The Victorian government is poised to announce a lockdown as Covid-19 case numbers in the state continue to climb, the ABC reports.
South Australia on Wednesday enforced a hard border with residents of Greater Melbourne, as authorities revealed the man at the centre of the outbreak was likely to have caught it in Adelaide hotel quarantine.
Senior Victorian ministers met overnight to discuss the latest developments.
On Wednesday morning, Acting Premier James Merlino had said he could not rule out “taking some further action”.
“It’s fair to say that the next 24 hours are going to be particularly critical,” he said.
The last time restrictions were tightened in Victoria was in February, when an outbreak growing to 13 cases prompted a five-day snap lockdown.
While all the cases in this outbreak have so far been linked to each other, which is considered a positive sign, authorities are concerned about a growing list of high-risk exposure sites linked to the new infections.
There are now more than 70 exposure sites – some dating back more than a week – spread across multiple Melbourne suburbs and at least two regional locations.
The full list can be found on the health department’s website and is being regularly updated.
In urging people to be tested, Chief Health Officer Brett Sutton said “there could be other cases out there”.
University of Melbourne epidemiologist Tony Blakely said while most of the recent cases were already isolating after being identified as close contacts, the growing list of exposure sites was cause for concern.
“I’m not sure we can realistically assume our contact tracing will keep ahead of it, but I hope it does. But boy oh boy, that’s a big ask.”
The outbreak started with a Wollert man who, according to South Australian authorities, likely contracted the virus through aerosol transmission in an Adelaide quarantine hotel.
Authorities now believe the fifth man diagnosed, who had symptoms and was out in the community for days before being tested, could have infected many of the others in the cluster.
But they are still searching for the “missing link” that connects the outbreak to the Wollert man.
“It’s just hard to believe that it hasn’t got beyond the layer of people who are already in isolation or quarantine,” Professor Blakely said.
Tighter mask rules and gathering gaps have been reintroduced in Melbourne to respond to the outbreak, but life otherwise remains as normal for most of the city.
Professor Sutton, the Chief Health Officer, said “everything is on the table” while authorities reviewed restrictions, which included large public events like AFL games.
While he said it was too early on Wednesday to know whether further restrictions would be needed, Professor Sutton said any lockdown would be broad, rather than localised in the city’s north.
Sutton said there were “a whole bunch of elements we always look at” before making any further changes.
Those factors included how many more people tested positive, the type and number of exposure sites they generate and how long they had been out in the community.
Also worrying was that cases have contracted a variant of concern – the B1617 strain which was first detected in India.
It is understood to be just as infectious as the B117 strain that was spreading at the time of the February lockdown.
Former president of the Australian Medical Association and Altona GP, Mukesh Haikerwal, said he expected a lockdown would be imminent if more cases were identified.
“We’ve been tough on our population previously and I expect we will get there again,” he said.
Haikerwal has previously been critical of the state’s contact tracing efforts, but said he was confident “we have got a department that’s tuned into this”.
There have been some concerns raised about exposure sites not being listed on the health department’s website hours after being identified.
Sutton on Wednesday commended the “extraordinary” work of contact tracers in chasing down generations of the virus in the community.
The state’s outdated record-keeping was highlighted as a problem during the deadly second wave, but significant upgrades have been made in the last six months.
University of Melbourne professor Jane Tomnay, who chaired the expert advisory group to review the Australasian contact tracing guidelines, said the tracers were “doing extremely well”.
“And I think that they’ve really upscaled the capacity in the state to do contact tracing to meet the needs of the pandemic exceptionally well.”