NSW has announced eight new locally acquired coronavirus cases as known daily infections fell for the second consecutive day.
All but one of Tuesday’s cases are linked to the Avalon cluster, which now stands at 90.
Premier Gladys Berejiklian said the eighth case is under investigation.
The case is a Western Sydney nurse who had moved positive cases in quarantine, and health authorities believe it could be acquired from overseas and yet another leak of the virus from the quarantine system.
That person’s infection has since led to one more work-related case, which was reported after Monday’s 8pm cut-off of the reporting period, and will be included in Wednesday’s numbers.
Ms Berejiklian said authorities were still “concerned” as the number of venues in greater Sydney that have been visited by positive cases continues to grow.
So far, five COVID-19 cases have been linked to Turramurra Salon for Hair and two cases to the Rose of Australia hotel in Erskineville.
Chief Health Officer Dr Kerry Chant said there were also two cases in the upper North Shore, to the west of the Northern Beaches, linked to the Avalon cases, with residents in Berowra, Cowan, Berowra Heights, Hornsby Heights, Mount Colah, Mount Ku-ring-gai, Asquith and a part of Hornsby to be on high alert for signs of the virus.
When pressed on whether the latest apparent leak from quarantine suggested changes needed to be made to the program, Dr Chant said investigations were underway as to whether a breach had occurred.
“Sometimes [breaches] are inadvertent,” she said.
“Sometimes a patient will take off a mask, sometimes a patient doesn't tolerate wearing a mask at a particular point in time.
“There are always a number of elements. I don't want to speculate until we have the genome sequencing.”
Leaks will continue to happen, CHO warns
Dr Chant said it was impossible to prevent transmission entirely when running such programs.
“I don't think any system can ever guarantee that we won't have transmission events. I think it's inevitable that these issues will arise,” she said.
Last week a shuttle bus driver transporting air crew tested positive while at the beginning of December a cleaner contracted the virus from a hotel quarantine facility in Sydney CBD’s Darling Harbour.
There were more than 44,000 tests processed in the previous 24 hours.
NSW Health announced 15 local cases on Monday and 30 on Sunday.
Christmas decision tomorrow
A decision will be made on gatherings for Christmas day when the NSW government cabinet meets on Wednesday.
"We'll be looking to make a decision tomorrow based on what we know and understand during the day ... on what the future of the situation on the northern beaches, greater Sydney, will be," Ms Berejiklian told reporters.
The Northern Beaches are under lockdown until midnight Wednesday and are not allowed to leave their homes unless for work or education, essential shopping, exercise and care giving or compassionate grounds.
Greater Sydney residents aren’t allowed more than 10 people in their homes until midnight Wednesday.
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