The Australian state of Victoria is in the middle of a second wave of coronavirus, recording a massive 75 new cases today.

Health minister Jenny Mikakos said one of those cases was in hotel quarantine, 14 are linked to outbreaks, 37 were detected through routine testing and 23 are still under investigation.

The 75 cases were detected in more than 15,000 tests.

Mikakos said 271 of Victoria's cases were from community transmission and 288 cases were still active.

Nine Victorians are in hospital, one is in intensive care.

"These are clearly big numbers today. It's absolutely concerning," chief health officer Professor Brett Sutton told reporters.

Victoria Premier Daniel Andrews also said he will consider locking down individual hotspots pending the results of a 10-day testing blitz.

New South Wales recorded seven new cases today – all in returned travellers who will spend the next 14 days in hotel quarantine.

Queensland again recorded zero new cases and with just two active cases is likely days away from declaring itself Covid-free.

Health minister Jenny Mikakos said a number of outbreaks in Victoria were also linked to schools.

"Obviously there have been school holidays, those schools are already closed and all the schools will be thoroughly cleaned and there will be contact tracing there involving both staff and students being followed up and obviously the school communities being notified," she said.

The schools are Queen of Peace Parish Primary School in Altona Meadows, Aitken Hill Primary School in Craigieburn, Fitzroy High School and Port Phillip Specialist School and St Bernard's College in Essendon.

Two childcare centres in Abbotsford and Pascoe Vale – both from the Guardian chain – have also been shut.

"We have a healthcare worker that's tested positive at the Melbourne clinic in Richmond and close contacts among both patients and staff will be identified and contacted and the facility will be cleaned," Mikakos said.

"We also have a staff member at the Red Cross processing facility, that's called the Lifeblood Red Cross processing facility, and there is contact tracing under way and cleaning will be undertaken as well."

Health minister Jenny Mikakos said she was "concerned" about the massive uptick in Victoria's cases, also confirming that one of Melbourne's clusters had linked up with another.

"There is now a link that has been established between the North Melbourne family outbreak and the Brimbank family outbreak," Mikakos said.

"Four of the new cases have been linked to this outbreak, and the department is investigating the exact nature of the link there.

"We also have three new cases that are security contractors who were already in quarantine from the Stamford Plaza, so they have undertaken their day 11 tests as is standard practice where we have an outbreak, so those people are already in quarantine as part of that, that brings that total to 23."

Ten cases have been linked to the Wollert family outbreak, four have been linked to a new family outbreak in Lysterfield and Pattersons Lakes, and five are a new family outbreak in Truganina.