“It is concerning he has transmitted in a cafe and we will look at any information about the proximity they may have had but clearly that gives us a raised level of concern,” Dr Chant said.
Meanwhile, health authorities are also investigating a possible fourth local case in Sydney after a Baulkham Hills man in his 40s tested positive on Wednesday night.
The man had a low viral load with high cycle threshold (CT) values, Dr Chant said.
“High CT values can indicate that you might be beginning to be infectious or it could be an old infection or a false positive,” she said.
Preliminary interviews have not indicated he is linked to any identified exposure sites or venues, she said.
More than 700 people have been tested and are in self-isolation following a number of venues across Sydney’s east and north were identified as possible COVID-19 exposure sites on Wednesday.
There were 23,145 tests reported to 8pm on Wednesday, more than double the previous day’s total of 10,524.
Earlier on Thursday morning, before the third and possible fourth cases were announced, the Premier said she expected testing rates in Sydney’s east to “go through the roof”.
“We can’t be complacent about it, we know that two can become 20 very quickly,” she said.
Mr Hazzard said the fresh local cases were a reminder to get vaccinated.
“We’ve already heard that one 70-year-old lady happened to be in the wrong place at the wrong time and got the virus: that could happen to any one of us,” he said.
Unrelated investigations are also continuing into a possible leak within the Radisson Blu quarantine hotel, in Sydney’s CBD, where recently returned travellers staying in adjacent rooms returned positive COVID-19 tests with the same viral sequence.
Earlier on Thursday morning, opposition health spokesman Ryan Park said it should not be optional for frontline border workers to be vaccinated.
“It beggars belief,” he said on 2GB. “Arguably one of the most high-risk occupations and we have people transporting international flight stewards and staff around the city without being vaccinated in the middle of a pandemic.”
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