Health authorities in NSW and Victoria are urgently trying to track down passengers on multiple flights from Iran to Australia who were sitting near passengers infected with coronavirus.

A woman in her 50s and a man in his 40s arrived in Sydney from Iran on separate flights last week.

Both are in hospital after presenting COVID-19 symptoms after arriving.

Meanwhile, a woman in her 30s has been confirmed as Victoria’s ninth coronavirus patient after arriving in Melbourne from Iran on Friday.

NSW authorities on alert

Passengers who arrived in Sydney on Qatar Airways flight QR908 on February 23 have been asked to be alert to symptoms of coronavirus.

Authorities are investigating exactly where a woman, aged in her 50s, was sitting on the aircraft.

On Monday, NSW chief health officer Dr Kerry Chant said those who sat a couple of rows in front of and behind the woman should self-isolate for 14 days.

People who sat near a woman who flew into Sydney with coronavirus are urged to stay at home. Credit: AAP

“We will be reaching out as soon as we’ve got contact details,” Chant told reporters in Sydney on Monday.

The woman is in hospital, as is a man in his 40s who arrived in Sydney from Iran on a separate flight on February 22.

It is believed he was not infectious during the flight.

“He did not develop symptoms until 24 February 2020 and was seen at a hospital emergency department and tested on 28 February,” Chant said on Sunday.

File image of a Qatar Airways Airbus. Credit: Getty Images

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“He was advised to be isolated at home while waiting for the test result which was confirmed positive for COVID-19 late on 29 February.”

Health Minister Brad Hazzard added two of his close contacts were in hospital quarantine and a further six were in self-isolation.

There have been six confirmed cases of coronavirus in NSW.

Tracking down Melbourne passengers

Meanwhile, authorities in Victoria are urgently trying to track down passengers on a Malindo Air flight which touched down in Melbourne on Friday after a woman travelling from Iran tested positive to the virus.

The state’s chief health officer, Brett Sutton, has urged anyone on Malindo Air flight OD177 from Kuala Lumpur to Denpasar then Melbourne, arriving at 6.04am on Friday, to contact the health department on 1800 657 398 for more information.

Chevron Right Icon ‘It’s unlikely that many people on that flight will be at risk.’

Passengers who sat in the same row as the woman, as well as two rows immediately in front and behind her, will need to be quarantined for 14 days.

“It’s really only very close contact for a relatively prolonged period of time that puts someone at risk and it was at the very beginning of this case’s illness,” he told reporters on Monday.

“It’s unlikely that many people on that flight will be at risk.”

FILE | Victoria's Chief Health Officer Dr Brett Sutton speaks to media during a press conference on February 27, 2020. Credit: JAMES ROSS / AAPIMAGE

Health Minister Jenny Mikakos said the woman became ill while returning home and was admitted to hospital on Saturday and put in isolation.

She then tested positive for the COVID-19 virus on Sunday.

The woman is now recovering at home, while another person who was in contact with her woman will be tested for the virus and forced to self-isolate at home for 14 days.

- With AAP