Fears new ‘Arcturus’ Covid variant could become dominant in UK and spark new wave of infections

Concern is growing that a new Covid variant behind a rise in cases in India could become dominant in the UK and prompt a new wave of the virus this spring.

The new variant named “Arcturus” is behind a surge of infections in India where the latest figures show overall Covid case numbers have surpassed 10,000 infections a day and have soared 13-fold in the past month.

Virologist Dr Stephen Griffin from the University of Leeds said Arcturus is growing at a faster rate than other variants and is “rapidly outcompeting” others in India. He added that the new variant, which is now spreading globally, is particularly concerning because of limitations in genomic sequencing and tracking, leaving the UK “completely in the dark” after it stopped publishing ONS Covid case figures last month.

So far in the UK, Arcturus accounts for just 0.4 per cent of cases, according to the GISAID virus sequencing database – but that proportion is expected to increase considerably.

“Arcturus has a growth advantage of about 1.2 compared to what we’ve had recently,” Dr Griffin told The Independent. “It’s conceivable it could outcompete what we’ve had recently but there are other variants in the mix so it’s hard to know which one will become dominant.”

He added: “We’re still in a pandemic. New waves of the infection are being driven by the viral variation and we have an endless resupply of susceptible people because this virus is escaping our antibody-mediated immunity.”

“We had five waves in 2022 and this is another one.”  

Dr Griffin said it was hard to predict the impact of the new wave but with the current state of the NHS – with patient hospital pressures, backlogs and strikes – means any impact “would be bad”.

He also said cases in the UK could match those seen in India (10,000 a day) with the rise of the new variant but it would difficult to quantify that figure given the lack of testing.

Dr Vipin M. Vashishtha, a paediatrician and researcher who has been tracking Arcturus’s rise in India, said cases there were increasing “exponentially” and fears the key spike protein mutations in the new variant could make it make aggressive.

“It’s difficult to uniformly say it will cause large outbreaks globally but considering the mutations to it, this variant will lead to a higher rate of infection and may prove to be more aggressive,” Dr Vashishtha told The Independent. “In the US, it’s growing above current dominant variants so it could supersede elsewhere.”

“In India so far it’s [Arcturus] only causing mild illness. There’s not many hospitalisations and deaths but gradually they are increasing in two to three states with Punjab, in particular, seeing more admissions and people on ventilators.”

Dr Vashishtha joined calls for governments worldwide to improve genomic sequencing at airports to ensure new variants are detected early.

Virologist Professor Lawrence Young, from the University of Warwick, told The Independent that the rise of the new variant in India was a sign that “we’re not yet out of the woods”.

“We have to keep an eye on it,” Prof Young said. “When a new variant arises you have to find out if it’s more infectious, more disease-causing, is it more pathogenic? And what’s going to happen in terms of immune protection?

“These kinds of things highlight the importance of genomic surveillance but a lot of countries including our own have let our guards down a bit and we can’t be sure what variants are around and what level of infection they’re causing until we see a significant outbreak.”