Victoria has reported four new cases of coronavirus bringing the Melbourne outbreak total to nine.
The state reported the new cases on Tuesday afternoon after announcing just one new infection earlier on Tuesday morning.
The four new cases are all family contacts of the fifth case announced this morning.
The cases come after four locally acquired cases emerged on Monday – a man in his 30s, a woman and man in their 70s and a pre-school aged child.
The outbreak grew to five on Tuesday morning with a man in his 60s also testing positive.
The man developed symptoms on 17 May and presented for testing yesterday. The individual is a close contact of a positive case detected yesterday.
"This virus is awful in the way that it can spread," Chief Health Officer Brett Sutton told ABC Radio Melbourne on Tuesday.
"Sometimes you can be absolutely lucky with a single case who's not particularly infectious ... You can be very unlucky with rare cases that are particularly infectious that have been to lots of places and transmit it to lots of people."
He added people had to be "alive to the possibility" that the number of cases could grow.
Victoria’s Department of Health said in a statement genomic sequencing had confirmed the four cases detected on Monday had the same strain as a Wollert man who contracted the virus in hotel quarantine in South Australia earlier this month.
Professor Sutton said genomic sequencing had also determined they were infected with the B.1.617 mutation, also known as the Indian variant.
He told 3AW on Tuesday afternoon cases in the Whittlesea outbreak had not been linked to an exposure site blunder where the government said the Wollert case visited Epping Woolworths while infectious rather than Epping North.
New warning for Highpoint Shopping Centre
CCTV footage from the Highpoint Shopping Centre has allowed the Department of Health to identify which stores one of the positive cases visited.
People who visited the listed stores during specified times must get tested and quarantine for 14 days.
Those who visited floors two and three of the centre during specified times are also urged to get tested and isolate until they return a negative result.
One of today's confirmed cases attended Broadmeadows Hospital on May 21.
It is not currently listed as a public exposure site as the department has access to records of everyone who attended the hospital.
Melbourne faces new Covid restrictions
Victorian Deputy Premier James Merlino announced a number of new restrictions for greater Melbourne in effect from 6pm tonight.
Private gatherings in greater Melbourne will be limited to five people while public gatherings will be limited to 30.
Face masks will also need to be worn indoors unless an exemption applies.
Mr Merlino said a mask was required for everybody aged 12 and over.
Schools and workplaces remain open and Victorians who live in greater Melbourne can still travel to regional Victoria. However, they will still have to follow rules as if they were in greater Melbourne.
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