At a glance

More than 700 Aucklanders had their elective surgeries postponed in just four weeks as the city's hospitals struggle to cope with more patients flooding through their emergency departments.

Across Auckland City, Middlemore, Waitakere and North Shore hospitals, 320 more elective surgeries were postponed in a four-week period from mid-June to mid-July than during the same period last year.

The hospitals said it was largely because of unusually high numbers of acutely unwell people arriving at the hospitals. During the same period the four hospitals saw an extra 2336 people arrive in the emergency department compared to last year.

Last month all four hospitals asked people to stay away unless it was an emergency to help make sure those who really needed treatment could be seen to quickly.

Both Auckland City and Middlemore hospitals have seen record number of patients seeking care through their emergency departments this winter.

Auckland City Hospital director of adult medical services Barry Snow said in March the emergency department had seen a 7 per cent growth on last year while the inpatient unit was up 3 per cent.

"We are as busy as we've ever been," he said. "We've never treated so many people."

An Auckland DHB spokeswoman said the unprecedented numbers had led to an increase in the number of acute admissions so some elective surgeries had been postponed, she said.

The postponements would have an impact on some others waiting for treatment but staff were working to minimise the flow-on effect, she said.

The number of patients coming through the Auckland City emergency department in recent days had dropped but with August usually the busiest month for the city's hospitals, it was too early to say what was in store for the rest of winter.

Counties Manukau director of hospital services Phillip Balmer said every winter beds were reallocated between services to meet the heavier medical demand.

"This year demand has been much higher than anticipated and so meeting this demand has been challenging," he said.

During the four-week period there were an extra 147 people on the waiting list for acute procedures compared to last year.

Unusually, the number of people arriving at hospital with flu-like symptoms started earlier this year, he said.

A Waitemata DHB spokesperson said both North Shore and Waitakere hospitals had been seeing a high demand for emergency service, due to a wide range of medical presentations including winter illnesses.

Environmental Science and Research figures showed 188 people a week had been admitted to hospitals around the country and diagnosed with the flu since mid-June, roughly double what it was at the same time last year.

The highest flu rates this season had been recorded in Auckland, Waikato and Wellington.

The most prevalent strain of flu this year, Influenza A, was a particularly nasty one which made people much sicker, ESR public health physician Dr Jill Sherwood said.