A 70-year-old woman who attended the same café as a coronavirus-infected Sydney man has also tested positive.
The woman attended the Belle Café in Vaucluse, one of the many exposure sites announced yesterday.
The woman is the third person in the past 24 hours to test positive for the virus in Sydney.
The first two, an airport driver and his wife, were announced yesterday.
The driver’s other close contacts, including family members and co-workers, have all tested negative.
A man in his 40s in the Baulkham Hills area has also tested positive, but NSW Premier Gladys Berejiklian said it was possible that case was a false positive or a historic case.
She did not announce any new restrictions, but implored people to be careful and to socially distance.
“If you’re in the eastern suburbs, unless you absolutely have to attend a large gathering, unless you absolutely have to engage in activities of a social nature in the next few days, we ask everybody to refrain from that, to be extra careful, to make sure you hand sanitise and socially distance,” Ms Berejiklian said.
“If you’re catching public transport, we recommend people wear a mask.”
She urged people to be “extra cautious”.
“Assume that everybody you’re in contact with has the virus and assume you have the virus yourself,” she said.
“Socially distance. Make sure you hand sanitise. Make sure you don’t engage in any activity with large gatherings unless you absolutely have to.”
Chief Health Officer Kerry Chant said the limousine driver had the Delta strain of the virus, a particularly infectious variant.
“This strain does not match anything that’s been uploaded in Australia at this time,” Dr Chant said.
“It does match perfectly a sequence that’s been uploaded from the US and so that fits with that plausible hypothesis.”
She said the Baulkham Hills man had no connection to any of the exposure sites announced yesterday.
“The gentleman had high CT values and for us, that means a low viral load,” she 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 thanked 450 members of the public who came forward to self-declare they had been at an exposure site.
Health Minister Brad Hazzard noted that 3.8 million people have died from coronavirus worldwide.
“Being slack about what the health authorities ask you to do is just inexcusable,” he said.
“We have to make sure that we all follow the rules.”
He urged people to get vaccinated “as soon as your turn comes”.
“One 70-year-old lady happened to be in the wrong place at the wrong time and got the virus,” he said.
“That could happen to any one of us.”
Ms Berejiklian said police were investigating how the limousine driver was able to pick up overseas arrivals without being vaccinated.
“But there are strict guidelines in what workers, including limousine drivers, are obligated to do every day,” she said.
“Anyone who is not vaccinated doesn’t work directly around the quarantine system.”
Dr Chant said health officials believe the limousine driver was infectious from June 11.
NSW Health is investigating several scenarios as to how the driver contracted COVID-19.
Dr Chant said the “obvious hypothesis” is the man transported overseas flight crew who subsequently tested positive despite testing negative on arrival into the country.
“If that is the possible hypothesis, he has not been infectious before the 11th,” she said.
“Obviously, we are still putting the pieces of the puzzle together and testing in the community helps us.”