A new Covid strain nicknamed ‘Arcturus’ is raising concern around the world.
XBB.1.16, a sub-variant of Omicron, is already wreaking havoc in parts of India.
Now it’s starting to sweep through the UK and US.
But where else has the species been spotted? Are there any new symptoms? Do vaccines still work against it? And why is it even called Arcturus?
Here MailOnline breaks down everything you need to know about the new variant.
The new Covid variant XBB.1.16 dubbed ‘Arcturus’ has led to a massive increase in cases in India over the past month
Analysts from the Office for National Statistics estimated that nearly 1.7 million Britons were carrying the virus on any given day of the week up to March 13. This is an increase of almost 14 percent compared to the previous week
What is XBB.1.16?
XBB.1.16 is a mutated version of Omicron XBB, a strain first discovered in India in August.
The parent strain XBB – a fusion of BA.2.10.1 and BA.2.75 – caused the number of cases to quadruple in just one month in some countries.
According to the World Health Organization (WHO), it is one of more than 600 Omicron sub-variants currently in circulation.
Other sub-variants include Kraken (XBB.1.5) and Orthrus (CH.1.1).
The latest data from the UK Health Security Agency shows that Kraken was the dominant strain in the UK on March 26, causing 51 percent of cases.
Orthrus trailed with 10.4 percent.
Why is it called Arcturus?
Like similar new Covid variants, virus trackers online decided to name XBB.1.16 ‘Arcturus’ following a pattern of naming new strains after mythological entities.
It means ‘guardian of the bear’ and is related to the Ursa Major constellation.
Arcturus is also a red giant star and one of the brightest stars in the Northern Hemisphere.
Located nearly 37 light-years away, it is visible from Earth.
Why has it caused concern?
The WHO is currently monitoring the Arcturus strain, with officials saying there are some concerning mutations.
At a press conference on March 29, Dr Maria Van Kerkhove, WHO’s Covid technical lead, said: ‘We have not seen a change in severity in individuals or in populations, but that is why we have put these systems in place.
She added: ‘It has an additional mutation in the spike protein that has shown both increased infectivity and possibly increased pathogenicity in laboratory studies.’
The variant has led to an increase in cases in India, with infections rising 13-fold in the past month, sparking concern among officials.
This has prompted the country’s health authorities to conduct hospital exercises and reintroduce mask mandates in some areas.
A study by Japanese scientists has also suggested that Arcturus is 1.2 times more contagious than the closely related Kraken Covid strain.
They uploaded their findings to the bioRxiv biological research website, writing that this benefit suggests the new variant will “spread globally in the near future.”
How deadly are the symptoms?
While the WHO has confirmed that ‘Arcturus’ has mutations on its spike protein that could allow it to increase its ability to infect humans, there is currently no evidence to suggest that it increases the severity of the disease.
Although it is believed to be the most contagious variant to date, it does not appear to be more deadly than other Covid strains.
But a rise in cases could put pressure on health services.
Typical symptoms of Covid include high fever, cough, cold and loss of taste or smell.
But frontline doctors in India claim to have seen an increase in infected children battling conjunctivitis, suggesting it causes slightly different symptoms than other variants.
Vipin Vashishtha, a pediatrician consultant at Mangla Hospital and Research Center and a former civil servant at the Indian Academy of Pediatrics, revealed that symptoms affecting children’s eyes have seen a sudden rise.
He said he is now seeing a rise in cases of ‘itchy’ conjunctivitis or ‘sticky eyes’, a symptom he had not seen during previous Covid waves.
Vipin Vashishtha, pediatrician consultant at Mangla Hospital and Research Center and former president of the Indian Academy of Pediatrics revealed that symptoms affecting children’s eyes have seen a sudden rise
Where has it been spotted?
According to WHO officials, XBB.1.16 was first discovered in late January, with Dr. Kerkhove confirmed that ‘it has been in circulation for a few months now’.
It has been monitored by WHO since March 22.
According to the latest data, the variant has since been reported in 22 countries, but by far the largest outbreak has been in India.
India’s health ministry reported 10,158 new cases of Covid today alone, almost double the number (5,335) reported a week ago on April 6.
Maharashtra and Delhi also reported more than 1,000 daily cases yesterday, for the first time this year.
These Covid cases could be those who test positive while feeling unwell at home as well as those who are in hospital.
Data also suggests that “Arcturus” has already reached more than half of all US states.
Health chiefs first discovered ‘Arcturus’ in New York in late January.
But it has since spread to 26 other states and caused 235 cases, with hot spots in California, New Jersey and Virginia.
MailOnline also revealed yesterday that the variant is already in Britain.
How many UK cases are there?
The UK Health and Security Agency said the variant was already in the UK in its latest variant report released last month.
Separate data collected from variant trackers reports that the UK has now sequenced nearly 50 samples from Arcturus.
But Professor Paul Hunter, an infectious disease expert at the University of East Anglia, told MailOnline: ‘I suspect we will see a wave of infections with this variant.
He said: ‘I doubt it will create a big wave, probably not even as big as the one we just had in the UK.’
He added that as a result it is ‘probably’ not going to put much additional pressure on the ailing NHS, which has struggled during the pandemic.
Do the vaccines still work?
Early results suggest that ‘Arcturus’ has no greater ability to evade vaccine protections compared to other Omicron spin-offs.
Even if the vaccines don’t work perfectly against the variant, immunity is likely to hold, as most Britons have also been exposed to former Omicron variants.
A high level of protection against the virus last year gave ministers the confidence to scrap all Covid measures as the country started living with the virus.