XBB.1.9.2.5.1), are the predominant variants circulating worldwide.1 Unexpectedly,
however, a lineage distinct from XBB was identified and named BA.2.86 on Aug 14, 2023.2
Notably, BA.2.86 bears more than 30 mutations in the spike (S) protein when compared
with XBB and the parental BA.2, and many of these mutations are assumed to be associated
with immune evasion (appendix p 10).2 Although the number of reported cases is low
(68 sequences have been reported as of Sept 7, 2023), BA.2.86 has been detected in
several continents (Europe, North America, and Africa), suggesting that this variant
might be spreading silently worldwide.