The subvariant of omicron, named XBB.1.5, has raised concerns about another potential wave of Covid cases following the busy holiday travel season.
The CDC projected Friday that about 40% of confirmed U.S. Covid cases are caused by the XBB.1.5 strain, up from 20% a week ago.
There’s no indication it causes more severe illness than any other omicron virus, Dr. Barbara Mahon, director of CDC’s Coronavirus and Other Respiratory Viruses Division, told NBC News.
The XBB.1.5 is a relative of the omicron XBB variant, which is a recombinant of the omicron BA.2.10.1 and BA.2.75 subvariants.
Yet, only 37.5% of that age group has received the most recent omicron booster, according to the most recent CDC data.