Child among new NSW coronavirus cases amid concern over potential for Sydney CBD cluster

The Northern Beaches cluster now exceeds 100 with a child expected to be among the new cases reported in the last 24 hours.

A man receives a COVID-19 test at a drive-through testing station in Sydney. Source: AAP

A child who tested positive for COVID-19 is expected to be among new virus cases announced in NSW on Boxing Day, as health authorities battle to contain the Sydney outbreak.

Seven new cases linked to the city's northern beaches outbreak were announced on Christmas Day as Australians gathered for COVID-safe celebrations.

NSW Health said the Avalon cluster had reached 108 cases. A child who tested positive after the 8pm Thursday cut-off will be among the new coronavirus cases announced on Saturday.

Health authorities are also concerned about the possibility of another Sydney CBD outbreak emerging, with three cases connected to the Paragon Hotel Sports Bar at Circular Quay.

NSW Premier Gladys Berejikilian warned people to avoid the CBD if they could on Boxing Day, and if they could not to wear a mask.

"We'd prefer people did not go to the CBD because then you have people from all over Sydney coming to one location, and it only takes one or two cases for it to then spread everywhere else," she said.

NSW Health also issued a new alert on Friday afternoon flagging infection risks at 10 Sydney locations, four buses and a regional flight.

In Queensland, a second crew member on a superyacht near Cairns tested positive for COVID-19.

A man in his 30s who arrived on the vessel from the Maldives on Monday tested positive on Friday, after a female crew member in her 20s had earlier been confirmed as infected.

Some 14 guests and crew have been directed to hotel quarantine while six other crew members remain on the vessel.

Another new Queensland COVID-19 case is in hotel quarantine while two returned travellers from overseas tested positive in South Australia and one in Western Australia.

Fifteen new cases were reported in the country in total on Christmas Day.

People in Australia must stay at least 1.5 metres away from others. Check your jurisdiction's restrictions on gathering limits. If you are experiencing cold or flu symptoms, stay home and arrange a test by calling your doctor or contact the Coronavirus Health Information Hotline on 1800 020 080.

News and information is available in 63 languages at sbs.com.au/coronavirus.

Please check the relevant guidelines for your state or territory: NSW, Victoria, Queensland, Western Australia, South Australia, Northern Territory, ACT, Tasmania.