NSW Health is asking anyone who worked at the hotels on these dates — not others who attended — to get tested and self-isolate.
Anyone who travelled during specified times by train from Minto to Central and by light rail from Central to Darling Harbour between November 27 and November 30 should get tested immediately and self-isolate,until further advised by NSW Health.
Chief Health Officer Dr Kerry Chant said the source of the new infection remains under investigation and urgent genome sequencing will determine within 48 hours whether the infection acquired in the community or through the hotel complex.
"At the moment there isn't a smoking gun in how we'd say the transmission happened,"she said.
The woman was tested on Wednesday and Dr Chant said it was good news that the"highest risk people"– her five household contacts – have returned a negative test. They will all isolate for 14 days.
Dr Chant also said the woman wore a mask while on public transport.
The Premier said it would not be fair to prevent hotel quarantine workers from working several jobs or socialising after hours.
"They have a life outside their jobs,"Ms Berejiklian said.
NSW Labor health spokesman Ryan Park said the government should ensure hotel quarantine workers are given full-time work so they are not working at multiple sites across the city.
Earlier,Health Minister Brad Hazzard downplayed the seriousness of the positive case as he backed the state's"gold standard"contact tracers and health authorities.
"I can't say that I'm overly fussed about it,"he said.
"In the middle of a worldwide pandemic it's a rollercoaster,you've got to expect that we will have more cases from time to time."
There were nine cases recorded in hotel quarantine to 8pm on Wednesday. The positive local case will show up in Friday’s numbers because it was diagnosed after 8pm.
Western Australia'cautious'ahead of planned border reopening
Western Australian Premier Mark McGowan said he expected a decision would be made over the weekend as to whether the new case will delay his state's planned reopening to NSW on Tuesday.
Mr McGowan said his public health team was seeking further advice from NSW Health on the circumstances of the case,noting the woman both worked in a quarantine hotel and lived in south-west Sydney,a site of previous community transmission.
"We'll see whether or not this further spread in NSW before we make a final decision on what happens in terms of the border,"he said on Thursday afternoon,adding that the case indicated it was right for his state to be"cautious"in its reopening.
"I realise this is very disruptive to many people,and very problematic to many people because they don't know what's happening. But at the same time,we have to make decisions that are based upon health advice and based upon the safety of the state,"he said.
Western Australia had been waiting for both Victoria and NSW to reach 28 days without a community case to reopen its border. Victoria achieved the milestone on the weekend,and NSW was due to reach it on Saturday before this case was detected.
Mr McGowan would not deny a delay to the NSW border reopening would affect those wanting to travel to Western Australia from Victoria. Western Australia had planned to reopen to both states on Tuesday.
Queensland Health Minister Steven Miles said he hadno plans to close his state's border to NSW.
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