FLiRT-ing with bird flu – the latest on both viruses

FLiRT: it’s a catchy name for a mutation of a virus that originally left a wake of devastation and destruction in its path, caused global lockdowns and was universally feared.

After working through the Greek alphabet to name variants of the coronavirus disease (COVID-19), we now have FLiRT. It sounds almost glib after what the world has been through. Are we taking the virus as seriously as we should? Associate Professor Paul Griffin says the virus doesn’t inspire fear like it used to after it was first detected on 25 January 2020.

“I think it’s clear that this far down the track from when this virus was first discovered…people’s perceptions have changed significantly, and it is much less feared.”

But he doesn’t believe there’s any link between this change in perception of the virus and its playful name.

“FLiRT is an abbreviation for the mutations in the spike protein that have given rise to the new subvariants that we are seeing cause an increase in COVID activity at the moment. More specifically it refers to amino acid changes in the spike protein, phenylalanine (F) to leucine (L), and arginine (R) to threonine (T),” Associate Professor Griffin said.

“This is not a new way of describing these changes but conveniently spells an easily recognisable word that has caught on.”

“We at times named variants after where they were originally found (eg, the UK variant otherwise known as alpha), we then transitioned to predominantly naming variants letters of the Greek alphabet and now we mostly talk about subvariants of Omicron, of which there are now well over 60,” he said.

“The subvariants are actually descendants of JN.1, sometimes referred to JN.1.* and including KP.1.1, KP.2, KP.3 and KW.1.1.”

Although it’s a unique name for a variant, its characteristics aren’t necessarily that unusual. However, it does have implications for vaccinations.

“What we are seeing is what has happened many times over, in that basically the virus has changed again, hence immunity derived from vaccination or past infection no longer provides as potent protection,” Associate Professor Griffin said.

Current vaccines that Australians have access to are not necessarily keeping up with new variants like FLiRT.

“The virus is currently changing faster than our vaccines are able to be updated. The WHO recommended updating vaccines to targeting JN.1 at the end of April but unfortunately these are not yet available,” Associate Professor Griffin said.

But that doesn’t mean people should not keep up with the available vaccines.

“My advice is for everyone to be up to date with vaccines according to their current eligibility, particularly given the rapid rise in cases and therefore risk in our country at the moment.”

While the FLiRT subvariants are not likely to be more dangerous than their predecessors, they could spread more easily.

“It is always challenging early after the detection of new subvariants to completely understand its properties. However, there is nothing at this stage to indicate the FliRT subvariants are any more dangerous.”

“When the virus changes, this can theoretically lead to a number of concerning properties including immune evasion but also potentially reduced performance of tests or antivirals although we haven’t really seen this yet,” Associate Professor Griffin said.

The reduced fear around the virus leads to a lack of testing, including of wastewater, making it harder to capture data on the virus and to see the bigger picture.

“Very unfortunately it is getting harder to understand what is happening with COVID-19 given reductions in surveillance and testing,” Associate Professor Griffin said.

“Reductions in people testing certainly means we have a reduced understanding of what is happening in terms of numbers of cases as well as what subvariants are causing them.”

“In Australia, many states have wound back wastewater testing, which is a really useful way to get a snapshot of both activity as well as what subvariants are circulating,” he said.

The lack of more severe variants of the disease shouldn’t lead people to think the battle with COVID-19 is over.

“The changes we see in the virus and the infection it causes are random so it is possible, although less likely for a few reasons, that one day a new subvariant may cause more severe disease. This is part of the reason why we can’t get complacent in terms of COVID-19.”

Concerns about bird flu

Australia’s first human case of avian influenza was reported this month, sparking huge culls of chickens on farms in Victoria where the outbreak began. Globally, the United States and Europe are looking at acquiring or making H5N1 bird flu vaccines.

Associate Professor Griffin finds the Highly Pathogenic Avian Influenza A (H5N1) (specifically Clade 2.3.4.4b) a little concerning but fortunately it is not currently being spread from person to person.

“Bird flu in itself isn’t new or concerning with avian influenza detected in poultry in Australia on nine previous occasions dating back to 1976,” Associate Professor Griffin said.

“Some of the concerning features of the current situation include how widespread the transmission is in birds and now the number of mammalian species involved.”

“While human cases have been reported, including a young, returned traveller in Australia, fortunately at this stage it does not seem able to be transmitted readily [from] person to person and the vast majority of cases have arisen via close contact with birds or infected mammalian species, particularly cows.”