Covid-19: Omicron variant XEC ‘rising steadily’ in NZ as scientists watch for early signs of Christmas wave

Early summer bumps in Covid-19 activity – along with mid-year waves – have been an unwelcome pattern since Omicron began widely spreading in early 2022.

• Early summer bumps in Covid-19 activity have been an unwelcome pattern since the Omicron variant began widely spreading in early 2022.
• While monitoring indicates no clear signal that another Christmas wave is building, newly arrived variant XEC has been steadily gaining traction
• Health officials are encouraging Kiwis to get boosted when they become eligible if they want to avoid the worst effects of Covid-19.

A highly transmissible new coronavirus variant is “rising steadily” among sampled cases in New Zealand - but there’s no firm sign yet that the country is headed for another Christmastime wave.

Early summer bumps in Covid-19 – along with mid-year waves – have been an unwelcome pattern since Omicron began widely spreading in early 2022.

Each has come with peaks in hospitalisation numbers just days before Christmas, although the holiday-time surges have been growing smaller over time.

Covid-19 modeller Professor Michael Plank said cases had been “very slowly” creeping up, with 1411 reported around the country last week, along with 76 people in hospital with the virus.

That was likely down to waning immunity to the virus: it’s been nearly six months since the last peak in cases.

“But indicators remain at historically low levels,” Plank added.

“Hospital occupancy is lower now than at any point in 2023 so I wouldn’t say we are currently in any significant wave.

“I think we can put this down to the lack of any fast-growing variant so far this spring.”

XEC - the latest in a succession of Omicron offshoots packing new immunity-evading advantages – was confirmed here last month and was now on track to become the next dominant variant, he said.

“But it is more of a tortoise than a hare so any wave it does cause will hopefully be smaller than last summer’s wave.”

ESR’s genomics and bioinformatics science leader Dr David Winter said XEC accounted for just under a quarter of cases reported in the past two weeks and was “rising steadily”.

“While XEC has been rising, quite a few novel variants are emerging overseas,” he said.

“Most of these variants are now present in New Zealand at low levels, and it’s quite possible one of them will out-compete XEC over the summer.”

The next Covid-19 booster – targeting XEC’s parent strain JN.1, which fuelled New Zealand’s last summer wave – wasn’t expected to be available until early next year.

But health officials are encouraging Kiwis to get boosted when they become eligible, if they wish to avoid the worst effects of Covid-19.

“Immunity does wane over time and the best way to top your immunity up is to get a vaccine,” Plank said.

“This is particularly important for over-65s and other high-risk groups, but everyone over 30 is eligible for a vaccine if it has been more than six months [since] your last dose or last infection.”

Vaccines made the single largest difference in preventing death with the virus, which claimed around 2,800 Kiwi lives in 2022 and about 1000 last year.

“On current trends, we are tracking towards about 700 in 2024.”

Jamie Morton is a specialist in science and environmental reporting. He joined the Herald in 2011 and writes about everything from conservation and climate change to natural hazards and new technology.

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