Queensland's Chief Health Officer Dr Jeannette Young has declared the international terminal a venue of concern.
“Anyone who was in the terminal between 9.45am and midday on Thursday, 29 April 2021, should monitor their symptoms and get tested immediately if they feel unwell,” she said.
The three flights affected are Air New Zealand NZ202 from Brisbane to Christchurch, Air New Zealand NZ146 from Brisbane to Auckland, and Qantas QF135 from Brisbane to Christchurch.
The man arrived yesterday morning on a flight from Port Moresby, where an ongoing outbreak is causing major concern in Australia's nearest neighbour.
He and his travel partner were mistakenly directed to the airport’s green departure zone, instead of the red zone for travellers from higher-risk countries, Queensland Health said in a statement Friday morning.
The pair were in the same area as 390 passengers due to depart for New Zealand for two hours before the mistake was realised.
"Staff who came into contact with this case have been placed into quarantine," Dr Young said.
Serology testing is underway to determine if the confirmed case is historical.
The pair had visited two retail outlets and used the bathrooms in the green zone of the airport.
Brisbane Airport Corporation said those areas have been cleaned thoroughly and all green zone staff were wearing PPE at the time.
Three green flights departed during those two hours, but airport officials say only "a handful" of passengers were in the vicinity of the couple.
"BAC is conducting a thorough investigation and unreservedly apologises for this human error," the operator said on Friday.
Queensland Health says it will provide an update once the results of the serology test are known.
Do you have a story tip? Email: email@example.com.