Public hospitals, GPs and the ambulance service are facing a major crisis as they are swamped by patients in what could be the worst flu season since the 2009 swine flu pandemic.
The number of confirmed cases of the flu has reached almost 1000 - three times the number at the same time last year - and doctors say many patients are more seriously ill than normally seen with the flu.
Disease experts are blaming the surge on one of this season's dominant viruses, influenza A/H3N2.
It is a potentially deadly strain which caused havoc during the last northern hemisphere winter.
The Australian Medical Association WA said there had been an alarming rise in flu cases across GP surgeries and hospitals in the past few weeks and the trend had worsened in the past few days.
Health Department figures show a 40 per cent rise (or an extra 11,000 patients) in emergency department attendances for the flu in May and June this year compared with the same period in the past two years.
Ambulances waiting to hand over their patients were forced to queue outside Perth emergency departments for almost 600 hours in the past 10 days, one of the worst ramping figures on record.
The blowout in patient numbers meant St John Ambulance failed to reach its crucial response time target for priority-one calls on Monday and Tuesday, managing to attend only 86 per cent within 15 minutes instead of 90 per cent.
AMA WA president Richard Choong said the flu crisis showed the health system did not have inbuilt "surge" capacity.
"We run all year at nearly 100 per cent capacity and we cannot cope with this seasonal load because there just doesn't seem to be the resources and beds to cope," he said.
Shadow health minister Roger Cook said ambulance ramping levels had hit a staggering 826 hours last month but in a little over a week this month they had reached almost 600 hours.
"The issue is getting beyond a joke and means a huge waste of resources at a time when we most need them," he said.
Health Minister Kim Hames put out a plea to patients with less serious flu-type illnesses not to go to hospital emergency departments and instead use their local doctor or after-hours GP clinics, which could be found using a smartphone application.
"We've got a big rise in the number of people with flu-like illnesses going to our hospitals, so if you have someone in your family who's seriously ill there's the risk hospitals will struggle to look after them," he said.
"Our ramping times are up but it's no wonder because we're seeing all these extra patients, so I would appeal to people to use other options wherever possible." He also called on GPs to keep their practices open later at night and at weekends to fit in more patients.
Dr Hames said from next week a trial would be introduced at Royal Perth Hospital, one of the worst affected recently by ambulance ramping, with 273 hours reported last month.
The trial would allow some ambulance officers to stay with low-level care patients waiting to be admitted to the emergency department, while allowing other officers to go on to other callouts.