There were 357 new cases recorded on Saturday and the death toll rose to 61 after four women aged in their 60s, 70s, 80s and 90s, and a man in his 80s died.

Three of the latest deaths are linked to aged care where cases now span 38 facilities.

Deaths linked to aged care account for one-third of state's total, and more than 500 of the state's 3995 active cases are linked to aged care facilities - about evenly split between staff and residents.

Premier Daniel Andrews announced on Saturday personal protective equipment for aged care staff is now compulsory.

Efforts are also underway to restrict casual and part-time workers to one facility to limit spread, he said.

Victorian Opposition leader Michael O'Brien questioned why it took so long to make PPE mandatory in aged care, saying the rule should have been put in place weeks ago.

The Commonwealth and Victorian governments have established an aged care response centre to assist with workforce provisions, the prevention of outbreaks and support for providers.

Meanwhile, 42 Victorians are fighting for life in intensive care units.

"The numbers have remained stubbornly high, haven't gone up significantly, haven't gone down significantly in the past week," Victoria's chief medical officer Brett Sutton said.

"It's not going to be something that suddenly disappears in a way that wave one did."

Among clusters of infections, 183 are linked to Al-Taqwa College in Truganina and there are dozens of active cases in food production, including 45 linked to the Australian Lamb Company in Colac.

Active cases in public housing towers in North Melbourne and Flemington number 300, and there are 66 cases in Carlton public housing.

Four cases have been linked to the Catholic Regional College in Sydenham, which has been closed for cleaning and contact tracing.

Most of the state's country postcodes have only one or two cases, Professor Sutton said.

"We can see the links back to Melbourne - a lot of that is because people have to work and move into regional Victoria," he said.

Prof Sutton blamed much of the regional caseload on people continuing to work, shop and socialise while symptomatic.

One ADF officer contracted the virus while supporting testing in Craigieburn despite wearing PPE.

The premier refused to rule out further restrictions but said masks were the current strategy to stop the spread.

"Masks are effectively our stage four," Mr Andrews said.

"We can't rule out going further with rule changes, but it's a big game changer."

Police have fined 97 people in the past 24 hours for failing to abide by health directions, including 11 for not wearing a face mask.

Breaches also include a driver in Bendigo who told police he was on his way from Melbourne to visit a friend in Rochester, more than a two-hour drive away.

Three young women smoking in a parked car also copped fines after telling police they were hanging out after one had finished work.

Victoria's health department has issued a warning about fake contact-tracers trying to get payment details for testing kits.

Australian Associated Press