Victoria has recorded just one new coronavirus case and no deaths as 800 people connected to an outbreak in Melbourne's northern suburbs remain in isolation.
Premier Daniel Andrews on Friday confirmed the state's single case was a parent of a student at East Preston Islamic College.
He said there was no clear link between the new case and a grade 5 student at the school who tested positive on Wednesday.
"That is why it is a little bit uncertain and we have to try run that to ground. There is obviously some virus in that local community," Mr Andrews said.
Some 400 people linked to the school are self-isolating.
The state's Commander of Testing Jeroen Weimar urged members of the school community to get tested for COVID-19 even if they do not have symptoms.
"We now have two positive cases in the broader school community and although they are not linked at this point, we are keen to ensure there are no other traces anywhere else in that wider community," he said.
Another 400 primary or secondary contacts linked to the northern suburbs outbreak are also self-isolating.
Daily checks will occur over the 14-day period to ensure they are doing well and complying with arrangements.
Authorities had been monitoring an outbreak in the area, totalling 36 cases, for a fortnight and considered it contained until the grade 5 student attended school while infectious on Monday and Tuesday.
The student was meant to be self-isolating after a household member earlier tested positive to the virus.
Mr Weimar said arrangements between the Department of Health and Human Services and the Department of Education were now in place to identify students who should be isolating.
He thanked the almost 19,500 Victorians who came forward for testing on Thursday, including 6500 in the northern suburbs.
Some 86 residents of a Broadmeadows social housing block have been given the all-clear to leave their apartments after returning negative tests.
Another 30 residents are expected to be tested over the coming days.
"I would urge all residents not only of the housing block in Broadmeadows but generally across northern Melbourne, please monitor yourself very closely for symptoms, he said.
"If you have any concerns at all, come forward to get tested."
Authorities are continuing to doorknock residents of Broadmeadows, Dallas, Preston, Roxburgh Park and West Heidelberg to get the message out.
Meanwhile, sewage tests suggest there could be a positive COVID-19 case in Ararat, about 200km west of Melbourne.
A pop-up testing site has been established at East Grampians Health Service.
"We clearly have some activity happening in the Ararat area. We are very keen to identify whether this is an old case or whether this is a new case that's developing," Mr Weimar said.
There are 42 sewage surveillance sites across Victoria.
Melbourne's 14-day case average has dropped to 5.5 and mystery cases for the fortnight to October 22 remain at 10.
Regional Victoria's 14-day average remains at 0.3 with no mystery cases.
The state's death toll stays at 817 and the national figure at 905, with only one death in the past week.
The premier said the state was "very well placed" to further ease restrictions on Sunday.
"We are confident in where things are at at the moment," Mr Andrews said.
"I can't predict what the numbers will be tomorrow but the strategy is working, the trend is with us, the numbers are falling and that is a very good thing."
The premier said he was also confident there would be flights into Melbourne again from interstate and overseas by Christmas.
Australian Associated Press