Victoria has recorded five new local cases of coronavirus as authorities scramble to find the source of an alarming new strain of coronavirus.
There was one new case in hotel quarantine which is understood to have been infected overseas.
The results come after 36,362 test results were received on Friday.
Meanwhile, contact tracers are working to find the local source of the new variant after genetic testing revealed the strain in at least two people in a family of four who travelled to regional NSW at the end of May.
Health Minister Martin Foley said the two people were unlinked cases, meaning contact tracers had not yet worked out where they contracted the virus.
One case among the remaining three revealed today is the child of the West Melbourne family that travelled to New South Wales and was later diagnosed with the highly infectious Delta strain of COVID-19.
Another is a colleague of one of the West Melbourne family members, who was already identified as a close contact.
The third is a household contact of the first worker from the Arcare Maidstone aged care home who had been isolating during their infectious period.
The Delta strain has ravaged India and is been listed as a variant of concern by the World Health Organisation.
There are also fears children are more susceptible to it than previous strains and appears to have spread further, to another family of three, through two Grade 5 children coming into contact at North Melbourne Primary School.
The cluster now comprises seven people; the family of four who visited Jervis Bay in New South Wales and three new cases — two parents and a child — reported on Friday.
No-one has been hospitalised locally yet with the Delta variant, which is a “cousin” of the Kappa strain that sparked the rest of the current Melbourne outbreak.
There are now 366 sites where exposure to the virus may have occurred.
The latest exposure sites to be added are Costco in the Docklands on May 30 between 3 and 4.30pm and 55 Collins Street – an office building in Melbourne’s CBD where a confirmed case attended for the whole day on May 25.
Chief Health Officer Brett Sutton said it was “gratifying” that three of the new cases had already been in isolation when they received positive results.
He said the two unlinked cases had been to known exposure sites, but reiterated when and where they had picked up the virus was yet to be established.
“The new cases who had not been identified as primary close contacts previously do have that link to Craigieburn Shopping Centre and Epping Plaza Shopping Centre,” he said.
“They were frequent attendees at both of those sites.”
There are 78 active COVID cases across Victoria.
On Friday, Acting Premier James Merlino said the Commonwealth would try to help Victoria meet an increased vaccine demand.
The state wants to double the number of AstraZeneca doses available to GPs, and provide an extra 100,000 Pfizer doses from mid-June for its public vaccination sites.