"A lot of staff - nurses and doctors - are coming down sick as well."
Up to 15 per cent of staff were off sick at any one time, which was unusually high, even for winter, Dr Sullivan said. Senior management, including himself, were having to help fill some shifts at short notice.
He agreed the outbreaks were localised, saying the White Cross' Otahuhu and central Auckland clinics had not been affected.
He was uncertain why this was.
Christchurch virus expert Dr Lance Jennings said the outbreak of influenza in his city, dominated by the A (H3N2) strain, had also been localised at first, with after-hours clinics, the Christchurch Public Hospital's emergency department and some GPs seeing many influenza-like cases, while other GPs saw few.
The hospital had set up an influenza isolation ward and had cancelled elective surgery for a week, Dr Jennings said.
Spokeswomen for the Waitemata and Counties district health boards said yesterday their hospitals were running at capacity, but this was because of a variety of ailments.
"It is not because of influenza," Waitemata spokeswoman Ashley Campbell said of her board's hospitals. "It's the usual general mix of illnesses; just more of it than normal."
The state-funded influenza vaccination is available until July 31 for people with a specified range of health problems, those aged 65 or older and pregnant women.
Dr Jennings said the vaccination was up to 90 per cent effective in healthy adults of up to middle age, but less effective for the elderly, although it reduced the risk of complications such as pneumonia and death.
If you think you have influenza:
* Stay home and rest, away from other people.
* Sip fluids often.
* If you have an underlying medical condition, you are pregnant or your symptoms worsen, see your doctor or phone Healthline on 0800 611 116.
* Phone your doctor before visiting, if possible.
Influenza symptoms include:
* High fever
* Headache
* Chills
* Muscle aches
* Cough