Aussies are back in lockdown prison

The state of South Australia announced a six-day "circuit-breaker" lockdown for its nearly two million people on Wednesday to contain a sudden coronavirus cluster in its capital city that ended a months-long streak of no infections.

Schools, restaurants and factories were told to close at midnight while stay-at-home orders were issued for residents across the state.

It came as two new cases were linked to a cluster that emerged from an Adelaide hotel used to quarantine travellers from overseas, taking the outbreak to 22 cases.

Weddings and funerals will be banned and mask-wearing in public made mandatory in the state, which had not recorded a significant outbreak since April.

"We are going hard and we are going early," state premier Steven Marshall said. "Time is of the essence and we must act swiftly and decisively. We cannot wait to see how bad this becomes."

The approach stands in stark contrast to the United States -- where some politicians are refusing to implement virus measures even as case numbers surge -- or Europe, where lockdowns were introduced only after infections spiralled.

South Australians have been told to only leave their homes for essential work, to buy groceries or for health reasons. The state is the first in Australia to ban outdoor exercise for all residents since the pandemic began.