The next wave of COVID transmission may be underway in NSW, new data indicates.
There were 6,941 people diagnosed across the state in the week ending March 4, the latest weekly surveillance report showed, an 8.6 per cent increase over the previous week.
Together with an increase in the number of people with COVID going to emergency departments who needed to be admitted, the numbers were "likely to mark the beginning of new wave in transmission", the report noted.
Alexandra Martiniuk, a public health expert from the University of Sydney, said the uptick in emergency department presentations indicated the case numbers signalled a true increase.
"What you can see is an aberration where maybe more people got tested. But that is probably reflecting a true increase when you see also an increased bump up in emergency department presentations," she said.
There were 128 people who presented to emergency departments with COVID who needed to be admitted, up from 107 admissions the previous week.
Professor Martiniuk said the small numbers of emergency department admissions could jump around, so another rise next week would be needed to confirm a new wave was underway.
There have been four waves of COVID in NSW since Omicron became the dominant variant at the beginning of 2022, each one smaller than the last.
Professor Martiniuk said high vaccination rates were contributing to the smaller number of cases in successive waves.
"The other thing is that now we have less of a COVID-naive population. So most people have had at least one COVID infection. And so that does protect," she said.
She said all the new sub-variants were in the Omicron family, though experts were watching for new variants that could cause bigger waves.
"But if we are to keep within that Omicron family the thought is that these waves may stay smaller," she said.
There were 28 COVID deaths reported, down from 48 deaths reported the week before.
