NSW has reported 112 new locally acquired cases, the highest number since the start of the latest coronavirus outbreak.
Premier Gladys Berejiklian told reporters at least 34 people were in the community whilst infectious, adding that number needed to be as close to zero as possible before coronavirus restrictions could be eased.
Of the new locally acquired cases, 64 are linked to a known case or cluster – 41 are household contacts and 23 are close contacts – and the source of infection for 48 cases remains under investigation.
Ms Berejiklian said most of the cases were still concentrated in the Canterbury-Bankstown, Liverpool and Fairfield local government areas.
“The vast majority of cases are in the Fairfield Local Government Area. Everybody in Fairfield should be staying at home unless they absolutely have to [leave],” she said.
“That is the message across everywhere in Greater Sydney, but in particular, when large numbers of the virus are circulating in one local government area, we must call that out.
"We need to call that out because that is where the virus is spreading the most. We really want to stress that, even if you regard yourself as an essential worker, especially in the Fairfield Local Government Area, do not leave home if you have symptoms.
"Do not go to work unless you absolutely know that you don't have the virus."
Nine Sydney suburbs of concern
Chief Health Officer Dr Kerry Chant told reporters there were nine suburbs of concern in Sydney's southwest.
The suburbs include Fairfield, Smithfield, Bossley Park, Fairfield Heights, Fairfield West, Wakeley, Bonnyrigg, Glenfield and West Hoxton.
"I want to highlight that we are also seeing cases emerge among young adults in the 18 to 20-year-old age group in the Georges River, Bayside and Sutherland Local Government Areas and they are largely spreading it, again to echo the premier's words, to their closest friends and family," she said.
Dr Chant added there are currently 63 COVID-19 cases admitted to hospital, with 18 people in intensive care, four of whom require ventilation.
Fourteen of those in hospital are aged under 35.
Dr Chant warned the Delta variant of the virus, which is circulating in Greater Sydney, dispelled the notion that the virus will not cause young people to become ill.
In the 24 hours before 8pm, NSW conducted 46,478 tests and administered 11,467 vaccines.
The latest figures come after the state reported 77 new cases on Sunday, with the premier warning it was "highly unlikely" the lockdown in Greater Sydney would end on Friday as planned.
When will Sydney's lockdown end?
Ms Berejiklian said with 34 cases infectious in the community for the entire duration of their illness, they did not have the answer for how long the lockdown in Greater Sydney would last.
She added however there had been a massive drop in mobility in the community and once health authorities can determine the impact of that, then they will be able to have a better idea of when the lockdown will end.
"Our priority is always about what life looks like once we get out of the lockdown and getting out of the lockdown as quickly as we can and providing less stress for our citizens as quickly as we can," she told reporters.
"I can't stress enough that is up to all of us. We have a collective responsibility to make sure we all do the right thing – we don't cut corners and it only takes a few people to do the wrong thing at the same time for us to be locked down for longer than we want to or longer than we need to."
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