The new system will kick in at 4pm Tuesday, and last for up to six months.

It will involve a 14-day isolation period for non-essential travellers including South Australians returning from interstate, but will include exemptions for essential travel to maintain health, the food supply chain, and the State’s economic needs.

Those crossing the border into SA will have to sign documents showing they understand the restrictions and give details of where they will self-quarantine, with police given the power to make spot checks and detain and fine those found in breach.

“I’m ordering the effective closure of our borders to protect the health of South Australians by slowing the spread of the virus,” Premier Steven Marshall said on Sunday.

Exemptions for essential transport will include health workers and medical supplies, patients, relatives and carers as well as emergency services.

Also at 4pm today, Defence Force personnel will set up camps at Northern Territory border checkpoints and provide medical assistance to conduct checks of people entering.

All travellers will go through a controlled checkpoint and must verify their current health status, reason for travel and if they have an exemption.

Although exemptions apply for those who provide goods and essential services, everyone who enters the Territory must complete arrival forms.

Those without an exemption are required to self isolate for 14 days.

From Thursday, Coles will begin a special hour of trade for workers including doctors, nurses, paramedics, hospital workers and firefighters.

Workers will need to be wearing their uniforms, carrying their work ID, or their Australian Health Practitioner Regulation Agency card to access stores when they open at 7am on Tuesdays and Thursdays.

Coles says it’s also in the early stages of rolling out a new priority online shopping service for Australia’s most vulnerable customers, after suspending ordinary online orders last week.

Priority access for health and emergency workers won’t affect existing arrangements for vulnerable and elderly customers.

Those customers will continue to have their own special shopping hour on Mondays, Wednesdays and Fridays.

Coles Group chief executive Steven Cain says it’s important to help healthcare and emergency services workers, who are under enormous strain amid the coronavirus emergency.

The retail giant says it’s currently spending an extra $1 million a week to clean its stores, and increase security at its outlets.

It has also introduced measures to help customers exercise social distancing, including advice for shoppers to stay a trolley length distance away from others.

The competition watchdog will also allowing supermarket rivals to coordinate on supply and logistics so vulnerable consumers aren’t left empty handed amid unprecedented coronavirus panic-buying.

The ACCC announced Tuesday that Coles, Woolworths, Aldi, IGA supplier Metcash and others would be given temporary authorisation to work with each other when liaising with manufacturers, suppliers, and transport and logistics providers to keep their shelves adequately stocked during the pandemic.

“This is essentially due to unnecessary panic buying, and the logistics challenge this presents, rather than an underlying supply problem,” ACCC chair Rod Sims said on Tuesday.

Panic buying has resulted in surging sales at supermarkets in recent weeks but many stores have faced periods without essential items – such as toilet paper and non-perishable foods – being available.

Most outlets have imposed limits on the take home of certain products while others have created special trading hours for the elderly and vulnerable to counter grocery hoarding.

The ACCC said the Department of Home Affairs Supermarket Taskforce approached it with the cooperation proposal on Friday and the interim agreement was put in place on Monday afternoon.

The interim ACCC agreement does not allow supermarkets to agree on retail prices for products.

Grocery retailers, suppliers, manufacturers and transport groups can choose to opt out of any arrangements.

ACCC authorisation provides statutory protection from court action for conduct that might otherwise raise concerns under the competition provisions of the Competition and Consumer Act 2010.

It comes as Australia’s Deputy Chief Medical Officer Paul Kelly says testing criteria for coronavirus will change as a result of sweeping travel bans that have lessened the risk of imported disease.

Current rules require tests for people who fell ill within two weeks of returning from overseas, or had contact with such a person.

But Prof Kelly has indicated a rule change that’s more focused on community transmission, telling the ABC the traveller component would be removed.

“There will be announcements about that over the coming days,” he told the ABC’s Q&A program on Monday night.

Meanwhile, NSW Police Minister David Elliott says a decision to let thousands of passengers leave the Ruby Princess cruise ship and disperse throughout Sydney was a “monumental stuff up”.

At least 50 people from that vessel have the virus.

In Western Australia, police and Australian Border Force officers are on alert to ensure passengers do not leave a cruise ship which has docked at Fremantle Port.

Premier Mark McGowan warned that no one will be allowed ashore as the Magnifica refuelled following its arrival early Tuesday, amid fears at least 250 of more than 1700 passengers are suffering upper respiratory illness.

But ship operator MSC denies any crew or passengers on the ship, which departed Italy in January and is on its way to Dubai, have respiratory or flu-like illnesses.

The government claims the vessel has given inconsistent reports about the health of its passengers.

And Tasmania has banned non-essential visitors from entering the state via the Spirit of Tasmania ferry in tightened coronavirus measures.

Only essential travellers or Tasmanians returning home are allowed to use the TT-Line Bass Strait service, Premier Peter Gutwein announced on Tuesday.

“As from today, if you are travelling to Tasmania and it’s non-essential travel, do not come. Do not get on the TT-Line,” he said.

“What we will do is turn you around and ask you to go back.”

-with AAP

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