Victoria's health authorities fear contact tracers may have missed hundreds of Melbourne patrons as they announced the city's surge in Covid-19 cases is being treated as two outbreaks.
Victoria's Department of Health testing chief Jeroen Weimar said a separate outbreak had now developed from the Port Melbourne office of Stratton Finance after a case from the Whittlesea outbreak in the city's north visited that office infecting others.
Mr Weimar said of the four new cases three are associated with the Whittlesea outbreak and one is a close contact of a positive case of the Stratton Finance, Port Melbourne outbreak. He said that fourth case spent time with a positive case at a sporting club on May 23.
The Department of Health said as of 1pm Thursday 96 contacts were linked to the Stratton Finance exposure site. All previous positive cases detected in this outbreak were staff, plus Friday's new case.
A total of 84 staff had been identified as contacts on Thursday, and 82 had returning negative tests by Thursday.
Five Melbourne bars are key exposure sites
Mr Weimar identified five hospitality venues that were of most concern to health authorities, including the Sporting Globe bar in Mordialloc where he says transmission has occurred.
The four other venues are the Three Monkeys bar and Somewhere bar in Prahran, the Palace Hotel in South Melbourne and The Local in Port Melbourne. Times of exposure can be found on the Department of Health website.
Mr Weimar said "hundreds" could have been exposed at each of the venues, however QR check-in data did not match these estimations. He warned it was vital people checked in at venues to allow for tracers to work out how many people may have been exposed.
"The five sites I went through a particular concern to us because essentially, they are clubs, social contacts, places where we expect to see significant numbers of people in close proximity, dancing, singing, doing what they do," he said.
Earliest case infectious in community for nearly two weeks
The current index case has had his symptoms onset date revised to May 13. Chief Health Officer Brett Sutton confirmed that meant he had spent 12 days in the community potentially infectious.
Mr Sutton said "the key" is to believe anyone can contract the virus, and should seek testing at the earliest onset of symptoms.
"Do not think that it is something else. You have to work on the assumption that it is COVID," he said.
"We can't emphasise it enough."
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