“The updated Covid-19 shots are formulated to prevent severe disease and hospitalization by the XBB1.5 strain, as well as other XBB subvariants, which make up more than 90 percent of the subvariants circulating as of Sept. 2, according to the CDC. This includes EG.5 and FL.1.5.1, which make up more than 30 percent of current cases.
CDC officials said in today’s meeting that lab data also suggest that the updated vaccine will generate neutralizing antibodies against BA.2.86, which has garnered attention due to its high number of mutations. It has only been found in 10 countries worldwide, and seven states within the U.S, but it is not clear that it will gain additional traction.”
https://www.politico.com/news/2023/09/12/covid-flu-rsv-shots-00115388