An infectious diseases expert has warned that Victoria is "primed" for a third Covid wave as new virus exposure sites continue to filter through at the beginning of the state's 7-day, snap lockdown.
The Department of Health currently has 121 sites listed on its website, however Acting Premier James Merlino warned on Thursday locations had reached 150.
Among the most recently identified Tier 1 sites are Focus Health and Fitness gym in Yarraville, Network Public Par in inner-city Docklands and The Coffee Club at Craigieburn Central.
A Bunnings store in Thomastown and a Chemist Warehouse in Greenvale have been identified as Tier 2 locations.
Health authorities remain concerned over the time positive cases have spent in the community, with more than 10,000 primary and secondary contacts identified.
Locations linked to the 26 locally acquired Covid-19 cases now stretch from the NSW border to the southern end of the Mornington Peninsula.
Victoria 'primed' for third wave
Infectious disease expert Dr Michelle Ananda-Rajah from Monash University said she feared for Victoria due to a combination of factors.
"I think the stakes are higher this time because we have all the factors for what is essentially a perfect storm," she told ABC News Breakfast.
She warned an unvaccinated population, the arrival of winter and an "unforgiving" variant meant Victoria was "primed" for a third wave.
Chief Health Officer Brett Sutton said he was concerned over the outbreak but he did not believe daily cases would surge into triple digits like they did in the state's unrelenting second wave last year.
Mr Merlino said without change the outbreak could become "increasingly uncontrollable".
Following the introduction of the lockdown at midnight overnight, people are now only able to leave home for five reasons - to shop for food and essential items, provide or receive care, exercise, work or study if they are unable to from home, and to get vaccinated.
To allow more Victorians to get the jab, those aged 40 to 49 are now eligible for the sought-after Pfizer vaccine.
"The vaccine is really our only ticket out of this," Health Minister Martin Foley said.
However, Dr Ananda-Rajah said the Pfizer jab should also be made available to elderly Australians who are most vulnerable to severe illness and death.
The lockdown, seeded in South Australian hotel quarantine, has again raised questions about the capability of Victoria's contact tracing system, which was partially blamed for the state's second 112-day lockdown.
Chief Health Officer Brett Sutton said it was "absurd" to suggest contact tracing was failing.
Dr Ananda-Rajah said the number of contacts so far traced was "phenomenal".
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