The next 24 to 48 hours will be crucial as Victorian health officials work to track down anyone who may have been exposed to a Wollert man who tested positive for COVID-19.
The man had travelled back to Australia from India via the Maldives and Singapore, Health Minister Martin Foley said on Tuesday.
On April 19 he landed in Adelaide, where he spent two weeks in hotel quarantine.
He returned to his home at Wollert, in Melbourne’s north, on May 4 and developed symptoms on May 8 before returning a positive test result on Tuesday.
Chief Health Officer Brett Sutton said testing was still underway but he had little doubt the man became infected in South Australia’s hotel quarantine program.
The man was in a room next to a positive case.
Victoria’s COVID-19 response commander, Jeroen Weimar, said it was a good sign the man’s household contacts had all tested negative so far.
Mr Weimar said he was confident health officials had made a good start in tracking other people who may have been exposed.
But he said if more positive cases emerged from the tier one exposure sites, it could lead to more restrictions for the wider community.
“If we’re finding positive cases at the workplace, that’ll give us a certain lead,” Mr Weimar told ABC Radio Melbourne.
“If we’re finding positive cases at the exposure sites, that would obviously be a significant cause for concern.”
Professor Sutton said there was some random luck involved in how the virus spread but “we have to work on the presumption the man is infectious”.
Mr Weimar said the task now was to find everyone who had been to an exposure site, which could be difficult due to growing complacency about the use of the QR code check-in system.
He said the owner of the Curry Vault Indian restaurant in Melbourne’s CBD, a tier one exposure site, thought there were 30 to 40 people at his restaurant on Friday night – but some did not check in.
“Based on information provided, we think there are likely to be more people in that restaurant than are on the QR code system at the moment. But we don’t know who they are,” he said.
“That’s why it’s so important that we all maintain the basic behaviours.
“Wear a mask in public transport and in taxis and when you can’t isolate, use the QR system wherever you go.”
There are a number of tier one and tier two exposure sites, which are being constantly updated on the Victorian government’s coronavirus website.
Anyone who was in a tier one site must get tested and self-quarantine for 14 days.
Those who attended a tier two exposure need to get tested and isolate until they receive a negative test result.
Mr Weimar admitted his heart sank when he learned about the new case.
“You saddle up again and ride out again for another little expedition,” he said.
“But I’m very confident [that] in the first 15 or 16 hours or so we’ve made a pretty good start.”