Qantas officials have tracked down almost all 359 people who flew to Australia with a flight attendant thought to have Sars.
The airline would not say whether any flew on to New Zealand, but the Ministry of Health is confident it would have been notified.
The hostessmingled with 341 passengers and 18 crew for more than seven hours on Flight QF32 from Singapore to Sydney eight days ago.
Medical experts say the Sars virus can live for up to three hours outside the body. It can be transmitted by objects passed between people, such as food containers.
Qantas chief executive Geoff Dixon said the flight attendant, aged 25, was in Sydney's St Vincent's Hospital after becoming sick on Thursday.
He stressed that the woman showed no symptoms during the flight, and therefore was unlikely to have been infectious.
A Qantas spokeswoman said the airline started phoning the passengers on Saturday night, and had contacted 90 per cent of them by 5pm yesterday.
But the New Zealand director of public health, Colin Tukuitonga, said he would expect to have heard from his Australian counterparts if there was any risk.
"I'm quite confident that would have happened," he said.
A spokesman for St Vincent's Hospital, David Faktor, said the flight attendant had been isolated and her condition was stable.
The news came after New Zealand officials told people returning from Sars hotspots to delay surgery and avoid hospitals for two weeks.
Sars has dominated news so heavily in Western countries that it has buried reports of potentially the biggest outbreak of the deadly ebola virus.
The World Health Organisation believes the outbreak in the Democratic Republic of the Congo has almost been contained after killing more than 123 people.
The World Health Organisation lists 6054 people around the world as having Sars, with 417 deaths.
