A man who was turned away from a Queensland fever clinic because he didn't meet the criteria for COVID-19 testing has since been diagnosed with the virus in a private hospital.

Key points: Authorities are clearing coronavirus patients without issuing new tests to confirm they are negative

Authorities are clearing coronavirus patients without issuing new tests to confirm they are negative A man only found out he was positive after going in for elective surgery at a private hospital despite being refused a test at a fever clinic

A man only found out he was positive after going in for elective surgery at a private hospital despite being refused a test at a fever clinic Queensland health authorities maintain they followed the testing criteria

The man in his 60s was excluded from testing at the clinic in Brisbane last week because he had no contact with overseas travellers or confirmed cases, a Queensland Health source said.

But on Saturday he tested positive at St Vincent's Private Hospital in the city's north, where according to the source, surgeons wanted to check his symptoms before admitting him for unrelated elective surgery.

On Wednesday, Queensland Health's largest hospital service told staff it would broaden its testing to anyone suspected of having the virus.

Some clinicians said the case highlighted the weakness in Australia's response to the coronavirus outbreak before authorities pivoted to testing anyone with symptoms, in recognition of growing evidence the virus was spreading in the community beyond cases from overseas.

"It looks like it's about to break open — that's our prediction," a senior clinician in Metro North told the ABC.

However, authorities continue to clear COVID-19 patients without testing before allowing them out of isolation, despite the warnings of some experts that some people can remain infectious for up to three weeks.

Model wants proof she's no longer positive

Model Adelaide Sines is avoiding people until she actually returns a negative test despite being told she can. ( Supplied: Adelaide Sines )

Adelaide Sines, a fashion model who tested positive to COVID-19 last week upon her return to Brisbane from Europe, said she had been cleared to leave isolation today without a test to confirm she was no longer infectious.

But Ms Sines said she had pushed for a follow-up test and would continue to avoid people until she tested negative, out of concern that others could be exposed.

"Then I'd just know," she said.

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"It'd be a big relief off my shoulders and I would be able to go about seeing people in the community that are considered vulnerable — like my friend who had tuberculosis, like my grandma — and not have to worry at all and have that hanging over my head."

In an email on Wednesday, Metro North told staff with symptoms — regardless of any contact with COVID-19 patients — they should "promptly present to one of our fever clinics or to your usual healthcare provider … for assessment".

Staff were told the testing criteria had been changed to "fever of 38 degrees or higher OR a history of fever (e.g. night sweats, chills) OR acute respiratory infection (e.g. cough, shortness of breath, sore throat)".

It said that there had been an "update to national guidelines for COVID-19 case definition" on Tuesday night.

Last week the ABC revealed that Metro North, which is Australia's largest hospital service, catering for almost a million people in Brisbane's north, had repeatedly tightened its testing threshold amid a shortage of kits, reagents and personal protective equipment for healthcare workers.

Until midday on Wednesday, Metro North specified testing only for overseas travellers with fever and other symptoms, those in close contact with COVID-19 cases, and those with severe pneumonia.

Queensland COVID-19 snapshot: Confirmed cases so far: 1,153

Confirmed cases so far: 1,153 Deaths: 6

Deaths: 6 Tests conducted: 1,067,786

Tests conducted: 1,067,786 Active cases: 16 Latest information from Queensland Health.

This ruled out people including healthcare workers who had been in casual contact (less than 15 minutes) with COVID-19 cases or who had symptoms alone.

A spokesman for St Vincent's Private Hospital told the ABC it "had a patient present on Saturday night who tested positive for COVID-19".

"He was discharged from the hospital yesterday and is in home isolation," the spokesman said.

In line with federal policy

A Queensland Health spokeswoman told the ABC that all its hospital services were "working alongside and in-line with " state and federal health departments in response to the pandemic.

"Queensland Health's testing criteria, consistent with that outlined by the Federal Government, is designed to ensure the majority of cases of COVID-19 are detected quickly and efficiently," she said.

Who should present to COVID-19 clinics? People with a fever (or history of fever) or acute respiratory symptoms, AND , in the last 14 days:

People with , in the last 14 days: they were a close contact or a household contact of a confirmed case,

they were a they had been overseas, including on a cruise Testing is also possible for people who have a fever (or history of fever) or acute respiratory symptoms, AND: live or work in a high-risk setting such as healthcare, aged or residential care, military, correction facilities, detention centres and boarding schools

such as healthcare, aged or residential care, military, correction facilities, detention centres and boarding schools work in a school or child care setting or are a Queensland police officer

or are a live in Brisbane, Gold Coast or Cairns - Brisbane includes the Metro North and Metro South Hospital and Health Services

live in - Brisbane includes the Metro North and Metro South Hospital and Health Services live in or travelled from a COVID-19 hotspot

live in or travelled from a live in or travelled from another state

live in or travelled live in a First Nations community Queensland Health has set up testing and fever clinics for people who may be infected with COVID-19. Patients who are tested should remain isolated at home until they receive their test results. For more information about coronavirus call 13HEALTH (13 43 25 84) or go to the Queensland Health website

"This is critical in responding to an epidemic like COVID-19.

"The right way to do that is by ensuring that we are triaging correctly, and not testing people who are most likely to have other viruses, such as influenza or the common cold.

"Widespread public screening is not necessary. At this point in Queensland, the majority of cases are still from people who have travelled overseas, or have had direct contact with a confirmed case in someone that has travelled overseas.

"The criteria, like our national and international response, must change as our situation changes."

Prominent Australian immunologist John Dwyer and experts from the Centres for Disease Control and Prevention in the US have called for testing of people before they are cleared to return to work.

Prime Minister Scott Morrison on Tuesday night said Australia had "one of the highest testing rates in the world" with 147,000 already screened.

"We have been able to secure supply of hundreds of thousands of more tests into Australia," he said.

"Testing is critical to how we manage the coronavirus and its impact."