A woman who left Melbourne while it was in lockdown and went on a road trip through three states has tested positive for coronavirus in Queensland.
Regional centres in NSW and Queensland are on alert after the woman's case was confirmed on Wednesday.
She and her husband left an unidentified suburb on the edge of greater Melbourne on June 1, while the Victorian capital was in lockdown to control community transmission of the virus.
They then travelled through regional Victoria, crossed the border into NSW where they visited regional centres, and then entered Queensland on June 5 - two days after she started showing symptoms of coronavirus.
But Queensland's Chief Health Officer Jeannette Young has said it is possible the woman was infectious from the day she left Melbourne.
Authorities in NSW have issued alerts for several regional centres after the couple stopped in Forbes, Dubbo, Moree and Gillenbah.
Queensland's list of exposure sites include a McDonalds restaurant in Goondiwindi, where they crossed the border from NSW, and sites on the Sunshine Coast, including at Moffat Beach, Kings Beach, Buddina, Baringa and Caloundra.
The couple also travelled through Toowoomba, west of Brisbane. The list of exposure sites is on the Queensland Heath website and will inevitably grow.
The Sunshine Coast region has been sent double the amount of coronavirus vaccine it normally receives and Dr Young has urged residents to get their shots, and front up for testing if they develop symptoms.
Six close contacts of the woman have been identified so far, including her husband who has to date tested negative.
But Dr Young fears he could become infected, given how much time the pair spent in the car together. Both are now at the Sunshine Coast University Hospital.
Queensland Police Deputy Commissioner Steve Gollschewski has promised to thoroughly investigate why the couple left Melbourne when a lockdown was in place, and warned that anyone who defied health directives could end up in court.
"We've got a couple that have come from Victoria, when Victoria's in lockdown, into Queensland," he told reporters.
"All the aspects of how that's occurred, including what's happened in the other states ... we'll examine all those issues."
Health Minister Yvette D'Ath said much would depend on the results of testing over the next few days.
"If you have been to one of the exposure sites, whether you have symptoms or not, we would like you to come forward and get tested," she said.
The scare came after Victoria announced its two-week lockdown would end at 11.59pm on Thursday but Melburnians will need to remain within 25km of their homes, unless working or studying, care giving or getting a COVID-19 vaccine.
In response, Ms D'Ath said Queensland would from 1am on Friday only consider Greater Melbourne a coronavirus hotspot.
That means that Victorians from outside Greater Melbourne can travel to Queensland without needing to quarantine.