SA locks down, Victoria extends and NSW reports 78 new cases

South Australia is going into lockdown tonight as Victoria extends its own lockdown and new cases are reported in several Australian states.

NSW recorded 78 new locally acquired cases of Covid-19 in the 24 hours to 8pm yesterday, with Premier Gladys Berejiklian saying 21 were infectious while in the community and eight were in isolation for part of their infectious period.

The isolation status of 12 cases remains under investigation.

Some 63,000 tests were done in the past day and they picked up cases in people who were not symptomatic, something the premier said was good news.

However, NSW Police Deputy Commissioner Gary Worboys said officers yesterday busted an office party after stumbling across a gathering while patrolling George Street in Sydney CBD.

One attendee was found passed out on the floor.

"Seven people in a small office suite. Birthday cake, alcoholic drinks, birthday food, and a person passed out on the floor.

"No evidence of any mask wearing, no good reason to be in that office suite, no good reason to have a party."

He said seven fines were issued for breaching public health orders.

Chief health officer Kerry Chant said a woman who died yesterday after contracting Covid-19 was offered care and support beforehand.

"That family were offered care, and were offered transport to alternate facility to support them with their isolation and care," she said.

"They made the decision to stay at home."