The virus is spreading across Australia again - this is how
Disease experts warned Victoria's coronavirus outbreak could lead to a second wave in other states and territories - now their predictions appear to be coming true.
The ACT, the Northern Territory and now NSW have all recorded positive COVID-19 cases linked to the Victorian outbreak, including a teenager testing positive in the town of Merimbula.
And a screening debacle after the arrival of a Jetstar flight has sparked fresh fears about infections spreading.
NSW citizens returning from Melbourne were allowed to disembark and leave before being screened.
Ten News reported on Wednesday night the majority of passengers were brought back into the airport, but 48 had managed to leave.
NSW Health has now contacted all but three of those passengers, one of which has refused to be screened.
"The probability of contagion in NSW given what's happened in Victoria is extremely high," NSW Premier Gladys Berejiklian admitted on Wednesday as she foreshadowed tougher measures.
These include forcing people coming from Victoria into NSW into mandatory 14-day hotel quarantine, which they would have to pay for themselves.
And residents of border communities are banned from rest of the state, with the premier considering "moving" the border north, closer to Wagga Wagga, to exclude potentially infected border town residents.
But anecdotal reports suggest Victorians had already been pouring into NSW in cars and caravans even before queues at border choke points such as Albury-Wodonga began forming ahead of the midnight Wednesday border lockdown.
Ms Berejiklian is also considering a hard lockdown of Albury from the rest of NSW and warned people not to visit it or any other border town "unless it is absolutely necessary".
Infectious diseases expert, Professor Mary-Louise McLaws has warned that other parts of
Australia are "absolutely" likely to see similar COVID-19 spikes to Victoria.
"Particularly out into the regional areas," Professor McLaws said.
"So everybody in Melbourne during the school holidays must not be travelling to regional areas.
"They must stay at home, because you don't want it escaping, because then we will be in even worse trouble."
The spread of COVID-19 had already begun last week when the Northern Territory recorded its first coronavirus case in three months.
A Darwin resident who had returned from overseas and spent two weeks in quarantine in Melbourne then stayed with a family for several days in one of the 10 virus alert postcodes.
The person, who is aged in their 30s, then flew Melbourne-Brisbane, Brisbane-Darwin, arriving in Darwin on June 29 feeling unwell and then testing positive.
The person was taken to Royal Darwin Hospital and placed in isolation.
In NSW, a Melbourne teenager on holiday with his family in the NSW south coast town of Merimbula has now tested positive after five days in the town.
He had been cleared of coronavirus in Melbourne, but later discovered that test was a false negative.
It is unclear if the teen was tested with the less invasive saliva test, which is believed to be less accurate than the swab tests of throats and noses.
The saliva tests were introduced after 30 per cent of returning Victorians in hotel quarantine refused swab testing.
The only place the teen and his family visited was Merimbula's Tathra Hotel, which had taken the details of 80 patrons there at the time.
NSW Health has contacted all of them and Chief Health Officer Dr Kerry Chant the risk to other patrons "has been assessed as very low".
Dr Chant said the family's conduct had been "exemplary" and they did all the right things, but "there is a lot of testing and there will occasionally be these errors".
Three Canberra residents from the same household have tested positive for coronavirus, the ACT revealed on Wednesday, a month after the last known positive case in the territory.
All three people, one woman and two men, all aged in their 20s, are linked to the outbreak in Victoria, two having arrived back from a Melbourne hotspot.
The third was infected in the household and all are now self-isolating.
The ACT's last known case on June 6 had been a foreign diplomat who became infected while overseas.
NSW Premier Berejiklian is reportedly planning to make a new announcement about restrictions on public gatherings as Victoria's still burgeoning virus numbers has given other states a case of the jitters.
She said "basic things like sharing a salt and pepper shaker" were a health risk
In Victoria, as the whole of Melbourne braces for a six-week lockdown from midnight, 41 people are in hospital, with seven fighting for their lives in intensive care beds, and the state just recorded a daily increase of 134 new cases.
Dozens of cases from the Melbourne outbreak have been traced back to quarantine breaches, as the scandal, which included guards sleeping with quarantining returned travellers, heads for a judicial inquiry.
As NSW recorded eight new cases of COVID-19 on Wednesday, seven from hotel quarantine, it was revealed health workers at Liverpool Hospital in southwestern Sydney may have been exposed.
A woman in her 30s from Sydney's southwest. is the eighth case and health authorities are now investigating possible sources of the infection, although it is not believed to be linked to Victoria.
Her close contacts and staff from Liverpool Hospital have been advised to seek testing and self-isolate.
Flagging further looming restrictions, the NSW Premier said on Wednesday that her "level of concern will translate into tougher decisions [if necessary]".
"The probability that we need to be tougher on broader restrictions is extremely high," she said.
"The government is considering what further action we take to make sure the bubble of these border communities is maintained."
The premier urged anyone on the NSW-Victoria border to get tested if they had even the mildest symptoms, as well as those in tourist towns like Byron Bay which has been flooded with Victorians on school holiday,
"Sometimes infection can bubble under the surface for a month," she said.
Originally published as How virus is spreading across Australia