"The Google flu tracker suggests nationally we have got activity approaching one of the higher seasons." Google produces day-by-day flu activity estimates for New Zealand and more than 20 other countries, based on rates of internet searches related to flu or influenza.
A research letter on the internet flu tracker in the scientific journal Nature, written by officials from Google and the US Centres for Disease Control and Prevention, says there is a close correlation between the rates of doctor visits for flu symptoms, and the use of flu-like search terms.
The New Zealand Government has extended free flu vaccination for the elderly and others at increased risk of serious flu complications by one month, until August 31, in anticipation of a delayed flu season.
Laboratories report that influenza A (H1N1) - the strain which caused the pandemic in 2009 and 2010 - is the main virus causing flu sickness across the country this year.
A patient with this strain died last week at Middlemore Hospital's intensive care unit, said Dr David Galler. Two others in the unit also had the pandemic strain and a third had a different flu virus. The two women with the pandemic strain were previously healthy. One is in her 40s and has been in the ICU for two weeks, and the other is 19 and has been there for a month.
"It's still a very dangerous disease for people, most dangerous for those with risk factors, but young people too," Dr Galler said. "You can get a devastating illness in previously healthy people. The message is to get vaccinated. It's crazy not to."
Dr Galler said the lungs of flu patients could develop an infection with staphylococcus aureus bacteria. A severe case of influenza could cause long-term lung damage and patients "may never be 100 per cent".
West Auckland patient Sharyn Huirama was booked for major surgery at North Shore Hospital yesterday, but was told by a booking clerk on Monday that her operation had been delayed until August 19, because an influx of patients had caused a bed shortage.
The delay was stressful and had thrown her life into disarray, said Ms Huirama, 45, although hospital staff had been sensitive and apologetic.
The treasurer of a charitable organisation, she had taken six weeks off work, which could be re-arranged, and her mother and aunt had travelled from Hawkes Bay to support her after the operation.
She is among 24 North Shore Hospital patients since Monday last week to have their elective surgery postponed by the winter surge.
"We've been operating at or near 100 per cent capacity for the last 10 days," said Waitemata District Health Board chief executive Dale Bramley.
North Shore and Waitakere hospitals' emergency department patient numbers were up, and medical admissions were up 20 per cent on this time last year.
"Unfortunately, in situations like this, we have to make urgent and acute cases our top priority," Dr Bramley said.
Auckland City Hospital said its occupancy had been high, emergency department attendances were up 5 per cent on last year, and many staff had been off sick, but it had not postponed any elective surgery because of the winter workload.
A spokeswoman for Middlemore said its medical wards were "pretty full" but no elective surgery had been cancelled.
A spokeswoman for Waikato Hospital said it was very busy, with staff sickness a problem, but it was not at present cancelling any elective surgery due to influxes of acutely sick patients.
How to avoid influenza spreading
• Have the flu vaccine
• Wash and dry hands often
• Stay away from people who are sick
• Stay away from work or school if unwell
• Cover coughs and sneezes
Influenza symptoms
• Sudden onset
• Fever of 38C or higher
• Headache
• Cough
• Muscle aches
Cold symptoms
• Mild fever
• Mild headache
• Congested sinuses, runny nose
• Sometimes a cough
