* NSW recorded 177 new COVID-19 cases and a death on Wednesday, as Premier Gladys Berejiklian confirmed lockdown will be extended until at least August 28 for Greater Sydney, the Central Coast, the Blue Mountains, Wollongong and Shellharbour.

* Some restrictions have changed, including the introduction of a singles bubble for those who live alone, and the return of HSC students to the classroom on August 16.

* The local government areas of Parramatta, Campbelltown and Georges River have also joined a growing list of areas where only authorised workers can leave their council area.

* Victorian authorities are racing to find the source of a new local coronavirus case on the state's first day out of lockdown. The new case, one of nine recorded on Wednesday, is a traffic controller at the Moonee Valley racecourse drive-through testing centre, where he worked at least two days while infectious.

* The federal government announced coronavirus disaster payments will rise to $750 a week for workers who lose employment because of lockdowns, with the new rate mirroring the original JobKeeper wage subsidy.

* Businesses hit hard by Victoria's latest lockdown and ongoing restrictions will also be able to access a series of grants as part of a $400 million support package jointly funded by the federal and state government.

* SA has reported no new virus cases for the second day in a row as it ends its week-long lockdown, but the state will continue to take a tough stance on locals returning from NSW.

* The risk of a COVID-19 outbreak in Queensland is escalating after another 20 cases were recorded in the state. One of the cases is a man who has been infectious in Brisbane for six days after completing hotel quarantine. Another 19 people with coronavirus are contained on a ship offshore.

* A further six crew members aboard the Darya Krishna ship docked in WA's Fremantle Harbour have tested positive for coronavirus but will be included in Thursday's figures.

AUSTRALIAN VACCINATION NUMBERS:

* There have been 11,593,766 doses administered in the national COVID-19 vaccination rollout up to Tuesday, including 196,982 in the previous 24 hours.

* Of the total, 6,532,809 have been administered by the Commonwealth (an increase of 118,241 in the previous 24 hours).

* 6,024,054 have been issued in primary care (+114,565) and 508,755 in aged and disability facilities (+3676).

* 5,060,957 have been administered by the states and territories, including 78,741 in the previous 24 hours.

* 1,572,283 have been administered in Victoria (+19,178), 1,395,881 in NSW (+25,375), 875,187 in Queensland (+12,789), 471,771 in Western Australia (+9727), 372,042 in South Australia (+6228), 157,548 in Tasmania (+2056), 129,766 in the ACT (+2328) and 86,479 in the NT (+1060)

AUSTRALIAN CORONAVIRUS NUMBERS:

* Australia reported 186 local cases on Wednesday, July 28.

* There were 20 new overseas-acquired cases, 19 contained on a ship off Queensland's shores and a crew member from a container vessel docked in WA's Fremantle Harbour. (The six additional crew members will be included in Thursday's official figures).

* The national death toll is 921: Victoria 820, NSW 67, Tasmania 13, WA 9, Queensland 7, SA 4, ACT 3. (Two Queensland residents who died in NSW have been included in the official tolls of both states).

GLOBAL CORONAVIRUS NUMBERS:

* Cases: at least 195,329,792

* Deaths: at least 4,177,400

* Vaccine doses administered: at least 3,924,352,476

Data current as at 16:30 AEST on July 28, taking in federal and state/territory government updates and Johns Hopkins Coronavirus Resource Centre figures.

Australian Associated Press