>SARS-CoV-2 is a protean virus. It seems designed to reinfect a previously infected host, changing its outer coat as well as some of its properties.
>We all remember Omicron and how it swept the world that had already experienced several waves of Covid cases. There were so many changes in the outer spike protein of Omicron that previous infections did little to protect from new infections. How much previous infection protects from disease still remains in question.
>BA.2… contained 54 amino acid mutations from the original Wuhan virus. The cause for concern with BA.2.86 is that it contains 41 amino acid mutations on top of the BA.2 mutations, totaling 95 mutations from the Wuhan virus.
>BA.2.86 is likely a common descendant of one of the original Omicron variants, BA.2, [?and a more recent variant, XBB?]. In the spike protein of BA.2.86, we see 60 amino acid mutations, including substitutions and deletions. For context, the Alpha variant, which fueled the second-largest surge of cases in the United States behind the initial Omicron surge, contained just ten spike amino acid mutations. Dr. Eric Topol describes BA.2.86 as "Omicron Squared."
>…the updated Covid vaccine set to be released this fall is designed to protect against the XBB.1.5 variant, but not BA.2.86. The hope is that the vaccine will protect against BA.2.86 should it widely circulate, but it would be unsurprising if the variant evaded booster protection, given the degree to which BA.2.86 is mutated in the spike is extreme.
