospital in New Plymouth is in lock-down following a stomach bug outbreak.
Some surgery may be delayed.
Six patients have been affected by gastroenteritis since Monday: two have been sent home and four remain in isolation in ward four with about 20 non-infected patients.
Only hospital personnel and essential visitors wearing protective clothing are allowed into the ward. Discharges to rest homes and transfers to other wards or hospitals have been stopped.
Taranaki medical officer of health Dr Penny Hutchinson says laboratory tests should determine the cause of the vomiting and diarrhoea within a week.
She says ward four will stay locked-down for at least three days.
