Victorians have been warned to brace for more Covid-19 infections after it was revealed the Melbourne hotel quarantine worker who has tested positive had a "high viral load" and is most likely carrying the mutant UK strain.
Despite Premier Daniel Andrews' reassurance there was "no need to panic" at a late-night press conference, officials confirmed that early tests suggest the 26-year-old Noble Park man is likely to have been highly contagious for days.
He is now under medical supervision at a medi hotel.
"Look, I think the testing of this individual indicates that he probably had a high viral load,'' Victorian CMO Professor Sutton said.
"That's what the test results show. For his very close contacts, I think there is a risk that they'll potentially become cases. That's why they're isolating from this moment forward and why their contacts will isolate as well so that, if a case occurs, there won't be further transmission to others."
The man last worked at the hotel quarantine site on January 29, the same day he tested negative for the virus.
It's a bitter blow for Victorians who endured months of lockdown last year after the second wave escaped from hotel quarantine.
Genomic testing later linked 90 per cent of subsequent cases to a family of four who infected hotel quarantine workers who unwittingly spread it throughout Melbourne ultimately claiming more than 800 lives.
The Premier said given that the UK strain of Covid had infected some of the guests at the hotel site it was reasonable to expect he had the highly contagious UK strain.
"We have to assume that this person has, in fact, infected others,'' Andrews said.
"I think we all have to assume that the international strain is, in effect, the UK strain. This thing is spreading so quickly – we've got the UK, Japan, South Africa – all of which have a higher infectivity level than what we were dealing with during 2020.
"I think the important thing to acknowledge is that people move around the state, and you can test negative, you can follow every protocol, you can be working in a system that has been copied by every other state, and still – this is such a wildly infectious virus that we could still finish up with a breach."
But mystery surrounds how he became infected and how long he has been carrying Covid in the community.
"The exact details of that are not known to us. We've got to go through that CCTV footage and all of that work. The most important thing is that we are onto this quickly," Andrews said.
The Victorian premier said there was no confirmation of a hotel quarantine breach.
"No, there has not been," he said.
"But I want to make it very clear, he has provided very detailed information and we're very grateful to him.
"Having said that, though, there'll be – and this does take some time – there's CCTV in all those hotels, opportunity, and we will work through and review all of that very carefully to make sure my answer remains accurate that there's no protocol problem.
"This is a wildly infectious virus. It is very, very challenging. We're not pursuing zero every day forever. We always knew there could be cases. We all worked together to deal with those outbreaks and I'm confident Victorians will rise to this challenge now."
The man was working as a resident support officer as part of the Australian Open quarantine programme. He's now in a health hotel and his household contacts have been isolated.
"He had no symptoms at work, tested every day at work, as every worker goes through – which is also reassuring to us, no other worker has tested positive, including those who've gone on to different workplaces," Professor Sutton said.
Premier Dan Andrews said the 26-year-old had provided detailed information about his movements.
"He works for us. So he's not a private contractor," Andrews said.
"He works for us. He works for CQV. He was a resident support officer, doing hallway duty and that sort of stuff. He's fully trained and he's been able to provide us with very detailed run-downs of where he's been and that's worth a lot in the first hours of one of these outbreaks to have all the information you need. So we're very, very grateful to him."
Andrews was first alerted at about 6.30pm on Wednesday night when his chief of staff rang. He urged Victorians not to panic.
"This is one case. There's no need for people to panic. There's no need for people to be alarmed," Andrews said.
"Victorians know what to do, and we have proven, as a state, very successful at managing these sorts of outbreaks, these sorts of issues."
Professor Sutton said he was confident Victoria could eliminate the virus again.
"We'll do it again. We will do it again. If we have to do it 10 times over, we can do it. We've got the tools," Professor Sutton said.
"No one wants to have gone through the tragic circumstances that Victoria has, but you cannot have that occur and not embed those lessons to make sure that you're in the very best position going forward."