Meet FLuQE: the new COVID-19 variant wreaking havoc on Aussies this winter

The 'FLiRT' sublineages, including KP.2 and KP.3, stem from JN.1, which dominated infections early this year.

KP.2 made up around 50 per cent of COVID-19 infections in NSW up until May 4, according to NSW Health.

The Victorian Department of Health found KP.3 and other JN.1 variants were in wastewater in "increasing abundance" in their May 17 report.

The World Health Organisation classified these subvariants as "circulating variants under monitoring".

But KP.3, nicknamed FLuQE, has now become the fastest-growing member of the family.

It has an extra mutation researchers say which makes it more infectious.

And it's that extra mutation that has led to its own catchy subvariant nickname.

It is now the dominant strain in several countries including Australia.

University of New South Wales associate professor Stuart Turville told ACM FLuQE has a "competitive edge" because of two main factors.

"It has the ability to navigate antibodies better than other variants and it also is more efficient in the way it can engage entry factors which allows it to stick to the cell," he said.

But Prof Turville noted it was not a "seismic change" to COVID-19 variants.

"The way that I see it it, is an iterative change, this isn't a jump, it is a virus month-by-month small changes in its outer coat ( the spike) and it is doing it to navigate, to be more competitive," he said.

Prof Turville said "vulnerable populations such as the elderly" should take precautions.

In the week ending June 22 Australia's most populous state NSW recorded 4850 COVID-19 cases.

That's a 3 per cent increase in COVID-19 notifications on top of an increase of 38 per cent in influenza notifications and an increase of 6 per cent in RSV notifications.

Western Sydney has the most cases (784 cases), followed by northern Sydney (640 cases) and then south western Sydney (627 cases).

The worst regional area was Hunter New England (528 cases) followed by Illawarra Shoalhaven (265 cases) and then the Central Coast (218 cases).

In the ACT there were 854 infections in June with a person in their 40s dying after a positive test.

And in Victoria where COVID-19 monitoring appears less thorough KP.3 has been increasing in Victorian wastewater at about 42 per cent in the most recent samples.