NSW Chief Health Officer Dr Kerry Chant said authorities were struggling to pin down the source of the new cluster and expected more cases would be detected in coming days.
Fearful that New Year’s Eve activities will spread the virus further, the government announced a reduction in the number of people allowed at outdoor gatherings from 50 to 30.
Senior ministers are concerned that people will instead host parties at home, with one warning that “it will be impossible to police how many people are inside homes”.
Premier Gladys Berejiklian said the new restrictions were in place “until further notice”.
“We don’t want New Year’s Eve to be the cause of a super-spreader [event],” Ms Berejiklian said.
“It only takes one person in [a] family gathering to give it to everybody else in the family.”
Health authorities have so far identified 34 close contacts of the Croydon cluster after extended family held pre-Christmas gatherings over several days across different parts of Sydney.
As of late Wednesday, 8792 permits had been downloaded for access to the CBD’s so-called green zone but there is now more concern about house parties than people converging on the city.
Customer Service Minister Victor Dominello, who has had a major role in the COVID-19 response, said “very few people” were heading into the CBD to celebrate compared to previous years.
“The health advice suggests that gatherings in the home pose a higher risk,” Mr Dominello said.
“Restaurants and cafes doing the right thing with COVID-safe practices backed up with a team of inspectors are more controlled environments.”
Despite the increase in cases outside the northern beaches and predictions of more infections to come, Ms Berejiklian said the third Test match at the Sydney Cricket Ground was safe to proceed.
“The best health advice tells us outdoor, ticketed, seated events are safer than household gatherings, and that’s just a fact,” she said.
“The science and the data tells us the greatest chance of you getting the virus is from somebody you know in a household setting or indoor environment.”
However, the decision to allow the Test to go ahead has also been criticised, with infectious disease expert Raina MacIntyre warning that it would be held a during critical time of the outbreak.
Professor MacIntyre, an epidemiologist at the Kirby Institute, said Sydney was “experiencing the largest community epidemic of the pandemic to date”.
She said the Test could go ahead, but it should be without spectators.
“My prediction is the greatest danger time for Sydney will be from January 6 to 14. This is because New Year’s Eve could be a bigger risk than Christmas,” Professor MacIntyre wrote in the Herald.
“A Test match starting on January 7 in the midst of a surge in cases, would be a risk.”
Australia’s chief medical officer Paul Kelly said would not take his own family to the Sydney Test.
“Their [is] vulnerability and so there is risk,” Professor Kelly, a self-confessed “cricket tragic”, said.
The event could go ahead with COVID safety protocols and masks for people younger than his elderly parents, Professor Kelly said, but the risk profile could change.
“The start date is January 7 and nine days is very long in COVID time,” Professor Kelly said.
The SCG will not close its doors unless there is a Melbourne-like breakout, Cricket Australia has said. “Fifty per cent (capacity) is a baseline but we will be working over coming days to see if we can get more,’’ Cricket Australia interim chief executive Nick Hockley said. ‘‘Obviously, safety is the priority.’’
with Josh Dye, Andrew Wu
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Alexandra Smith is the State Political Editor of The Sydney Morning Herald.
Kate Aubusson is Health Editor of The Sydney Morning Herald.