The health department confirmed it recorded 13 new local infections in the 24 hours to July 19 morning, one of which is a case in Mildura, previously announced by authorities.
All the new cases are linked to the current outbreaks of the Delta variant in the state, which originated in NSW.
Victoria also recorded one new infection acquired overseas, currently in hotel quarantine, bringing its total number of active cases to 81.
Stay-at-home orders are due to expire at midnight on July 20 but Premier Daniel Andrews has warned they could be extended.
Chief Health Officer Brett Sutton said further case numbers and exposure sites would determine whether the lockdown would be extended.
“Every Victorian needs to ready themself for what might emerge over the next 24/48 hours,” he said on Sunday.
“All I can say is the response couldn’t have been better. The judgements that have been made around a hard and fast lockdown have been the right ones. And that’s got us on a good track.”
Authorities estimated over the weekend that there were 10,000 “primary close contacts” in Victoria and by July 18 morning had identified 217 potential COVID-19 exposure sites across the state, some regional.
More exposure sites were announced late on July 18, including a number of restaurants, cafes and fitness centres across sites across Melbourne’s north and south-east, and a Shell petrol station in Doncaster East.
There were 54,839 test results returned during the 24 hours to July 19 and 14,758 vaccines administered.
By Benita Kolovos