Are stage 4 coronavirus lockdown restrictions coming to Victoria and what are they?

As Victoria grapples with more than 200 new Covid-19 cases each day, questions are being asked of the premier, Daniel Andrews, and the chief health officer, Prof Brett Sutton, about whether tougher restrictions – or “stage 4” lockdown measures – are on the cards.

There is no definition of what stage four may involve given no one can predict what case numbers may look like in a month, let alone a week’s time, and therefore what responses may be necessary.

This lack of clarity has prompted plenty of speculation about what might lie ahead. Scam text messages with false information have fuelled fears about what a stage four lockdown could entail.

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New Zealand has more clearly outlined its stages of lockdown, but the strategy there has been elimination, as opposed to Australia’s goal of suppression and containment.

Stage four restrictions ended in New Zealand at the end of April. They involved cancelling events and closing all public venues, closing all educational facilities, and closing most businesses including fruit shops, butchers and bakeries.

Are tougher restrictions a possibility in Victoria?

Yes. Sutton and Andrews have made it clear their goal is to maintain stage three restrictions, under which Victorians can only leave their homes to shop for food and essential items, provide care, do outdoor exercise and work or study. They are in place for a period of six weeks.

However, Andrews said whether tougher measures could be brought in before then depends on the behaviour of individuals over the coming days and weeks.

“I can’t rule out we have further limits placed on people’s movement,” Andrews said on Wednesday.

“As I always said, if we’re planning for it, we’ll share it with the community. That’s in the hands of hard-working Victorians. If you don’t want a stage four, if you don’t want the lockdown to last a moment longer, then please follow the rules.” The premier provided no detail on what additional restrictions may be considered.

Meanwhile, Sutton said “any consideration about what stage four might look like” would be based on epidemiology. That means looking at whether specific postcodes or groups of people are more affected than others and responding accordingly.

He also said earlier in the week “we would do the minimum required because we know how much of an imposition it is on businesses and people’s lives”.

“But if it’s required to reduce transmission, then it has to be in play,” Sutton added.

What do the experts say about stage four?

A professor of infectious diseases and doctor at Canberra hospital, Prof Peter Collignon, said given the most effective measures to combat the virus were physical distancing, hygiene practices, contact tracing, staying home when unwell and getting tested, it was not clear what benefit any further restrictions may have given elimination was not the goal.

“I’m not sure that harsher restrictions are more effective,” he said. “Victoria had harsher restrictions than the rest of Australia last time but were less successful than Canberra, Brisbane, Adelaide or Perth.”

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Collignon said those cities had achieved similar outcomes to New Zealand without going quite so far despite larger city populations than New Zealand.

Even Sydney has been much more successful than Melbourne, Collignon noted. California has again had an outbreak despite previous hard restrictions.

“You do need restrictions in place, but very harsh ones may not be effective,” he said. This may also be because people could begin to suffer from restriction fatigue.

Associate Prof Hassan Vally, a public health expert and epidemiologist with La Trobe University, said the six-week period for the current Victorian measures was sensible and would give health authorities enough time to collect data to make informed decisions about the next steps – whether that was increasing or reducing restrictions.

“What we don’t want to do is to go down this path and to lock down for too short a time so that we don’t get on top of transmissions, and of course we don’t want to lock down any more time than is necessary,” he said. “This seems like a sensible length of time to get on top of transmissions.”

What is the federal government saying?

The health minister, Greg Hunt, urged people to “be very cautious about rumours on social media” regarding increased restrictions.

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“More generally though, our goal as a country, and whether it’s as a Victorian or a Melburnian, is to avoid having to go to higher levels of lockdown,” Hunt said.

“We know this level has enormous human and economic consequences, whether it’s a single parent in a small flat with young kids, whether it’s a worker who’s been stood down from a particular form of hospitality, a cafe, or a restaurant, whether it’s the owner of a beautician salon.

“All of these people are doing it tough as it is already. So higher levels of lockdown would mean even greater hardship for individuals, mental health, social isolation, the elderly who’ll be isolated. Our goal is to avoid that.”

The prime minister, Scott Morrison, echoed the health minister, telling radio station Triple M on Wednesday: “You don’t go to the extremes on any of this stuff, you just keep going down the middle, and that’s where you make the most ground. Your protection against the virus is not shutting things down all the time.”