The World Health Organization (WHO) has raised concerns over a new sub-variant of the Omicron Covid-19 strain, named XBB.1.16, nicknamed Arcturus, which has been found in 22 countries, including Singapore, Australia, the UK, and the US.
The variant has been named as Arcturus after the brightest star in the northern celestial hemisphere. It is closely related to XBB.1.5 but has two gene changes, including one in its spike protein. The WHO has elevated the variant to the status of “variant of interest” and is monitoring its spread.
Although the Arcturus strain seems to be spreading faster than previous variants and is outcompeting XBB.1.5 in many regions, it is not causing more severe illness. The WHO has stated that the risk from this variant is low, but health experts are concerned that it is showing signs of immune evasion and infecting people who were previously infected with Covid-19 or vaccinated teenagers and adults.
Last week in the United States, XBB.1.16 accounted for an estimated 10% of Covid-19 cases nationally, up from about 6% the week prior. The XBB.1.5 variant continues to be the dominant cause of new infections in the United States, according to data from the US Centers for Disease Control and Prevention.
India is currently witnessing a sharp rise in Covid-19 cases attributed to the spread of the Arcturus variant. The country recorded 10,093 new coronavirus infections in a single day, with the number of active cases increasing to 57,542. The variant is also reported to be causing conjunctivitis or pink eye, especially in children below 12 years.
The WHO is recommending that countries share information about this variant and conduct tests to see how well the immunity in their populations will defend against it. It is also asking countries to keep an eye on certain indicators of disease severity as this sublineage spreads.
