Fig. 1. Mutational profile and prevalence of the XBB.1.5 SARS-CoV-2 lineage.

A Amino acid mutations in the spike glycoprotein open reading frame for various Omicron and XBB sub-lineages. Each coloured box represents a mutation within a specific omicron sub-lineage. NTD amino terminal domain, RBD receptor binding domain. B Weekly weighted estimates of lineage proportion from sequencing data in the United States³⁹. Weeks from 28 Jan–11 Feb 2023 represent Nowcast estimates which consistently align with the weighted proportions based on reported sequencing data. C CryoEM density map of the XBB.1.5 spike protein, with each protomer coloured a shade of blue or purple. D Resultant atomic model of the XBB.1.5 spike protein with modelled mutational locations denoted with red spheres on a single protomer.