Neutralisation sensitivity of the SARS-CoV-2 XBB.1 lineage

Co-infection with multiple SARS-CoV-2 lineages can result in recombination of the viral genomes and the emergence of novel, recombinant SARS-CoV-2 lineages.1–4 In January, 2022, the recombinant SARS-CoV-2 XBB lineage was first detected in India and incidence is increasing in Asia and Europe.5 The XBB lineage is the result of recombination of two omicron variant sublineages, BJ.1 and BM.1.1.1, and the breakpoint is located in the gene for the spike protein (appendix p 10),6 which is responsible for host cell entry and constitutes the target of neutralising antibodies.