The Department of Health and Human Services said on Friday that masks would continue to be a "a critical tool" in fighting the virus.

But three epidemiologists contacted by The Standard all said they would not be against mandatory mask wearing being reduced to indoor spaces, public transport and outdoor crowded settings.

University of Melbourne epidemiologist Tony Blakely said he had modelled a "second phase" of eased mask wearing that he believed Victoria could enter into soon.

"I wouldn't be opposed to it (now), but I (also) wouldn't be opposed to us not moving to it until a little while," Professor Blakely said.

"Masks don't really need to be on when you are walking down the beach."

Deakin University's epidemiology chair Catherine Bennett said face masks had been effective in stemming the spread of the virus.

"We do know in regional Victoria it made an immediate difference when it was introduced," Professor Bennett said.

But she said she was preparing a submission to the government to ask for mask wearing to be mandatory only in crowded settings.

Professor Bennett said she supported mask wearing in settings such as public transport, in cafes, among older school students, in grocery stores and crowded spaces.

"Wearing them beyond that runs the risk of disengaging people and having such poor compliance," she said.

"I think we are going to keep people on board for longer when we are asking people to wear it where it is smart and makes more sense in terms of the transmission."

La Trobe University epidemiology Associate Professor Hassan Vally said given the low levels of transmission he believed mask wearing could loosen.

"From a purely scientific perspective it is probably not justified to make people wear masks in all situations," he said.

"Victorians have shown how reasonable and responsible they are. This is one of those situations I feel we can trust Victorians."

A Department of Health and Human Services spokeswoman said masks "have been and remain" vital to "suppressing the transmission of coronavirus".

"As restrictions ease and movement increases face masks are even more important. Advice on face masks continues to be guided by public health experts," she said.

Western Victoria MP Bev McAthur, who does not have health credentials, went further in Victoria's upper house on Thursday and demanded masks become voluntary statewide.

"I don't believe it is right that governments continue to control people's lives," she said.

But Victorian Chief Health Officer Brett Sutton told reporters on Friday that mask-wearing helped keep the chances of a third wave "minimal".

"The mask-wearing is part of that," he said.

It came as the United States' top infectious disease expert Dr Anthony Fauci praised Victoria's mask wearing efforts this week and lamented that the issue had become politicised in the US.

"I really wish that we could transplant that kind of mentality here, because masks in the United States have almost become a political statement," he told a University of Melbourne virtual panel.

Have you signed up to The Standard's daily newsletter and breaking news emails? You can register below and make sure you are up to date with everything that's happening in the south-west.