Victoria has reported another five new coronavirus cases as the statewide lockdown enters its fourth day.
The Department of Health said there were 16,752 vaccine doses administered in the past 24 hours to midnight and 43,874 test results were received.
The state's latest outbreak has now reached 45 infections.
The new cases come a day after Arcare Maidstone aged care facility in Melbourne's northwest went into lockdown after a staffer tested positive for Covid-19, with the case a mystery as there is no known contact link to the virus.
At least one resident and a second worker at the aged care facility have now tested positive for COVID-19 after coming into contact with the infected staff member.
Three more aged care centres affected
Three other aged care facilities in Melbourne have too been affected by the coronavirus outbreak.
In a letter obtained by Melbourne radio station 3AW, a staff member at the BlueCross Western Gardens tested positive for the coronavirus.
It is believed the staff member was a close contact of the mystery case at Arcare Maidstone.
The Age reports two other Melbourne aged care centres are of concern after staff members also worked at Arcare Maidstone.
According to the newspaper, chief executive of Royal Freemasons, Kerri Rivett, said in a letter on Sunday afternoon that the Coppin Centre in Melbourne and the Freemason's Footscray centre had been affected and residents were self-isolating.
No staff or residents at these two aged care facilities have tested positive.
“We have just been notified that clinical staff members at our Coppin Centre and Footscray homes have last week, worked at another aged care provider where a staff member has now tested positive for COVID-19,” she said in the letter.
“The potential exposure occurred during work at the other provider and all staff were wearing a mask. Within our homes, staff have also been wearing masks at all times.”
The mystery case at Arcare Maidstone, a woman in her 50s, wore a mask when she last worked on May 26 and May 27 but did not have any symptoms until the next day and later tested positive.
The Altona woman, one of five local cases reported on Sunday, tested positive despite receiving her first dose of the coronavirus vaccine on May 12.
It is possible she was infectious during shifts on Wednesday and Thursday.
Only a third of Arcare Maidstone's 110 staff and 53 of 76 residents have been vaccinated so far, with the federal government bringing forward scheduled vaccinations to Monday.
40 locations added to exposure site list
The Royal Freemasons facilities were not among the 40 locations added to the state's list of exposure sites on Sunday.
The new sites include a soft drink factory in Thomastown, a number of bus routes in Melbourne's north and various stores at Chadstone shopping centre.
Craigieburn's Willmott Park Primary School was closed on Monday with nearby Mount Ridley College listed as an exposure site after a pupil tested positive for COVID-19 on Saturday.
Acting Premier James Merlino said no decision has been made on whether the state's seven-day lockdown will end on Thursday evening as planned.
"This is something that is evaluated every hour of every day," he said on Sunday.
The full list of exposure sites can be viewed on the Department of Health and Human Services website.
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