XBB.4 is a sub-strain of XBB. XBB.4 obtained a key mutation on the basis of XBB, while XBB.4.1 obtained a T470N mutation on the basis of XBB.4. Although this strain is not reported in the United States at present, it is suspected that it was introduced into the United States a few days ago according to our data.
From:Wireless / CN / Jinan
