Key Points
- Highly transmissible COVID subvariant KP.2, which quickly spread through the US, was recently detected in Australia.
- Experts said that, while most Australians don't face much risk, vulnerable populations should remain cautious.
- The public health advice remains the same: get vaccinated, be vigilant and stay home if symptoms appear.
A family of highly transmissible COVID-19 subvariants has been detected in Australia, as experts continue to urge people to get vaccinated against the virus.
The most notable of the new subvariants is KP.2, which recently accounted for about 25 per cent of new sequenced cases in the United States and belongs to a subset of COVID-19 variants that scientists have dubbed 'FLiRT'.
The label derives from the technical names of the different variants’ mutations, one of which includes the letters F and L and another of which includes the letters R and T.
It’s understood that KP.2 was recently detected in NSW and Victoria, and at least one expert said it's "taking off" in Australia. Here’s what we know.
What is the new COVID-19 variant?
KP.2 is an Omicron descendant that closely resembles JN.1: a variant that rose to prominence in late 2023 and became the dominant form of COVID-19 in Australia.
The World Health Organization in December 2023, and in January the Royal Australian College of General Practitioners described it as a "significant" strain which, due to its distinctive characteristics, signalled "a new phase of the pandemic".
Experts have described KP.2 as being very similar to JN.1, while suggesting that slight differences in the latter variant’s spike protein might make it better at evading our immune system and therefore more infectious.
Are the FLiRT variants cause for concern?
Professor Adrian Esterman, chair of biostatistics and epidemiology at the University of South Australia, predicted that JN.1 would soon disappear in Australia and "very, very quickly" be replaced by the new FLiRT subvariants that are "taking off".
However, he noted that KP.2 was "not a major issue" for most of the country’s adult population.
"From the evidence that we know so far, it's pretty similar to JN.1 in terms of the severity of infection, in terms of the types of symptoms — it’s much of the same," Esterman told SBS News.
"Most adults, really and truly, there's nothing to worry about. If they're careful, then they'll get an updated booster shot if they haven't had one in the last 12 months… If they do get infected, chances are [it will be] just like a nasty flu, and for many people be no symptoms at all."
Esterman noted, however, that the new variant does pose a serious threat to vulnerable populations, such as elderly people or those with health conditions like diabetes, who could get "severely ill" from the virus.
"Now's the time when vulnerable people… [need to] make sure we're up to date with that booster," he said – noting that of all people age 75 and over in Australia, only 40 per cent have had a booster shot in the last six months.
"So basically 60 per cent of the very elderly population is unprotected," he said.
What should the general population do?
There is much that remains unknown about the new FLiRT variants, and which will likely only come to light in the next few months as Australia enters winter — when experts expect cases to rise.
Paul Griffin, an infectious disease physician and clinical microbiologist at the University of Queensland, suggested that the majority of people don’t need to worry about staying abreast of every variant or subvariant that emerges.
"For most people, they don't need to basically pay attention to the fact that there's new subvariants, or what they're called or what the mutations are," he said. "I think that's something that we [experts] should follow, and make sure that our advice matches up with what's happening."
That advice, Griffin added, remains largely unchanged. People should stay up-to-date with vaccinations and vaccine recommendations, stay home and get tested if they feel unwell and take whatever measures are necessary to protect vulnerable people from potentially catching the virus.
"They're things that we need to keep reiterating because they’re going to remain important for the foreseeable future," Griffin told SBS News.
"We know that COVID has changed a lot over the journey and continues to do so … and that raises concern about immune evasion or where protection from vaccination and past infection might decline. But there's nothing to suggest that (this new strain is) any more nasty, more virulent or infectious," he said.
"It just means that it highlights the message that we've been trying to get out there for a while: that we need people to remain vigilant to a degree and particularly keep up to date with vaccination."