A range of new exposure sites have been listed, including a superhero movie screening and a university campus.
There are now 54 active cases in the state.
All the new cases are linked to the current outbreak.
A total of 47,606 people were tested yesterday, along with 19,237 vaccines administered.
Premier Daniel Andrews said yesterday the new infections justified the need for the tough new restrictions.
“Last time, we were able to bring a more complex series of chains of transmission under control and I am very confident that our contact tracing team in partnership with every single Victorian playing their part, we will be able to do the same again,” he said.
He said it was a “positive” outcome from discussions with Prime Minister Scott Morrison.
“Those benefits will apply regardless of the five-day lockdown as opposed to the seven-day trigger point that had been foreshadowed by the Commonwealth,” Mr Andrews said.
There are currently just five essential reasons Victorians are permitted to leave their homes, including work, buying food, care responsibilities, exercise and getting a COVID-19 vaccine.
This is Victoria’s fifth major lockdown since the pandemic began, with today’s latest infection numbers coming as the state grapples with a growing number of exposure sites.
The latest outbreak is believed to be a result of three removalists who drove from NSW to South Australia, stopping in Victoria on the way, and a family who moved from Sydney to Melbourne and broke quarantine rules.
The current lockdown is set to end at midnight Tuesday, but Mr Andrews has warned it is too early to predict what will happen.