Melbourne joined again Sydney and Brisbane in Lockdown as Delta Spreads in Australia

Melbourne joined again  Sydney and Brisbane in lockdown less than one week after removing the lockdown after the discovery of new cases of the delta variant of the coronavirus in Victoria. Premier Daniel Andrews announced a snap seven-day lockdown yesterday, with the stay-at-home order coming into effect at 8pm last night.

NSW records 291 new local COVID-19 cases, Victoria records four new cases as state’s sixth lockdown begins, Queensland records 10 new local cases.

NSW has recorded  291 new local COVID-19 cases , the highest number of cases ever recorded in the state within a 24-hour period. It comes after 262 were revealed yesterday, along with five new deaths linked to the outbreak.

NSW Premiere Ms Gladys Berejiklian has made the announcement and  grim admission regarding NSW's future as the Delta crisis rages on.

"We know that, given where the numbers are, given the experience of Delta overseas, we now have to live with Delta one way or another, and that is pretty obvious," she said.

At least 96 of the cases were in the community for their some of their infectious period. The isolation status of 104 cases remains under investigation.

Meanwhile health expert are saying that Sydney's lockdown is "not going to end" on August 28, and  will likely remain until Christmas.

Professor of Epidemiology Tony Blakely has delivered a crushing verdict on Sydney's lockdown.

When asked by ABC News Breakfast co-host Michael Rowland this morning what the chances were of the city’s lockdown ending at the end of the month as planned, his answer was blunt.

“Zero: It is not going to end,” he said.

“The most likely scenario is the lockdown will continue in some form or other, hopefully a little more relaxed for some months, at least two months until the vaccine coverage is upped.

“I realise for the Sydney listeners I’m not bringing you good news, but good news – Christmas and New Year will hopefully be a lot better, as we get the vaccine coverage right and we haven’t opened up our border internationally.”

NSW Health has confirmed there have been 4610 locally acquired cases reported since June 16, when the first case in this recent outbreak was reported. There are currently 304 Covid-19 cases admitted to hospital, with 50 people in intensive care, 22 of whom require ventilation.

Queensland has recorded 10 cases of coronavirus in the community in the past 24 hours, Deputy Premier Steven Miles says.

"We need to continue to see low case numbers all linked, declining infectious days in the community and a high rate of testing," he said.

Mr Miles said it was too soon to say whether the lockdown would end as planned on Sunday afternoon.

Queenslanders might have to wear masks through to Christmas, Chief Health Officer Dr Jeanette Young has warned.

Victorians have been warned to expect a "bumpy' few months as the state records six new locally acquired cases, including two infections that were announced yesterday. Of those, two are in ICU and both are on ventilators.

Victorians have been warned they are in a very "precarious" position as the state's two new Covid-19 clusters continue to grow.

Health Minister Martin Foley has warned Victorians not to be complacent as its sixth COVID-19 lockdown gets underway.

"Victoria remains in a precarious situation," he said.

The Delta variant was presenting a fresh challenge to health authorities due to the speed of spread and its highly infectious nature.

There are now 72 active cases of COVID-19 in Victoria, the "majority" of which are from the previous community outbreak, Victoria's COVID Response Commander Jeroen Weimar said.

He warned that health authorities expect exposure sites start to spread across wider Melbourne and potentially regional Victoria, given the latest positive cases.

Health Minister Martin Foley said lockdowns will continue to be the main tool in fighting Covid-19 outbreaks until vaccination rates are high enough.

"Nobody likes lockdowns. But as we've now established, they work. They're one of our major tools in our public health response, and until such time as we have the levels of 70 to 80 per cent vaccinations, they're going to continue to be a part of that tool kit," he said.

"We can't rule out their future use, but at the moment, we're simply focussed on getting ahead of this particular outbreak and avoiding the kind of catastrophe that Sydney and NSW are enduring at the moment."