COVID Commander Jerone Weimar has identified the Shepparton COVID case as a man in his 30s.
"Shepparton remains, of course, on lower restrictions than Melbourne and it's very important we identify any linkages to this case, we'll have more to say over coming days," he said.
Mr Weimar said the man's family was being tested today.
He said two children in the family attend St Mel's Primary School which has been shut down.
Mr Weimar asked people who do not have symptoms to get tested tomorrow not today.
He said it was not yet known where the man contracted the virus.
Asked if a regional lockdown was on the cards, Mr Andrews said nothing could be ruled out.
"We are asking people in Shepparton to come forward and be tested," he said.
Three testing sites are being stood up today.
Today is a bad day, Victoria Premier Daniel Andrews has said as the state recorded 57 new cases.
While no restrictions would be announced now, Mr Andrews said he couldn't rule announcing more soon.
"This is very, very serious," he said.
If the outbreak gets away any more, there will be hundreds of daily cases and hundreds of people in hospital, Mr Andrews said.
"If we have a weekend this weekend like last weekend, well, then next week it will be like Sydney," he said.
"Simple as that. This will get away from us, we have too many mystery cases out there."
Mr Andrews said "we are right on the edge of this getting away from us".
"The question is do we spiral out of control or don't we," he said.
Earlier today Goulburn Valley Health confirmed a Shepparton resident had tested positive for COVID-19.
It came after COVID fragments were detected in the town's wastewater three times recently.
IN OTHER NEWS:
Extra drive-through testing sites are being set up in the region and Goulburn Valley Health chief executive Matt Sharp urged residents with any symptoms to get tested and isolate at home until they received their results.
Of the new local cases, 30 were infectious while in the community.
49 of the cases are linked to known outbreaks, the rest are mystery cases.
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