On Tuesday, Victorian Premier Daniel Andrews mentioned the possibility of stage four restrictions.

"I can’t rule out we have further limits placed on people’s movement. I can’t rule that out," he told reporters.

"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. Do the right thing by your family, your community, and every family."

It comes as metropolitan Melbourne is seeing unprecedented levels of community transmission.

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So, what exactly would a stage four lockdown entail?

Since the pandemic began, no Australian state or territory has entered a stage four lockdown - meaning there is no government guide outlining what further measures may include.

New Zealand was in stage four lockdown from March 25, and remained there for 10 weeks. The country achieved substantial success in slowing the spread of COVID-19 under their stage four lockdown, temporarily eliminating the virus from their shores (until overseas travellers returned and re-introduced it).

The Prime Minister has announced New Zealand Covid-19 Alert Levels. Here is a table that explains what they mean. This information will be available on the https://t.co/vEvj37KKdO website shortly. pic.twitter.com/1iW7L75AfY

— National Emergency Management Agency (@NZcivildefence)

Here is what their stage four lockdown looked like:

Other measures may include compulsory mask-wearing, and establishing self-contained zones, which would involve restricting travel within certain suburbs and postcodes.

So, how likely is it that Melbourne could enter stage four restrictions?

Dr Sanjaya Senanayake, an Infectious Diseases Specialist from the Australian National University, told ABC’s7.30on Tuesday that stage four restrictions were "on the table, for sure".

"It means very limited, very restricted movement. It will be mentally challenging for all the residents who are under that stage four lockdown. It will have economic consequences, too...

"We know from the Wuhan experience, though bigger than Melbourne, it took about four weeks for the outbreak to come under control using lockdown measures."

Currently, five million metropolitan Melbourne residents are living under stage three restrictions.

The Victorian Government announced the Stay at Home Directions for metropolitan Melbourne and Mitchell Shire from 11:59pm on Wednesday, July 8, effective for six weeks, until Wednesday, August 19.

Residents have four permissible reasons to leave the house. They are:

Masks are heavily encouraged for Melbournians to wear when outside their home, but are not yet compulsory.

The number of new cases that can be attributed to community transmission in the coming days will be the decider for if the city is placed under a stage four lockdown.

Feature image: Getty.

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