New Omicron subvariant XBB.1.5 is evaluated to account for 40.5 percent of Covid-19 cases in the United States.
The new Omicron subvariant XBB.1.5 hit in the week ending December 31, nearly doubling from the previous week, according to data updated Friday by the US Centers for Disease Control and Prevention (CDC).
XBB.1.5 made up 21.7 percent of the total cases in the previous week ending December 24. Recombinants of the BA.2 variant, XBB, and XBB.1.5 together accounted for 44.1 percent of the total cases in the country in the week ending December 31, CDC data showed.
The XBB variant has been moving up in cases in parts of Asia, drawing concerns for its high infectiousness. Another two Omicron subvariants BQ.1 and BQ.1.1 accounted for about 45 percent of new Covid-19 cases in the United States in the latest week, CDC data showed.
The report says the Covid omicron XBB.1.5 variant is highly immune evasive and appears to be more effective when it comes to binding with cells, compared to other sub-variants.
Researchers and scientists fear that the Covid-19 vaccines and the omicron boosters could be rendered ineffective due to the XBB.1.5 variant.
It also has the ability to cause even more breakthrough infections.
All US states where XBB.1.5 is dominant are witnessing a surge in hospitalizations leading to the reason that this variant is behind the increased rate of hospitalizations. In the UK too, XBB.1.5 is spreading quickly.
Scientists across the world have been monitoring the XBB subvariant family for months since the strain has many mutations.