A non-spike nucleocapsid R204P mutation in SARS-CoV-2 Omicron XEC enhances inflammation and pathogenicity.

ABSTRACT: The global circulation of SARS-CoV-2 in human populations has driven the emergence of Omicron subvariants, which have become highly diversified through recombination. In late 2024, SARS-CoV-2 Omicron XEC variant emerged from the recombination of two JN.1 progeny, KS.1.1 and KP.3.3, and became predominant worldwide. Here, we investigate virological features of the XEC variant. Epidemic dynamics modeling suggests that spike substitutions in XEC mainly contribute to its increased viral fitness. Additionally, four licensed antivirals are effective against XEC. Although the fusogenicity of XEC spike is comparable to that of the JN.1 spike, the intrinsic pathogenicity of XEC in male hamsters is significantly higher than that of JN.1. Notably, we find that the nucleocapsid R204P mutation of XEC e

SUBMITTER: Tsujino S 

PROVIDER: S-EPMC12819382 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature