The geriatric health ward, 6B, has been closed after three patients and one staff member became ill with vomiting and diarrhoea, symptoms of norovirus.
Otago District Health Board infection prevention and control charge nurse manager Jo Stodart said the ward was closed to visitors and admissions of patients.
"Closing Ward 6B could be being overcautious, but we are keen to contain the outbreak as quickly and effectively as possible, particularly with a long holiday weekend looming."
An outbreak in the orthopaedic ward, 3C, this week had been confirmed as norovirus.
The ward, which was closed on Monday, reopened yesterday, although two of the five patients who fell ill have been isolated as they have not been symptom-free for 48 hours.
During August, the hospital took drastic measures to control a month-long norovirus outbreak, postponing more than 2000 procedures and appointments and not allowing visitors into the hospital for a full week.
Almost 200 staff and patients fell ill then.
Ironically, this week is Infection Prevention Week and senior hospital staff learnt yesterday morning what was involved in a "terminal clean".
This is undertaken after a room has been used by a patient who has an infectious disease, such as norovirus, Methicillin-resistant Staphylococcus aureus and chickenpox.
An overpowering smell of bleach wafted out of room 27 in Ward 7C during the simulated exercise, as one manager used a special mop to clean the walls and ceilings and another used a small bottlebrush to scrub the wheel rims of a bed.
They emerged after 1 hours, sweaty, red-faced and gasping for fresh air as they peeled off gowns, gloves and masks.
ISS hospital services manager Heather Fleming said a terminal clean involved removing everything portable from the room, such as linen and curtains, for washing, and medical equipment for sterilising, as well as cleaning every surface, including mattresses, cup- boards and windows, with bleach.
Hospital cleaners usually did up to five terminal cleans every day and during the previous month-long norovirus outbreak they had clocked up 1400 hours of terminal cleaning.
It generally took four cleaners one hour to complete a terminal clean.
However, having a safe, clean hospital was everybody's responsibility, she said.
"Your clean room or clean stairwell is only as clean as the last person to put an infectious hand on it."
Mrs Stodart said the fact no cleaners fell ill with the highly infectious norovirus - which can survive for months on surfaces outside the body - during the previous outbreak was a testament to their strict infection control procedures.
