South Australia has recorded no new coronavirus cases for the second straight day following a two-day blitz that tested 5209 people.

The state’s premier Steven Marshall praised his residents for their commitment to stopping the spread of the deadly virus by complying with strict lockdown laws.

Seven people in South Australia are in hospital and one is in ICU. A 68-year-old man remains critical.

There have been 435 cases in South Australia and 81 remain active.

“We are very much buoyed by (these results),” South Australia Deputy Chief Public Health Officer Michael Cusack said.

“If you cast your mind back two weeks we received 30 per day and numbers were on the rise.

“With the restrictions that have been brought in and particularly the border restrictions, we’ve been controlling the influx and we have managed to get control of it, but it’s in the coming days and weeks if we have really got control.”

Four cases unlinked

There are just four cases in South Australia where doctors cannot establish a link to another infected person.

The state has conducted 41,000 tests total which is 2.5 per cent of the population.

Four people have died.

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Australia on top

Australia has been largely successful in “flattening the curve” since Prime Minister Scott Morrison introduced strict social gathering policy on March 16.

The country has one of the most extensive testing regimes in the world.

There have been more than 6500 coronavirus cases and 70 deaths in Australia which has so far avoided a disaster like the ones unfolding in Europe and the US.

South Australia has recorded no new coronavirus cases for the second straight day following a blitz that tested more than 4000 people. Credit: Lynne Sladky / AP

However, Morrison warned against complacency and said restrictions would remain in place for at least another four weeks.

The prime minister said Australia needs to meet three criteria before the National Cabinet will consider lifting the country’s coronavirus restrictions.

Refined testing regimes, tracing capabilities and response capabilities at a local level were among the criteria needed to be met before Australia reached “the road out” of the COVID-19 pandemic.

In the video below: Little known symptoms of COVID-19