This post has a little more info (and some mappings if you're into that sort of thing) on the mutations of BA.2.86
	
	
		
			
				
			
			
				
				Facts, data and analytics about biomedical matters
				
					
						
							
						
					
					erictopol.substack.com
				
 
			 
		 
	 
The impact of these striking differences will be immune escape—that is more difficult for our immune response to recognize this variant even with prior vaccinations, boosters, and infections—because it is new and different. It’s still SARS-CoV-2 so we have build some immunity, especially via our cellular T-cell system that is less sensitive to variants. But the rapid ability to neutralize the virus depends on antibodies, and the levels of those neutralizing antibodies are bound to be much lower against BA.2.86 than versions of the virus we have previously been espied to or immunized against. Also to note, the burden of new mutations for BA.2.86 is not confined to the spike and is seen broadly across other components of the virus.
The XBB.1.5 update booster would have been quite useful because it matches up pretty well to EG.5 and FL.1.5.1 (gaining in the US) with only a few mutations that differ, but it isn’t likely to be as helpful against BA.2.86. If BA.2.86 takes off, it will be a real test of how good our T-cell response can rev up to meet the challenge.
he also hammers home the long-argued point that "
Chasing Variants Doesn’t Work Well"
The strategy of picking a spike variant for the mRNA booster at one point in time and making that at scale, going through regulatory approval, and then for it to be given 3 or more months later is far from optimal, as the BA.2.86 story reinforces.