In less than two days, an outbreak of coronavirus in Victoria prompted the closure of the state’s border with New South Wales and saw Western Australia slam its border shut to Victorians.

Health authorities are urging Victorians right across the state to get tested with even the slightest symptoms, with one case already detected in Gippsland.

How did the outbreak begin?

Contact tracers are still working to find the “index case” that triggered the outbreak, but all 10 of the outbreak cases detected so far can be traced back to a restaurant dinner on December 21.

Two separate groups of diners sat down at adjacent tables at the Smile Buffalo Thai restaurant in Black Rock, in Melbourne’ south-east, for a meal.

Three of those people have since tested positive to coronavirus, with the other seven cases linked as close contacts.

Empty chairs and tables inside a restaurant, where the bar is decorated with blue tinsel.
Mr Weimar said the Smile Buffalo Thai restaurant’s strong record keeping had made the job of contact tracers much easier.(ABC News: Kyle Harley)

Department of Health and Human Services (DHHS) COVID-19 response commander Jeroen Weimar said authorities were chasing up three potential links to New South Wales related to this cluster, dubbed the “Mitcham-Mentone cluster” due to the postcodes of the cases.

The first lead, a person who had returned from NSW and also dined at the restaurant, has returned a negative result for coronavirus.

But Mr Weimar said they would remain in quarantine until blood test results came back, hopefully before the end of the weekend, to reveal whether they had ever been infected with coronavirus.

“That will determine whether they have already cleared their infection and stopped shedding the virus, whether they have previously had the infection or whether they’ve been negative all the way through,” he said.

Two other people had been in Sydney for around 24 hours “a couple of weeks ago” before coming back to Victoria, and were close contacts of positive cases, Mr Weimar said.

He said health authorities were also running blood tests and genomics testing on those two people.

While December 21 is the earliest date authorities have at the moment for the outbreak, Mr Weimar stressed that it could have begun earlier.

He said it was critical for Victorians with even the slightest coronavirus symptoms to get tested.

“If you’re sitting around any other part of Victoria thinking you’re not feeling 100 per cent you may be part of that other new chain of transmission that we don’t have identified,” he said.

“The only way we spot these clusters is if people get tested.”

After thousands of Victorians heeded that message, many testing sites in the state have been overrun.

The latest DHHS information on testing sites can be found here.

Where has it spread to since then?

As of Friday morning, health authorities had 170 close contacts in quarantine and dozens more of their contacts (secondary contacts) quarantining as well.

But among the 10 cases, one is in the regional Victorian town of Leongatha in Gippsland.

Mr Weimar said that person had only recently travelled to Leongatha to rent a holiday house, but it was likely there would be exposure sites listed from the area.

There is also a close contact of a case in quarantine in Barwon Heads, on the Bellarine Peninsula.

The Royal Brighton Yacht Club glass door is shut, with an A4 sheet apologising for its closure.
The Royal Brighton Yacht Club is among the most high-risk exposure sites identified by contact tracers.(ABC News: Kyle Harley)

Two of the latest positive cases are in people who were also at the Black Rock restaurant on December 21, before they travelled into Gippsland, a government spokesperson told the ABC.

They stopped in Lakes Entrance on December 28 and 29 — the latter being the same date coronavirus fragments were detected in Lakes Entrance wastewater.

They then headed to New South Wales, where they attended two hospitality venues in Eden and Bermagui on December 30 and the morning of December 31.

By the time Victorian health authorities contacted them on December 31 to inform them they were close contacts, they were already queuing to be tested at a NSW site.

They are now back in Victoria being supported to isolate.

Exposure sites are being regularly updated, refined and amended on the health department’s website, but as of Friday morning these were the five most-important exposure sites:

  • The Smile Buffalo Thai restaurant at Black Rock, on December 21 between 6:30pm and 9:40pm, where a case had dinner
  • The Royal Brighton Yacht Club in Brighton on December 29, between 12:00pm and 1:30pm, where two cases dined whilst infectious
  • The Holy Family Parish Doveton Catholic Church in Doveton, on December 26 between 4:00pm and 6:00pm, where a case attended a Spanish service
  • The Woodlands Golf Club’s clubhouse bar at Mordialloc, on December 23 (times unclear) and December 28 between 4:40pm and 5:15pm
  • The Village Century City cinema at Glen Waverley on December 28 from 2:45pm and 5:30pm, in particular the 2:45pm Gold Class screening of Wonder Woman 1984

Anyone who has visited these sites must get tested immediately and quarantine for 14 days from the exposure date.

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Health authorities are urging Victorians to get tested with even the slightest symptoms.

Mr Weimar said all the venues and communities involved had been very cooperative, including the Doveton church community, where around 100 people attended the December 26 service.

“I know it would have felt, even a few days ago, for many businesses, ‘why do we need to keep writing all these names and addresses down, why do we need to remind people to do QR codes?'” he said.

“This is why. Nobody at Brighton Yacht Club four days ago would have thought that it was necessary to record their details when going in for a drink. This is why it’s important.”

Mr Weimar said the 13,108 tests conducted on Thursday needed to grow Friday and in coming days to give authorities confidence that they were not missing chains of transmission in the community.

“My appeal would be: don’t think this is just a bayside suburbs, Mitcham issue, it is not only a Melbourne issue, it is a Victorian issue,” he said.

Could the outbreak have come from somewhere other than NSW?

Mr Weimar said authorities would continue to pursue any fresh leads that were uncovered as a result of contact tracing, but so far the NSW leads appeared to be the most “promising link”.

“At this point in time we have found no other connection to any other area of infection … there is no connection at this point in time to any aspect of the hotel quarantine program or to any of the staff members involved in that.”

He said authorities had conducted more than 25,000 COVID-19 tests on staff involved in the hotel quarantine program, all of which had been negative, which meant authorities were “very confident” they were not detecting coronavirus in that cohort at this point in time.

What does it mean for Victoria’s borders?

Thousands of Victorians queued for hours on roads on Thursday night in a bid to get back from New South Wales before midnight to avoid quarantining for 14 days.

Those who made it across before midnight on New Year’s Eve must get a test and quarantine at home until they receive a negative result.

People arriving up until 11:59pm on Friday night must get tested and quarantine at home for 14 days.

From Saturday, people have been told they will be turned around at the border.

A checkpoint on the Lincoln Causeway in Wodonga following the Victoria border closure
Victorian police officers are checking the permits of those seeking to cross the NSW border before it closes at 11:59pm on Friday.(ABC Goulburn Murray: Mikaela Ortolan)

Mr Weimar said mandatory hotel quarantine would be required for those permitted to enter the state with exemptions, but stressed those exemptions would be very limited and Victorians should return before the border shuts.

“We did not design the hotel quarantine system, to enable people who went on holiday in NSW to come back a bit later,” he said.

“We need to ensure that people have got back.”

Mr Weimar said people in Queensland or the ACT wanting to drive back into Victoria would be able to apply for transit permits soon, which would allow them to make the journey with certain conditions to limit infection risk.

“We will be making arrangements after tomorrow for people who need to transit across NSW from other states,” he said.

Western Australia has shut its border to Victorians in the wake of the outbreak, after the state went in an instant from “very low risk” to “medium risk”.