India's first case of the XBB.1.5 subvariant of Omicron was confirmed in Gujarat by the national genome sequencing consortium on December 31. XBB.1.5 is a recombinant, which means its genome is the product of the genomes of two different strains spliced together. This can happen when two strains infect a person at the same time. Previous recombinants include XD (Delta + Omicron), XE (BA.1 + BA.2), and XBB (BA.2.10.1 + BA.2.75). XBB.1.5 is better at binding to ACE2 receptors in the body than XBB or XBB.1. So XBB.1.5 is more transmissible giving it more opportunities to mutate to more potent forms. With the hybrid immunity in India, no sublineage is likely to cause a fresh wave.