Divergent Evolution and Local Establishment of Multidrug-Resistant <i>Shigella sonnei</i> in China.

ABSTRACT: This study explored the microevolution of Shigella sonnei in China, focusing on 281 isolates exhibiting coresistance to ceftriaxone and azithromycin (cef^Razi^R) and 99 ONPG-negative isolates. Phylogenetic analysis revealed that waterborne outbreak strains, characterized by multidrug resistance (MDR) and cef^Razi^R, clustered within the predominant domestic lineage I. In contrast, sporadic MDR strains harboring a wider array of antimicrobial resistance (AMR) genes were primarily associated with lineage II. The cef^Razi^R phenotype in lineage I was mediated by an IncB/O/K/Z plasmid carrying bla _CTX-M-14, mphA, aac(3)-IId, dfrA17, aadA5, and sul1 genes. Lineage II strains acquired

SUBMITTER: Liu K 

PROVIDER: S-EPMC12778403 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature