A NSW woman has tested positive to swine flu in Australia's first confirmed case of the illness. 
 

The woman flew into Brisbane from Los Angeles on flight QF16 on Thursday and tested "weak positive'' to the human swine influenza.

Experts say the woman is no longer infectious and had a weak strain of the virus, however passengers who were sitting close to her on the flight and her family members were being contacted by authorities.

Federal Health Minister Nicola Roxon said the woman, who cannot be identified for privacy reasons, contracted the disease in late April while overseas and had recovered before returning to Australia.

The woman identified herself to a nurse at Brisbane Airport, Ms Roxon said.

Results from the World Health Organisation (WHO) laboratory in Melbourne came back positive at 1am (AEST) today, she said.

"The strain of the flu has been identified in the sample but at a very low count," Ms Roxon said.

"This is clearly a serious development but we are in a situation where the best medical advice seems to indicate that this person wouldn't be infectious.

"This is a situation that we have constantly been advising the public was inevitable."

Queensland's chief health officer Dr Jeannette Young said the woman had tested "weak positive" to the human swine flu influenza.

The woman began experiencing symptoms while in the United States on April 27.

She was screened and swabbed at Brisbane Airport, given a mask and went to stay with her family, who live in Brisbane, while awaiting test results.

Queensland Health will contact the people sitting in the rows in front and behind the woman on the flight and will ask them whether they have any flu-like symptoms.

"Because we're taking every precaution, we will be contacting passengers from the same flight sitting close to the woman, and her close family, to check if they have had any illness and alert them to seek medical advice if they become unwell," Dr Young said.

"While advice from state and commonwealth experts is that other passengers are highly unlikely to become unwell because the woman was not infectious when she got on the flight, any other passenger on the flight with concerns can contact 13 HEALTH or visit their local GP."

Some 567 people have been tested for swine flu in Australia and 544 have been cleared.

Eighteen people are still awaiting test results.

Australia's chief medical officer Jim Bishop has advised Ms Roxon that Australia should not step up its swine flu response measures.

The WHO said overnight that 2500 people in 26 countries had tested positive for the influenza A (H1N1) virus.
AAP