Health authorities say all the cases are linked to current outbreaks but were not in quarantine during their infectious periods.

The state administered 22,335 vaccine doses in the 24 hours to Friday evening and conducted 43,618 tests.

Victorians are bracing for more exposure sites spread across wider parts of the state amid the race to contain the Delta variant.

Residents have woken to another weekend in lockdown and with more than 10,000 close contacts of positive cases now isolating.

The exposure site list grew to more than 75 venues on Friday, including two tier one sites - a medical centre and a pathology collection centre, both in Caroline Springs.

See the exposure sites here.

Several schools were also added as tier two sites, including Heathdale Christian College in Werribee and Warringa Park School in Hoppers Crossing, after positive cases were found in students.

COVID-19 Commander Jeroen Weimar warned Victorians the number of exposure sites would continue to grow.

"We'll see exposure sites start to spread across wider parts of the city and potentially regional Victoria," he said.

The statewide seven-day lockdown began at 8pm on Thursday, with the same stay- home rules that applied during last month's lockdown reimposed.

Health Minister Martin Foley warned the state was in "a precarious position" and said lockdowns would remain a feature of Australia's public health response until enough of the population is vaccinated.

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