NSW Health authorities have worked through the night to contact passengers who were allowed to disembark a Melbourne-to-Sydney flight without a second health screening, the evening before the NSW-Victoria border closed.
"There was an issue at the airport where passengers were disembarked when the health screening team were screening another airline," NSW chief health officer Dr Kerry Chant said on Wednesday.
A NSW Health spokesperson later said airline staff hadn't followed the agreed protocols when they let passengers from Jetstar flight JQ520 leave the gate area before health staff had finished screening an earlier flight.
"As a result of this breach, flights will now not be allowed to land in NSW until NSW Health teams are in place to screen them," the spokesperson said in a statement.
A Jetstar spokesman told AAP on Wednesday the airline assisted NSW Health in finding most passengers before they left the terminal.
The airline also provided health authorities with the aircraft manifest in order to contact any passengers who left without a Sydney screening.
Temperature and ID checks had been undertaken by Victoria Health before the flight, Jetstar said.
"Together with Sydney Airport, we have refined our disembarkation procedures to prevent this situation occurring again," the spokesman said.
All passengers who disembarked the flight should be in 14 days of self-isolation as part of NSW coronavirus protocols.
"If anyone's travelled in breach of orders, we'll refer them to police and take the appropriate action depending (on) if anyone is symptomatic," Dr Chant said.
NSW Health also said the passengers had been screened before leaving Victoria.
Of the 137 who disembarked in Sydney, 89 were screened and cleared before leaving the airport, according to NSW Health.
Health officials contacted the remaining 48 passengers, with arrangements since made to screen 45.
The three remaining passengers - including one who has refused to be screened - have been referred to NSW Police.
NSW Greens MP Cate Faehrmann called on NSW Health Minister Brad Hazzard to investigate the incident after he made earlier assurances all passengers arriving from Victoria would be screened at Sydney Airport.
"It's gobsmacking that such an event could occur in NSW after the Ruby Princess debacle," Ms Faehrmann said in a statement.
Australian Associated Press