Britain’s Covid vaccination drive should immediately open to all people over 50, experts said, amid growing concern about Arcturus.
The new variant – which is believed to be the most contagious to have emerged since the pandemic – already makes up about 1 in 40 reported cases in the UK.
Its explosion on the scene sparked fears it could lead to a new wave, mirroring chaotic scenes in India, where mask mandates have already been reinstated in order to curb a resurgence of the virus.
Over 75s are the only age group currently eligible for another Covid jab as part of the government’s latest fortification programme.
However, one will also be offered to all care home residents and anyone aged 12 or over who is deemed to be at risk because of their health conditions.
Monitoring data shows that the strain, which is scientifically called XBB.1.16, makes up roughly 2.3 percent of all new cases. Separate unofficial figures suggest around 65,000 Britons are infected every day

A separate Covid surveillance project, run by health tech company ZOE, found that Covid rates have fallen since the end of March
Professor Lawrence Young, a virologist at the University of Warwick, told MailOnline that eligibility should be expanded.
He said: ‘We must offer at least booster punches to all people over 50 to ensure levels of protection against Arcturus, and any other variants that emerge, are maintained over the coming months.
Covid is not over with us yet and it will continue to change.
“We need to remain vigilant.”
Professor Young, who was critical of the government’s approach during the easing of anti-Covid measures this time last year, added: ‘The concern is that with lower levels of surveillance in the UK, declining immunity from previous infections and vaccinations, poor uptake of the spring booster, and the general level of complacency We are not well equipped to deal with another wave of infections.
‘Covid has not gone away,’ said Professor Anna Whitaker, an expert in vaccines and behavioral medicine from the University of Stirling.
“I would like to see it (another booster shot) offered at a younger age like 50 if at all possible, since many people in their 50s have significant comorbidities. ”
The latest vaccine was launched in Britain three weeks ago.
But, unlike other drives, there wasn’t much fanfare surrounding the project, with those eligible being contacted directly to book an appointment.
Health chiefs have repeated their pleas to urge vulnerable people to come forward for a jab, but as people were mainly targeted via the NHS app in this release, there was not the same general level of public messaging.

UKHSA officials have warned that India now accounts for 61 per cent of all recorded cases of XBB.1.16. The predominant form in the country was that, between March 20 and April 3, more than two-thirds (68 percent) of all registered cases were of the Arcturus strain. Separate figures from the Our World in Data platform run by the University of Oxford show the number of new daily cases reached 9,526 six days earlier on April 18, up from 625 recorded one month earlier.

While the rapid rise in Covid cases is of some concern, it still falls far short of the devastating wave the country experienced in 2021 from the delta variant.

Other sub-variants of Omicron include Kraken (XBB.1.5) and Orthrus (CH.1.1). For now, Kraken remains the dominant strain in the UK, as of April 14, causing 44 per cent of cases, while Omicron accounts for 8 per cent and Arcturus, 2.3 per cent, according to the UKHSA.
Last year’s spring scheme also delivered punches just for the over-75s, but another booster shot came in the fall that also included the over-50s.
It comes as MailOnline revealed today that five Britons have already died after contracting Arcturus.
UK Health Security Agency (UKHSA) chiefs detected 135 symptomatic cases of Omicron, which first arrived in Britain in mid-February.
Only one area, the Northeast, you haven’t seen yet.
But the death toll – based on genetic monitoring – will be a much lower number because only a small fraction of the samples are now being rigorously tested.
Monitoring data shows that the strain, which is scientifically called XBB.1.16, makes up roughly 2.3 percent of all new cases.
Separate unofficial figures suggest around 65,000 Britons are infected every day.
Leading experts insist there is no evidence stress is more severe than other prevalent strains.
At present, the disease caused by the coronavirus is very similar to the flu, unlike the early days of the pandemic.
warned Dr Simon Clarke, an infectious disease expert at the University of Reading This concern about Arcturus is premature.
He said: ‘While we know (Arcturus) has caused a small number of deaths, we don’t know the circumstances surrounding these cases and it may be too early to respond.
The coming months and years will bring continuous waves of new Covid variants.
“But a panicked reaction to each one can lead to public indifference to something that might really require a coordinated response.”
The previous Kraken (XBB.1.5) Omicron wave in the UK could explain why there has not been a similar explosion in Britain, said Prof François Palloux, a voiceover throughout the pandemic, from University College London.
“In places where it hasn’t had an XBB.1.5 wave (like India or China), it’s expected to do well,” he said.
“On the contrary, in places like the UK, it is not expected to have a significant impact on case numbers, and even less so, on hospitalizations and deaths.”
He added: “XBB.1.16 is still at low frequency here in the UK, but it could become the next dominant variant in the future.”
Arcturus, technically known as XBB.1.16 but given its name by variable Covid trackers, has already swept places like India causing a 90-fold increase in cases and seeing mask mandates imposed in the hardest-hit regions.