Health authorities have identified four cases of the Omicron "sub-variant" among recent COVID-19 infections, but believe it is no more severe than its original strain.
Chief health officer Kerry Chant said there was likely more cases of the BA.2 strain, which she described as a "breakaway" from Omicron — or BA.1.
Dr Chant said data from overseas suggests the sub-variant may have a growth advantage over its predecessor.
"We know that it is circulating in countries and we have seen it grow significantly. So for instance in Denmark, it is now the dominant [strain] over BA.1 and we are seeing its prevalence," she said.
"But at the moment we don't see that it is presenting anything different clinically in terms of the severity or its response to vaccine but will obviously be watchful, monitor the situation closely."
NSW recorded another 52 COVID-19 deaths in the 24 hours to 8pm on Saturday.
A total of 2,663 people with the virus are in the state's hospitals, of which 182 are in ICU and 73 require ventilation.
Dr Chant said 33 men and 19 women — with the youngest being in their 60s and the eldest more than 100 — died in the latest reporting period.
Of the new deaths, 31 people were aged care residents.
"And of those 31 people, just two had received booster doses," Dr Chant said. "Twenty had received two doses of vaccine, two and received one dose and seven were not vaccinated."
One man in his 60s who died had received two vaccine does but had significant pre-existing health issues, she said.
From February 1, NSW Health will change its reporting period cut-off time to 4pm — instead of 8pm — signalling a shift in the work of experts.
Dr Chant said it would put epidemiologists, surveillance officers and data analysts, who had been working day and night throughout the pandemic, on a more "sustainable footing".
"This will also allow them to focus on some additional work in epidemiology, reports and provide more granular detail that will support the community as we move forward with our COVID response," she said.
There were 13,524 new cases recorded in the reporting period, of which 6,032 were from positive rapid antigen tests (RAT) and 7,492 were from PCR swabs.
Since RAT reporting began on January 13, there has now been more than 247,000 self-reported positive cases.
The state's booster shot rate has risen to 38.8 per cent of eligible people, while 37.4 per cent of children aged five to 11 have now received their first vaccine dose.
Premier Dominic Perrottet offered his condolences to the families of lost loved ones and urged the community to book in their boosters.
"It is key to keeping you, your friends and your family safe," he said.
The double-dose rate for children aged 12 to 16 is now at 78.5 per cent, while 83.2 per cent have had one jab.
For the over-16 age group, 94 per cent have had two doses and 95.4 per cent one dose.
