South Australia today recorded zero new cases of coronavirus, one day after the state announced a six-day “circuit breaker” lockdown prompted by a worrying COVID-19 cluster in Adelaide’s north.

Speaking to the media Thursday morning, Chief Public Health Officer Dr Nicole Spurrier confirmed the number of confirmed cases linked to the Parafield cluster remains at 23.

In addition, health authorities are monitoring 17 suspected cases of COVID-19.

Dr Spurrier said as many as 3,200 people identified as close contacts, and close contacts of those close contacts, have been asked to quarantine.

The news comes after nearly 12,000 tests were conducted yesterday.

Despite the encouraging results, Premier Steven Marshall defended the decision to enter a strict six-day lockdown, saying that as many as 1,000 South Australians could be roaming around while unknowingly infected with COVID-19.

“What we do for the next six days will determine if we are able to successfully stare down the threat posed by this outbreak of COVID-19,” Marshall said.

From 12am this morning, the state entered what Marshall called “essentially a stay-at-home order”.

South Australians have been advised to remain at home unless they are seeking essential goods and services. Even then, folks have been advised to observe a once-per-day rule.

Outdoors exercise has been temporarily banned, as have weddings and funerals.

Pubs, cafes, food courts, and takeaway joints have been closed, in addition to all university campuses and schools (vulnerable children and the children of essential workers are excepted).

A mask mandate has also come into place.

Meanwhile, Victorian Premier Daniel Andrews this morning announced the state will make the “difficult decision” to temporarily close its border with South Australia over concerns of viral transmission.

“Victorians have worked too hard and given too much to allow anything to put at risk our goal of reaching COVID Normal by Christmas,” Andrews said in a statement.

“We’ll do whatever it takes to keep Victorians safe.”

A hard border will be established at midnight tonight, with a permit system coming into play at 11.59pm on Saturday.

Until that point, only freight drivers, those with urgent medical or animal welfare needs, or those “authorised by law” will be allowed to cross over.

Victoria today recorded its twentieth consecutive day with no new COVID-19 cases or deaths linked to the virus.

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