Victorian health officials have rushed to identify six people who shared the floor of a South Australian quarantine hotel where Covid-19 leaked before infecting at least one person.
The Department of Health fear all six may have been exposed to the virus on the third floor at the Playford Hotel in Adelaide.
Health authorities previously confirmed a man who tested positive on Tuesday had acquired the virus from a positive quarantine guest staying in the adjacent room to him at the Playford.
After spending time in the community, 90 of his close contacts have returned negative results with health authorities awaiting the results of 30 more.
Multiple exposure sites have been identified in relation to the case in Melbourne's northern suburb of Wollert, including a packed train service from the CBD which was likely to be carrying hundreds of AFL fans, Health Minister Martin Foley said.
All six people have been contacted and now must undergo testing and an additional 14-day quarantine stint. The movements of these people within the community is so far unclear.
Ten people have been identified from the hotel in South Australia.
The state government has vowed to crack down on businesses not using QR code check-ins after one of the exposure sites, the CBD's Curry Vault restaurant, was found not to be enforcing its use among customers.
In response, the state government on Thursday announced businesses breaking check-in rules will face a new $1,652 on-the-spot fine, and further penalties of up to $9,913 and prosecution for repeated breaches.
Checks last week showed more than a third of businesses were not complying with QR code rules.
Acting Police Minister Danny Pearson said those not complying were "letting down" Victorians after the state fought to defeat its deadly second wave.
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