It’s time to stop worrying so much about new variants

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You’ve probably by now heard about the latest variant, XBB.1.5, emerging from the viral soup of Omicron-children to menace society. Ryan Gregory, the Canadian evolutionary biologist who has become something of an unofficial namer-of-variants, calls it Kraken, and it slides into his mythological menagerie alongside Basilisk (BA.2.3.20) and Argus (BJ.1).

Professor Robert Booy, leading COVID-19 expert and friend of Examine, told my colleague, Melissa Cunningham, he’s calling XBB.1.5 “the extra bad boy”. “It is spreading like crazy in the US”.

The kraken COVID variant is dominating infections in the US but has only been found in limited numbers in Australia. Kraken is the name of a legendary sea monster off the coast of Norway as well as the new variant.

But… after several years of covering variants, Kraken leaves me cold. I’ve written a lot of stories about scary new variants only to see them go nowhere. Or they come to dominate globally but – unlike Alpha, Delta and Omicron – don’t really seem to change the pandemic in any meaningful way.

It left me wondering whether it might be time, finally, to stop reporting on every new variant that shows up. To my surprise, some (but not all) of Australia’s virologists strongly believe we should do exactly that.

“I am in strong agreement that there is little to no public health value in continuing to report the latest Omicron scariant,” says Dr Adam Wheatley, who heads a research team studying the immune response to COVID-19 at the University of Melbourne.

Business as usual

As viruses replicate in our cells, their genetic-copying machinery makes small errors. Some of these errors, or mutations, will change the virus in important ways, perhaps by modifying the protein it uses to hook onto our cells, or altering the virus’s shape in a way that makes it harder for antibodies to stick on.

When COVID-19 jumped from animals to humans, it encountered an essentially defenceless host. Our immune systems had never seen it before and had no library of antibodies to call on. That meant the virus was essentially under no pressure to get better. It just needed to find new hosts. The first globally dominant variants – such as D614G and Alpha – got there simply because their mutations allowed them to spread more quickly.

Three years into the pandemic and we’re in a very different position. By the end of 2021, almost half the global population had been infected at least once. Almost 70 per cent of the world’s population has now received at least one dose of a vaccine.

This puts the virus under new pressure. A mutation that allows a virus to better evade antibodies, infect a human cell and replicate will help it dominate its cousins. As we get reinfected with variants, our antibody arsenal expands, meaning the next-successful-variant has to be even more immune-evasive to survive and thrive.

“Each new variant or subvariant must be more transmissible than its predecessor, or it would die out,” STAT’s Helen Branswell writes.

If you think about the variant story from an evolutionary perspective, what we’re really seeing is a parade of new variants, each more immune-evasive than the last. Kraken won’t be the last Kraken, as it were.

When does it matter?

Viral evolution is scientifically interesting. The question for journalists and the general public is: when do mutations in the virus actually matter enough for us to report on them?

“The colloquial naming of these variants, like Kraken, is creating a misconception” about how important they are, says University of Queensland virologist Dr Kirsty Short.

At the moment, a lot of focus is given to how antibody-evasive a new variant is in lab testing. But we have a very poor handle on how antibody-evasion in a lab actually translates in the real world, says Short.

Instead, we need to look at severity, she and other virologists told me. Is there any evidence, from hospitalisation data, the new variant causes more-severe disease? There’s no evidence yet that Kraken fits this bill.

“We don’t cover new flu variants every time they arise – although they do every year. It is not clear why we need to cover each new COVID-19 variant unless there were evidence they are more severe,” another leading virologist tells me on background.

Small shifts in a virus’s mutation profile are called “antigenic drift”. Big jumps, such as the emergence of Omicron, are called “antigenic shifts” and are definitely worth covering.

But we’re yet to see such a shift with any of Omicron’s children, says the Kirby Institute’s Dr Deborah Cromer. Many of the variants only differ by a single amino acid.

“There have been incremental changes that avoid some existing immunity, but not fundamental changes to the virus,” she says.

Lastly, we must be careful when looking at dominant variants. Unlike early in the pandemic, each country now has a very different immunological profile – different vaccines, different infections, different dominant variants. A variant becoming dominant in one country is no longer a sign it will come to global dominance, says Dr Norelle Sherry, a variant researcher at the Doherty Institute.

I often report on things that are interesting but ultimately probably don’t matter terribly much.

But focusing on new variants may have two important effects, I suspect. By giving the variant narrative power, it diminishes our role in the story. We can change the course of the pandemic – we are simply choosing not to.

Second, it leads to practices such as testing travellers from China at the border. “The reporting feeds into the semi-racist arbitrary governmental actions that have plagued the pandemic response,” says Wheatley.

Where does this leave us? I suspect I may cool my reporting on new variants somewhat – at least until we see real-world signs of a step-change in the virus.

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