XBB.1.5 mRNA COVID-19 vaccine protection against inpatient or emergency department visits among adults infected with SARS-CoV-2 JN.1 and XBB-lineage variants.

As part of a multi-state viral genomic surveillance program, we conducted a case-only analysis to evaluate the effectiveness of XBB.1.5-adapated mRNA vaccines in preventing severe illness among individuals with medically attended SARS-CoV-2 infection.